Everything I've learned about suspension in the past 5 years
 

This may be a fun thread. It appears there is a fair amount of interest in suspension tuning. I recall the days when I had no freakin' idea and was scared as hell to touch any suspension parts on my car for fear of lord knows what.

The purpose of this thread is to share the path that I took. Lots of turns, twists, reverses of logic, beliefs that I thought were breakthroughs only to get overturned later and thought stupid.

Here goes:

I owned (man this is feeling like a long post already---better plug in the laptop power cord) a 2005 Mustang. Bought it because it looked cool as crap. Some of you might remember the 2005 Daytona Grand-Am race where a white 2005 Mustang won. Man that car looked sexy. Big Hoosiers. This is the picture that did it for me---the white car:

http://cache.jalopnik.com/cars/asset...Man-Racing.jpg

So I bought a slightly used 2005 white Mustang with 26K miles and began looking for aftermarket go fast goodies. I found a giant goose egg as the car was too new to have any parts developed for it.

Drove the car in several NASA HPDE events. Drove it to the track. Wore off the front outside edge of the left tire. Did it again. And again. Had 19" wheels because they looked cool wrapped with directional tires and freakn' cool wheels. Car looked pretty--pretty stupid as the cost of these 19" was stupid expensive. After spinning the car out several times and hitting some tire walls, my HPDE3 reputation began---"Meyer is a wild man". I pushed the edge and often found it. Can you say bodyshop? I continued progressing and went to every NASA event in the Midwest and Ohio/Indiana regions for two years. I think I missed two NASA events in these regions over two years. Road tripped out of region to NASA VIR, NASA Road Atl and a few non-NASA events. Seat time, seat time, seat time. During this progression I came across a guy here in Indy named Kenny Brown. Kenny Brown has a road racing experience with several racing teams and had a nice little business making and marketing road suspension parts for Mustangs. He is right here in Indy. We befriended each other and before I knew it he was pathing me to a suspension education.

He was/is a big supporter of tire temperatures. This was the primary logic he used to show Ford Mustang owners that thier cars needed front camber. The majority of Fords have a rear "live" or "stick" or "solid" axle as opposed to our rear RX8 Independant suspension (IRS). His products and approach is different than our IRS cars because they had to work on these solid rear axle cars. Camber and toe adjustments were small and near impossible to obtain (let's not talk about this now please). He advised me to purchase a tire pyrometer and I did. A good tire pressure gauge, seat time, and the recording of lots of tire data followed. I showed him my written down data: track temp, tire temps, tire pressures, time of day, wet/dry/overcast/foggy/tornado (yes we had a tornado at Autobahn in 2006 I think it was). When I got back from a track event evaluated and SLOWLY made changes. I didn't know what he was doing and later found out he was adding a smidge more camber. SLOWWWWLY he would add just a bit more camber.

So I'm starting to hoof this bad ass car http://ericmeyer.smugmug.com/Meyer-M...33719387_nhBSd

and Kenny is making some adjustments every couple of weeks. I strip the cars interior, add a Sparco seat, a roll bar (not a cage) a steering wheel and man do I feel like one bad ass mofo. Kenny does some black magic computer stuff and tells me something about "roll center". He makes some crazy gismo part that attaches to the rear differential, adds some front toe-out and we go back to the track. Car feels better and goes faster. We add the normal cold air kit and some mufflers followed by expensive ass wheels and front stoptech brakes. The day the car got brand new wheels wrapped with Hoosiers and the Stoptechs was better than a new bike at Xmas. Man did that car look cool. At the time I was into what the car looked like so I know where a lot of you guys are coming from on this forum. WRT modiying cars--been there, done that, own a whole mess of t-shirts to prove it. Spent a lot of money. So the car has advanced faster than my driving skills (oh yeah---we made the first coilover ajustable Koni shocks for this car) so we could play around with spring rates. Kenny made a front strut tower brace and a front swaybar I recall. He added stiffening frames on the bottom of the car. So my car is advancing faster then I and I find myself spinning out in the rain down the front straight at Mid-O and reinforcing my career as the wild man named Eric Meyer. A few more spins into tire walls and off track excursions lead to conversations with the safety officials and hand slaps. I learned a lot too.

24 hours of Daytona. A good friend of mine that I came up through HPDE with, Dan Fargo, suggested we go to the 24. The year was 2006. We did the Grass Roots Motorsports package (highly recommend) and man did I really hooked. Daytona in January is a nice break from the Midwest cold. Cheap flights into Orlando. Rent a car with a coupon. Stay on the beach for $70/night double occupancy. At Daytona I decided that my next step in the NASA path was Time Trails (TT). At this point it is VERY important to point out that these early NASA days had what I now know as a totally dysfunctional and undocumented Instructional process. Dan and I would talk a ton about "what the hell do we do next/what are we suppose to learn/what do we do to get into HPDE 4, etc. Dan drove a marine blue 1.6L Miata and towed a small trailer to the track. I bought a 8 million pound steel open trailer and trailered my Mustang with him. We drank like rock stars at night, chased each other down on the track---he caught me in the corners, I left him in the straights. We had a blast. We struggled with instruction and mentored ourselves. Looking back we realized that we had shit ass instruction, were allowed to advance to HPDE3 and 4 and had really crappy (if any) sound driving foundation to fall back on. This was a blessing in disguise. Advice: get the best instruction you can afford before going out on your own. I suspect the old NASA OH/IN/Midwest instruction (now totally different as Dan is now the lead instructor for the NASA Great Lakes region) kept us from advancing more quickly.

So at Daytona I made the decision to transform the Mustang to a TT car, continued in NASA and stupidly added a big h.p. supercharger in the fall. Road America with a supercharger on worn out Hoosiers in October. I think it was on a warm up lap and over 100 mph into canada corner and we buried that damn car deep in the gravel trap. I swear we were so far in the sand you could see the freakin' ocean. Laughed my ass off. That day I really learned the value of a warm up lap and how tires take much longer to warm up on longgggg fast tracks. Especially those that are shaded from sunlight. A lesson I never forget. Supercharger was wicked. Top Speed was what we bragged about. At the time I took it for granted that I knew the line, was driving the maximum speed anyone could take my car through a corner and thought seeking out instruction was a sign of weakness. Sound familiar anyone? Been there, done that, got a closet full of t-shirts.

Let's fast forward. Take the car to a fuc___n crook in St. Louis. The plan was to make a wicked American Iron Extreme car with 500 hp using my Mustang shell. Paid about 122 thou for a car that he still has cause he F---ED me. Buyer beware. That's a $122,000 lesson and I have no car. Expensive lesson. Anyone that can beat that story I will purchase one fine steak dinner if you come to Indy.

I have this crazy 600 hp+ E55 Mercedes. Dyno sheet attached: http://ericmeyer.smugmug.com/Rides-a...167_XhaYa-A-LB

My competition racing license was acquired in this $100k car. In the rain at blackhawk farms on Easter Sunday 2006. Me and a hodgepode of race cars running 3 wide in the rain. It was the most awesome thing to date at the time. Guys---you think driving is fun? Just wait to you get to comp school. You have no idea. Words can not express how cool this is. Some of you know this 1st person. Some of you think you know it---you don't.

So this father and son team from St. Charles Miss. has the Mustang. They tell me it will be ready next week, then next week, then next month, then no return phone calls. It's Spring 2006 and I have no car to run at Putnam Park. I rent a Spec Miata for $1,600 a weekend and prepare to whoop ass on all these sissy boys driving a girls car. I get next to last place. WTF? I tell the car rental guy that the car is a dud. He throws done the 2nd or 3rd fastest time of the day and proves me wrong. Big lesson here sports fans: When you think you're a fast driver have somebody drive your car and humiliate you. A real man will do this. A p__sy will fear this. Make sure you pick the right person. I will be happy to do this with your car if the opportunity exists. Keep in mind that I'll go over your car tooth and nail before I get in. There are many people out there that mechanically mean well and you'll always come across a "whoops, I forgot" with a loose bolt, lugnut, incorrect tire pressure, ultra-thin used up brake pads because that driver (once me/go the t-shrit) was extending every last bit life from my brake pads---whoops----new track that is really hard on the brakes and I, I, I......didn't bring another set (been there, done that....). Sometimes a certified mechanic can make a mistake. No person is perfect.

So thus began my career in the most fun and most competitive amateur road racing class money can buy. Girls cars? I'll take a great spec miata driver over 99.9% of the people on this forum. Spec Miata's are the foundation of racing sports fans. Period. Period. Did I say period? Caveat: I don't know jack about Auto-X and don't claim to. Those guys at the top of thier game have my respect. Wish I had time to learn the art of Auto-X.

So I've bought this same Miata and I'm afraid as hell to touch the suspension. Tire pressures are religously monitored and I am able to end up within 1 psi on every tire just about every session. Off track excursions continue. Wild man reputation continues. Finishing positions advance. Me and my Spec Miata homeys have more fun than you can imagine. Get my first podium (almost better than sex). Go to SCCA comp school in roebling road and get a 1st. Total a car. Build a new car. Wreck it a bunch of times. A friend of mine suggests I hire a coach. I hire him. $1,000 for a three day NASA weekend at Mid-Ohio plus expenses. Some professional racer kid about 20 years my junior. He told me to get a traqmate. I buy a traqmate. He shows me where my inconsistancies are leaving me a half a second from the right hander after Mid-Ohio's famous Madness to the the up and over right hander (Mid-O has a zillion different corner numbers so I omit these on purpose). Those of you have driven this know what I'm talking about.

That weekend was a huge revelation and I've since had a few more gigantic steps in driving philosophy. I think I took two seconds off my best time that weekend. Tom is a great friend and still my # coach. He is the best guy I know of that does this. Google him and you'll find his professional driving results. Amazing. He will drive your car faster then it has and ever will go.

Now let's get back to the suspension now that you have my life story. We're still at Mid-O and Tom is asking me "how is the car in this turn?". "How is the car in that turn". "I dunno" I reply. He has me thinking now and my brain is exploding. Being able to communicate what you're car is doing was HARD. Tom figures out that the car needs to turn to the right better. He goes under the car and spins the right rear shock collar 1 turn. This puts about .3 more cross in it. Car turns better in right turns. Wow. I'm sold. We try something with the front bar and the car goes faster. I having fun as I'm now passing guys I could never pass before. Awesome.

My fiscally responsible self buys some used longacre scales for $500, uses and learns the finer nuances of traqmate and springs for a 78 foot toter home for $307,000. Been there, done that.....

The following season I changed cross weight, I lowered the rear end when the car had too much oversteer. Later I would learn that this is called "lowering the rear roll center". I ran with the bars soft. I ran with the bars hard. I detatched the bars altogehter and had a car that had more rolls than a bakery. Toe in, toe out, zero toe. Tried everything that car could do that I could think of. Note: Spec Miata suspension has non-adjustable SPEC bilstein shocks, a fixed spring rate and eibach swaybars with some adjustment. You are not allowed alternative bars, springs or shocks--against the rules. You learn a lot when you have limited things you can do with a car. You make use of the things you have to work with. You gauge your success by your finishing position or how solid the car feels. I became more confident.

2006 was the first NASA National Championships at Mid-Ohio and my 3 homey Spec Miata drivers go 1, 2 and 3. I finish 12th or something. Engine problems. Get engine fixed and Putnam Park October I find myself running with the 1, 2 and 3rd fastest guys in the U.S. I'm first, I'm third, I'm second, off track, back on track, passed, catch em, off track. The car I'm running has full soft bars and high ride height. Car has lots of roll but I'm hoofin' like a rock star. Toyo RA1 tires are going off with two laps to go. Turn 9 out of shape. Turn 10 off track. Hit the hay bails and go inverted. Remember the seen in TopGun where Tom Cruise is talking about goin' inverted to get the look on the Mig or whatever it was? The one where IceMan calls B.S.? Dude, that was me. Dirt track to hay bails to looking directly through the windshield at the track surface about two feet from my face, car rolls back over on all 4's (no sh_t) and is still pointed down the straight. Lady's and Gentlemen spectators have just witnessed a perfect barrell roll. Broke both my wrists. Valuable lesson---know the limits of your tires.

Rebuild the car. New paint job. Thing looks wicked. April Mid-O NASA race and my buddy tags me in the right rear, the car spins counter clock at over 100 mph and scrapes the entire new paint job on the passenge side from nose to tail. Car is done. I go to medical. My crew (unknown to me) rises to the challenge. I return back to the rig and see 4 guys on the bent jalopy like ants at a picnic. They replace the entire right side suspension (another lesson---bring pleeenty of spares.). I had acquired many, many spares including wheels, controls arms, brakes, hubs, spindles. When you have spares you meet people. You make friends. You help someone out. Later on they will return the favors I've found. They will be kinder to you when on track. Someone you've never met is more likely to punt you off the track. A friend will race you more cleanly. Make friends. Introduce yourself to other RX-8 owners at track events. Make the effort. Take the initiative. They could be Auto-X champions at this first road course event or former racers that are just getting back on track after years off doing the parenting thing. You never know.

So they fix the car. All my Spec Miata friends are amazed. We go fastest in practice the following morning and I was so proud of my crew. I think we earned 2nd that day with a smashed up, dented cracked windshield heap. All this time we used the scales, check tire pressures HOT (which means coming in early in practice after a zinger lap). BTW, FORGET ABOUT GETTING THAT EXTRA LAP OF LAP TIME during your session guys. Pull in early and take temps and pressures. A cool down lap is worthless for data collection. If you ask me taking tire pressures and temps back in the paddock is a waste. Do it hot. You might think that people will think you're stupid. F them. Do it. Learn. Try stuff. Experiment. Use a test day to try things. Or......keep doing what your doing.

That car gets totaled and I end up building a new wicked '99 with the bigger motor (and heavier class weight). Earn a 7th in the nationals. Go to Barber in the fall. Fastest in practice the first time on track. Qualify first. Car totaled on lap 2 after being hit by someone who meant well. S__t happens. Be prepared to lose your car if you want to play hard.

On the drive home I thought about what my 2008 plans would be. I wanted to push myself. Call Tom Long. He suggests Mazda MX-5 cup. I think Koni. I think RX-8 because it's rear wheel drive, IRS suspension, it's in the zoom-zoom family. Find a SCCA T3 RX-8 car on the web for sale. This was the white car for those of you that have been following the team. $18,000 I think with a fresh motor, roll cage, AIM dash, 3 sets of wheels, extra trans. I'm in. Next week I'm the owner of a totalled Spec Miata and a 2004 RX-8 T3 race car.

We use the same exact philosphies we used in Spec Miata suspension tuning with the RX-8. I buy the Grand-Am Koni Spec RX-8 shocks. We go to Putnam to sort it out. Car handles weird. Hard to drive. Think, think, think. What's wrong??? I am running the SpeedSource 3 piece front bar with Alum. arms, Mazdaspeed rear swaybar, Koni shocks, Grand-Am spec Hoosiers and some crazy spring rates. I think they were 600F and 450R. Don't recall. Take the car to CMP. Tom Long is parked right next to us supporting customers with Spec Miatas. Car is handling really weird in 6 and 7. Oversteering suddenly. Car is scary in the fast T8. Spooky. Major rear inside wheel spin in T 14. Tom drives it. He's .5 faster and I'm feeling pretty good that my times are close to his. He can't figure it out either. At the end of the day we figure out that we are just barely hitting the rear bump stops which causes the car to go directly to oversteer. Lesson learned---zip ties on the bump stops and check them everytime. You generally creep up on this issue as you add grip and learn to go faster. You can just barreeely creep up on this and the symptoms can appear very inconsistant. Experiment at the track if you own aftermarket shocks. Can you confirm your not running out of shock? Take a look. Look frequently. Different tracks yield different suspension dynamics.

2005 I go to Daytona. I vow to come back in 2006 and crew. Crew for a 24 hour 2006 Rolex team--Stevenson. We start two cars and finish two cars. The stars and stripes corvettes. Vow to drive Daytona 2007.


Part two of two post continued below:

Part 2 of 2:

2007 Grand-Am Koni Daytona. Wow. Hard on the size of Texas. Rent an RX-8 from a Koni team. Bring my guys so we can learn from a pro team. Wow. High bank is killer. I'm screaming on the microphone "yeeeeeeeehaaaaahhhh!!!!!!" Total fun. Car spins out. Brakes lock up. I figure out that me and my crew know a lot more than the team I'm renting the RX8 from. My guys find issues with the car and suspension. They tell me the car is unsafe and since I trust them with my life I follow their advice. Safety is # 1. The ABS locks up at about 120 going into the bus stop. Car spins. Backs into tire wall. I'm two seconds a lap off my 17 year old co-drivers pace. Turns out the suspension is whack, sway bar disconnected, one rear wheel has huge toe out, ABS unhooked--note to self------very important. The kid is so good that he can drive a car that I think is technically totally hosed up. When the ABS is not connected in the RX-8 on any corner of this car you have a very unsafe car. This is a very unsafe situation my forum friends. I will never drive an RX8 unless I know the condition of the brakes. The car will give you a false brake pedal feel and then go to total lockup. If you can tap into the ECU you will read a wheel speed signals. A wheel speed of 203 mph indicates an ABS failure issue. It may be unplugged or the wire is cut. I would not get into an RX-8 with an ABS failure ever again.

Fly back home to Indy and decide right there in first class drinking Beam and Coke that I'm going to start a Koni team (which is a really long story)

Fast forward and a few lessons learned:

-You can't effectively setup a car when your tires are used up or heat cycled out
-Have someone faster than you drive your car, look at the data and discover why they are faster
-Nut and bolt your car. The faster you go the more pain you can cause yourself if you go off track.
-Even the best drivers crash. Safety is the best investment you can make. A proper checklist and going over your car is smart.
-Disconnect your swaybars in the rain and your car will handle better.
-Respect the high temperature of the rotary exhaust. We lost a car because of a dyno fire. Probably $130K of parts (and mostly R&D labor). We stopped Koni after that one.
-Hoosier rain tires are unlike anything you've ever driven (in the rain).
-Double your tire budget if you want to run up front.
-Some of the best driving you can do is in the rain. Most people avoid it. This is great because fewer people are on track. Dress warm and go to the event. Some people will bail out at the last minute when the forecast looks like rain----bingo! Learn to move your hands and feet as slow and gentle as possible. The RX-8 is wonderful in the rain. Remember to disconnect your swaybars!
-Scrub in your tires, brake pads and rotors and save them for a time when you need ready-to-rock pads, tires and rotors. Use a warmup session to do this. Put them away and you can use them in a pinch.
-I think I spent about $300K one year cutting my teeth in racing. Too premature. Should've stayed a year out, sorted the cars and learned how to drive them faster. The guys and cars in Koni are fast. Go karting kids are freakin' insanely fast. Hard to beat those little buggers. They are fearless.
-I think we blew 14 motors one year.
-Our ECU alternative for Grand-Am said $13K and change. It was a little more. about $50K when all was done. Take your budget, add 20%, add 20 more percent and then double it. Getting your feet wet in pro racing as a team owner is crazy expensive and we still finish mid-pack.
-Experiment with different brake pad compounds. We use Hawk. I am very confident in them. The DTC series is far superior to the old Hawk Blue's that are out there. Hawk Blue's were a marketing success and Tire Rack thinks they are still the schizzle. They are old technology. We have triend DTC70 Front and 60 rear, 60/60, 60/10, DTC 30's. We usually end up with DTC60/10. Try them. Contact my buddy Jay Andrew (and Meyer-Motorsports RX-8 co-driver). www.andrew-racing.com He has tons of brake knowledge and I'll suggest to you that specific knowledge is ALWAYS better than low price. Talk to him. He will invest time with you. He has a ton of RX-8 stuff in stock for us. Jay can be found at various NASA events and evaluates rotor temps in pit lane (and I do this with him too), studies used brake pads, helps bleed brakes and generally helps you evaluate your braking system.
-We've made a dozen different headers and have pulled over 210 chassis hp and 140+ ft lbs on over a dozen motors in a row. I think we saw 225 horse one time in 5th gear. Couldn't back it up so it doesn't count. 223 we hit several times on pump gas.
-Data collection is the ticket. A traqmate or better yet an AIM Pista display/data acq is a great investment. The AIM plugs right into your OBD2 port and accesses info in your ECU. Email me if you have about $2 grand and are considering something like this. DON'T contact me if you like to talk about stuff but don't have a budget for it. Thank you.

For the past year and a half we have tried various swaybars, spring rates, shock settings and combinations of the above. We've driven tracks with no grip, used a 225 Grand-Am Hoosier, a 245 R6, 235 Toyo 888 (yuck) and Hankooks. We've sought really tight turns, long sweeps, high speed brake zones, chicanes, rain and any conditions we could find to expose the car to different environments.

There is a great pocket handbook to purchase when you go down the aftermarket suspension road. We discovered it when we struggled with setup and couldn't figure it out. Give it to a friend for Xmas. http://www.CarrollSmith.com/books/#pocketbook

So there you have it. I've come from the same places most of you guys are at or are headed to. Try stuff. Get seat time. Get instruction. Measure things. Take notes. Talk to people that are more experienced than you and listen. You don't have to take their advice---just listen to it. Try it if it feels right to you. Think long term. What are your goals for 2010? Go from HPDE 2 to HPDE 3? Do 5 track events? Learn a new track.

There you have it. Hope you enjoyed.

Woah........that's a long and interesting journey.......
Great advice..........:ylsuper:
Definitely will tamper more with the suspension/ARB/tire pressure/alightment in 2010..............

Cheers
Alan

Awesome read Eric. thanks

Nice read Eric. Been there, Done that. Fortunately, I didn't spend the money you did. I got out about 10 yrs before you started.

Thanks for the awesome story Eric. A great read.

Eric Meyer, you are my hero.

great read and very informational

Great read. Some really helpful information in there.

awesome read.

Great read Eric, you should write one of those 'Racing faster" paperbacks. You've got a nice way of winding a tale! But this was like only the 'Forward' of said tale. So for once I'm siding with Team, this was hardly everything and esp. ... "Everything I've learned about suspension in the past 5 years" ? Hummm....

You got closer a few sentences on... "The path that I took" ... then add "getting to Myer Motorsports" perhaps?

Anyway... I came here to see what you were going to say about answering the question you said you were going to start a new thread about in the 'would 255/40/18 be grip overkill w/ a stock powered 8?'? You know, I asked how ta hell do you set up an RX-8 with a thumping front sway bar and nothing in the rear... using only rear springs and shocks??? ... and actually have it handle well? You said that's how you're running the car now, yes?

A few pics:

Bigger front bar (will measure O.D. and share later) http://gallery.me.com/meyermotorspor...&bgcolor=black

Upper front delrin: http://gallery.me.com/meyermotorspor...&bgcolor=black

Front Sway Bar quick release pins (rocket science at its finest): http://gallery.me.com/meyermotorspor...&bgcolor=black

Sexy new wheels: http://gallery.me.com/meyermotorspor...&bgcolor=black

New dry sump: http://gallery.me.com/meyermotorspor...&bgcolor=black

Spring collection 300 - 600 rear. 400 - 750 front:
http://gallery.me.com/meyermotorspor...&bgcolor=black

You can influence how your car handles by brake pad choice:
http://gallery.me.com/meyermotorspor...&bgcolor=black

Running a little excessive rear tire pressures is an easy way to help make the rear end of the car rotate. I don't like to do this because your taking away grip and we aim for as much rear grip as possible. A few additional psi is all you need: http://gallery.me.com/meyermotorspor...&bgcolor=black

Watch out for mechanical suspension interference. We found that some upper front control arms have a larger cast tab on them to hold a brake bracket. We ground them down so the spring will not touch/rub on the inside of the control arm: http://gallery.me.com/meyermotorspor...&bgcolor=black

New Grand-Am ST and SPEED World Challenge TC2 car: http://gallery.me.com/meyermotorspor...&bgcolor=black

MazdaSpeed BIG swaybar made by Speedsource. Sorry---best pic I could find. This is the bar I really like for street/track RX-8's. http://gallery.me.com/meyermotorspor...&bgcolor=black

thanks for all the insight to your experience and knowledge... will have to add to favorites for a re-read later!

Zoowie! What a shop! What cars! What a parts stock! What fun stuff to play with! I'm guessing this isn't your day job or else how to pay for all this! Couple questions...

..do you sell the delrin upper CA bushings and esp. do you sell the cotter pin quick release links? Are there unique front and rear links, or one link for all 4 corners?

Can you describe how and to what degree the delrin upper bushings helps?

MazdaSpeed BIG swaybar made by Speedsource - awesome!

-Thank you. We love our new shop extreme makeover.

-Delrin--never thought anyone would be interested. Let me think about making more.

-High-tech swaybar quick release pins made of moon rock and fairy dust. Go to Lowes or Home Depot with your existing bolts and end links. Buy the stoutest pins you can. Your existing sway bar holes may have opportunity to be bored out just a smidge to allow for a more beefy bolt/pin. Make sure your new pins allow for your sway bar to function properly.

-Delrin help. One of the reasons we run Delrin up front is to reduce stiction in the suspension. The following description of stiction may be a little advanced for some of you so. Don't freak if you don't get it on the first pass.

Stiction is the INABILITY of your suspension to freely move or travel. You can experience stiction when you set up your car and obtain different scale readings with the exact same setup. For example, let's say you're setting up your car with a target cross weight of 50.5%. Quick note: before we start going down this explanatory road, if you need a refresher on Cross weight--a great little article web link from Grass Roots Motorsports is provided at the end of this post.

OK....Let's pretend you've invested a few minutes in your setup and finally reach your target of 50.5% cross. For fun, you roll the car off the scales and then back on. This is done to allow the car to freely move and/or return to it's new adjusted state. Another way to do this is called "jounce". I don't know who the hell invented this word but just about everybody I know uses it when placing their hands on the car (when the car is on the scales) and pushes/bounces/leans on the car to get the suspension to move. After either of these techniques (rolling or jouncing or a combo of both) you look back to the scales to see your 50.5 You see 50.2 What? You do it again. New number: 50.7 Hmm?? Grass Roots racers I've found normally accept small variations in car weight. Perhaps 50.5 target and 50.7 on the re-read. Perhaps 50.5 target and 50.3 on the re-read. Some guys (personal experience) will setup their car, read the scales one time, hit their target number and put the car on the trailer. This may come as a shock to many of you but there are several Club Racers I know that NEVER get their car setup or do it one time at the beginning of the year or after a big hit or important race.

I use to setup my Spec Miata for NASA before each weekend event. Suspension moves. A typical Club racing car's suspension moves. Prior to each event we wanted to make sure our car was headed to the track with exactly what we wanted. For Road America we would run zero toe and less camber for the long straights. For Mid-O we would run more toe and camber. We would spend lots of time getting it EXACTLY perfect. EXACTLY. It was really hard and took time because we were perfectionists. We normally could get a 50.2 and then a 50.3 or 50.1 on the re-read. We would keep turning the shock collar just a smidge and about 5 or 6 tries and the scales would flicker between a 50.1 and a 50.2. Sometimes a 50.1 flickered 49.9 to 50.2. It may settle at a 50.1 if you held your breath. Close enough. Time for a beer.

Lets back up to about two years ago. We are setting up our RX-8's and I see that we are getting variances in cross with our new fancy scales from MK Technologies: http://www.mktechnologies.com/products/mkt3800.htm

I see that we are getting variances with this new beautiful setup tool. I call Marty. Marty is the "M" in "MK". Marty tells me its the car. He offers a story about "stiction" and a Daytona Prototype Team that was getting varied readings on their scales. Marty suggested they loosen their suspension and then retorque it when the car is at actual ride height. It turns out that a car (even a DP car) can have twisted bushings when you lock down/torque your suspension and this twist or tension can give you varied readings on your scale. Pretend that a corner of the car wants to push down (or pull up) and here is where you get these varied readings. We follow Marty's advice and our scale reading variances go down to near nothing.

So what does this have to do with upper control arm Delrin? Well, we figured out during the rebuild of one of our car's front suspensions that the control arm assembly (front upper control, spindle/upright, and lower control arm) did not freely travel up and down. We noticed this with no swaybar attached and the shock removed. Closer inspection showed us that the upper control arm bushings get pinched when they are tightened down. Noticed I said tightened down and not over-torqued. We had Delrin bushings made to allow for more free movement. Currently you can torque these guys down to spec and the suspension freely moves up and down when using your little finger.

Now when we perform our setups, jounce and roll the car, take multiple scale readings we see little to zero variation in our values. I have concluded that these bushings have helped us reduce from "stiction". This may be overkill but I want to get the car as near perfect on the scales as possible and be able to repeat this process at the track and for the return to the shop where we do a "set down" to see where we ended up. The more we go down this route the more we are able to drive the car knowing the exact setup that's on the car.

Note: We didn't feel that new rear bushings would be valuable in the Multi-link rear IRS. We felt that this would be both difficult and expensive to do.


CROSS WEIGHT ARTICLE: http://grassrootsmotorsports.com/art...orner-weights/

Happy rotoring

wow eric, just wow, i hope you dont mind if i PM you in the future for questions, you're one of the few on this form thats been there and done it all with the rx8. i applaud you sir

i work with a gentleman who used to autoX his 5.0L Mustang GT. His was completely stripped of any interior item except for a racing seat, and guages. He told me to go with a softer rear set up so that when you go around a corner, your rear end will lower down and put the weight on the outside wheel so that it grips better. The current set up i have now on my car, (i bought it used) is the stock springs and shocks, but i added on the hotchkiss racing front and rear sways. I have them on the middle setting, and when i went to lime rock park for a track day i've noticed that the car would push more so than normal. Now im sure if i had the proper suspension it would have made a difference, but some of the guys were telling me to just losen the front sways. I always go and talk to as many people as I can about setups and driving preferences but not often do I get to talk to people who have had vast experience. any reccomendations??

NOW WE'RE TALKIN'!

First off, a live axle Mustang has much different anti-squat characteristics then an IRS. Your friend is right as the pony cars hunker down when on the throttle in a corner. IRS is a slightly different animal. In a live axle you would want to square off a corner more than an IRS. An IRS will let you hold a line that has more of a radius

Before we make any conclusions, let's go down the basic path.

Please share with us as much info as you can about:
-Hot tire pressures
-Tire temps if you have them
-Which corners the car is understeering
-Where in the corners is it understeering (off brakes, turn-in, mid-corner, back to power, exit?)
Any additional info would be helpful.

Also, what course configuration and track conditions please.

Aren't you a Mazda Motorsport member? :dunno:

https://www.rx8club.com/rx-8-racing-25/new-rx-8-suspension-race-parts-mazdaspeedmotorsports-157592/

Not presently. I don't believe I meet their definition of 'racing', not sure. I suppose I could be building something thou...

BTW good description of 'stiction' Eric... although I can think of few quicker explainations lol

this is Eric---we are lucky to have him and his knowledge around.
never knew you did mustangs--people around are claiming i am trying to turn my 8 into one.
Any suggestions on aerodynamics? Above 125 and still accelerating--- i dont like it.
I am trying to sort out mine (suspension)now --motor now replaced and broken in, By the way we have learned a lot about lubrication issues lately.
Details to come and i know you are the man to ask.
rotor on dude
hope to see you at RA.
olddragger

Yo Denny. Always great to hear from you.

Aero suspension sorting. We are planning on sorting out our new nasty bitch in the new future. Our plan was to have it ready for the Dec. Road Atl event however Daryl Drummond has some custom intake issues and we're running behind schedule.

RX8 w/custom RX-7 motor: http://gallery.me.com/meyermotorspor...&bgcolor=black

Note the big front splitter, 255 tire and rear wing. We will also run about a 2.75 - 3.0" ride height. Front splitter extends back to front axle.

Here is our logic we plan to follow after talking with more qualified drivers, our drivers and reading a bit.

Our plan is to seek out a few tracks that have some different types of high speed terrain. Since aero comes into play at higher speeds, you'll be using these high speed corners as your test bed.

Set up car as you normally would using previous best setup or best guess. Keep in mind that a lowered car with an extended front splitter may interact with ground and/or curbing more than the past. When we chose our splitter size the best advice I got was this: "bigger isn't always better when you hit something and tear off your front end". So we chose to build something that we thought was big but not too big.

For Road ATL the primary feedback I'm looking for is what the front nose is doing in the various braking areas. I'm anticipating much more front grip. Better than our seat of the pants sensor we have shock pot data collection which will tell us the behavior of the car's ride height at both ends. Additionally we will be able to see small variations in front to rear wheel speeds which may be master cylinder issue (which are new to our ABS system).

I know from Daytona that the front MazdaSpeed nose produces lift---about 3/8" at high speeds. I think we saw 141 mph terminal with our 5.12 ring and pin at 8,900 rpm pinging on the bosch soft rev limiter. We raised the 6th gear limiter for this. Normal limiter is 8,500 soft cut and 8,700 hard cut (because there is no power and/or power loss above 8,700!!!!!!!!!!!) That was a note for everyone. THERE IS NO NEED to drive your car beyond where the power falls out. There is NOTHING above 9K Quick note: next time your on the chassis dyno start recording your pull in 1st gear, run it up to about 9K, shift to 2nd and continue to 6th gear. Caution---engine will get very hot. Make sure you have twice as many cooling fans as you think you might need. We use 3 commerical fans people use to dry out basement floors if you have a flood (about $140 ea). This will show you where your rpm drops and what power is there. Try it a few times: shift at 8,500, 8,700 and 8,900. See where you are in the power. Try it at 9,200 if you want. You'll find you're operating in a lower power range.

OK, so we know that the nose may produce lift. We also believe that the front splitter will produce neg. lift (fancy aero word for downforce). We also believe the rear wing to produce neg. lift. The plan is to confirm the car's suspension works in the slower to medium stuff (we have installed yet another larger sway bar and reduced spring rates by approx 15%). So confirm the car works in the slow to medium stuff paying specific attention to Turns: 2, 3, 4, 7, 10a/b. Myself and another driver or two will drive the car. The more feedback the better. It will probably be Jay and myself (Jay is the Hawk Brakes distributor, co-driver and team member) We have slightly different driving styles which will gives us additional feedback. So we will get the car working in aforementioned turns. Now it's on to really pushing it around the rest of the track to discover where the car wants to give in first---the front end or the rear. The front naturally would be push or understeer feedback, the rear would be oversteer. You can tell we've been talking about this alot. Road ATL was one of our best choices due to the various high speed corners the car is exposed to. We thought we would have our new engine by now, installed and ready to test---nope.

Here is what I think we're looking for Denny:

-What does the car want to do apex out in T1. This is an uphill and cars get compression here. What does the car want to do. I suspect we could really, really hoof through here way more than we have in the past. The challenge will probably be driving fast enough through here and combatting the previous mindset of "I can only go XXX fast through here).
-High speed push through the esses?
-T5 crest. There should be an unloading here I think. What does the car do?
-T6 heavy cambered. I suspect we should be able to haul balls through here and my gut says there is alot of wrestlng the car down to speed to make T7. I wonder what the ass end is going to do here under braking.
Braking into T10 series paying particular attention to the height of the rear end. Remember, we have shock potentiometers to actually measure this. Does the car need more rear wing here? I'm hoping the new location of the dry sump engine (lower and slightly back) along with a new 32 gallon fuel cell in the trunk will work to our advantage. Dunno. Will find out.
T11-T12 I can only guess the car may want to push through here. We will see.

I buddy of mine with a 700+ hp Mustang NASA AIX rocket/beast/spin the tires at 100 mph thing) suggested we try the car with and without rear wing to see what the straight line data says and what the car does. We plan to do this as well.

If I were you Denny I would plan on pushing your car to it's limits and listening to what she says.

We then plan to run it at Mid-Ohio as there are some different types of corners there that should also tell us something. Mid-Ohio track map: http://www.trackpedia.com/mediawiki/...fc/MidOhio.jpg

Oh....the suggestions I got from several drivers was to drive tracks you are very familiar with to do this high speed sorting. Avoid tracks that have a bunch of slow corners and straight straights. Find those with high speed variations. Mosport would be great.

For Mid-O:

T1---how fast can you go/what does the car do?
T7 braking
T8-10 complex
T11 if anything at all. T11 leads to a higher speed complex so anything gained here is probably great time. Same for retaining speed through T12 which has a nastly trackout followed by braking earlier which has that big hump there. Again, all high speed evaluation thought process.

Probably head to Road America for top speed and gear testing (with and without wing). Same for Daytona with SCCA in early May.

Hope that helps. Let me know if I can help. I would need to both ride and drive your car to get the best results. Share your current setup when you have a free moment.

E

scribed for reading-

Sweet Eric- thanks bro.
Road Atlanta--Turn 1--you have to trust the car and banking?--lot going on with outside compression and acceleration progressing to a cresting the hill scenario--roller coaster stomach anyone? Bump stops here--watch them?
Do most not go wide enough before entry and then turn in too soon here?
Yep watch that front end splitter on T3 entry.

softer spring/shock setting will help coming out of turn 5 and the rumbles?

turn 6--actually trying to do a lot of trail braking here--think i need a diff brace-- the rear end can get a little squirrely on initial braking (all corners)--can gain a lot of ground on others by doing this here but cant catch many between the short section of 6-7.
T7-- push coming out--always --until i convert to 4W drive lol.
T11-12 --i need more testosterone--dr's appointment soon.
i can hit 140+ (power baby!) on the long back straight but havent allowed that to happen yet--car doesnt feel stable above 135 or so. Heck hitting 136 @ Roebling.
That rear wing will work--I bet ya. Front I am interested in.
Interested in seeing your option on this with all the date collection ability you have (Santa must think you are a real good boy:))
You verified what my butt was feeling about high speed lift.
Any underpanels going on?
Sorry you cant be at RA in Dec--was looking forward in seeing ya--should see the clubs calender we are doing--its really sweet.
We are also doing side by side vids to review by--nice. have a outside theater for afterhours track vid viewing
Reg RX'8s with aftermarket coilovers and used r compounds are getting to 1:47's or so while their heated seats are on. Then drive it home. Who would have thought.
Speak soon.
One day I will have a flat black car if Santa thinks i have been a real good boy.

YOU ARE THE FLAT BLACK KING DUDE! Love that look:)
new wheels are nice also.
OD

My notes below


thanks.