whats best --tuned cz or light flywheel
 

All,
I'm at a crossroads here. Need opinions. What is the best for acceleration? A custom tuned cz unit or a light flywheel(rb's, act's etc). I know there are other variables, but for this thread, just an acceleration comparison. Two stock rx8's. One with the tuned cz, the other with the 12lb flywheel. Which would be the first at the end of the strip?
thanks
olddragger :)

A flywheel is not going to free up more then 5-10hp in 1st gear and will be next to nothing in 3rd gear and above. A properly tuned cz would give you 10+ hp in every gear.

ok thanks prober. so the cz wins?
olddragger

From what I hear the CZ is barely even distinguishable when it comes to acceleration. They had to film two rx-8's tachometers and put them side by side just to prove that the one with the CZ accelerates faster.

Everyone who has had a light flywheel installed has said it has done wonders for the acceleration.

It's not a matter of adding HP per say, but the car has an easier time spinning a low mass flywheel, especially because our cars rev so high.

I'd say flywheel.

I would say the flywheel since you are only talking 1/4 mile. How many shifts are we talking about here?

I pondered that very same question a week or two ago. I had a chance to purchase a used cz with the software, but I wanted a flywheel. I opted to not buy the cz because I am going either GReddy or Zex. So, the flywheel is my next purchase. In fact this is the week of my PO.

I'm going to follow this upgrade path to my car:

Mazdaspeed Flywheel
Hawk Pads
MS SS Brake Lines
SR Underdrive Pulleys
Zex Nitrous

Then when these are ready:
Richard Paul's Short Shifter
Racing Beat REVi Intake
Charles Hill Headers (or another brand if they don't work out)
Bonez High Flow Cat Midpipe

And last:
A Mild Street Port :)

remember I'm not speaking of the plug and play cz I'm speaking about the customed tuned cz. People swear 20-30 horses with a tuned cz. People also say the flywheel really wakes this car up. Im just trying to get peoples opinions.
Nemasis I would not get the mazdaspeed flywheel . Too expensive and doesnt save enough weight. I know people who have both and there is a differance. AND dont worry about the warrenty.
before you get the break lines and pads get the mazdaspeed front stut brace so you can brace your mastercylender. The dang things actually MOVES with hard braking.
.
Dont forget the aftermarket sway bars/springs or you will have a hell of a lot of wheel hop

Do your own oem intake mod for about 30-40 dollors . It will be just as good as rb's(i like rb's stuff its just it will not give you a significant increase in power) I like rb because they have high quality stuff and they are honest about it.
olddragge

Thanks for your input.

The cz I almost bought, was from a member that is installing the GReddy TC. So, he must think that the TC is a better solution than the cz I guess.

On the flywheel, should I get the SR, ACT. or which one?

I have the Mazdaspeed strut tower bars, sway bars, shocks, and springs already. See my sig :)

Should I get Mazdaspeed or Goodridge Brake lines?

This one has me stumped, "Do your own oem intake mod for about 30-40 dollors?" What did you have in mind for this one?

right now we swear by the act flywhweel. the entire package flywheel,counterweight is only about $350 (total weight about 12lbs) and it has all the good features. The light flywheel is actually a 3nd gen flywheel and the counterbalance weight is from a rx7 automatic . Seriously!
Brakelines doesnt matter whichever gives you the best deal. on the intake do a search under custom intakes and you will see some diy threads where we have rerouted the air intake to be a true cold air intake , we have modified the vfad and we have placed cone type filters into the stock box and modified the inside of the box. It does make a differance and it's not too loud. Some of us have modified the top cover of the stock airbox with plexaglass. Looks sick
olddragger

I think the Stage two would win by far. The other benefit is ease of installation. You can install the Stage two in less than an hour.

Vince

Nemesis, How come you are not thinking about the RB flywheel ? Also I know Unorthodox Racing has a rather unique design on their lightened flywheel where the counter weight is built in so you may want to check them out.

Personally I would probably do the tuned Stage 2 CZ unit. That way you hp across the board. Whether it is off the line (where the flywheel would help too) or at freeway cruising, and you drop it down into 4th (where the flywheel would not). And I have the flywheel which I love too. The best answer would be both. but if you could only have one I would do the CZ tuned unit. If you are thinking about the SC/TC later then do the flywheel and leave yourself open.

OK, sounds good. Now back to your question - I thought it was the stage I you were talking about. So, the tuned one should do the job - I'll agree with Vince and now say CZ wins!

I'm having decision constipation I guess :p

OK, it's either the RB the SR or the ACT.

That's exactly what I want to do. Either TC or SC eventually. My funds are low at the moment - had to get the wife's Passat repaired this month, so I am going to have to wait till next month to get the flywheel.

I have not read much about people's impressions on upgraded flywheels. The most I've read about it is that it makes the revs easier but nobody ever says that it's a beast after the upgrade. Now for CZ, my car has pushed me to buying new springs because the wheelhops are amazingly annoying now. I'm not saying it equals Philodox's turbo, but just watch his video. You'll notice how easy it is to get bad wheel hops with this car when it is punching non-stock power. A bravely-tuned map like mine (not well-tuned) could really pack a punch. I'm still scared to high rev it long because I have had it shut off throttle for a second at high rpms. Probably because it was running too lean. I still haven't had time to fix that spike in the map.

Still waiting for next summer to tune it again.

True, if you get CZ and tune the maps it will be a waste when it is time to get the T/C. If you're getting the Greddy, then you will be required to replace your CZ with the Greddy tuned E-manage unit. Even if someone here publishes the map, you would still get that Greddy tuned unit because you can't exclude it from the kit. It comes with it.

Short-term, CZ wins. Long term, get the Flywheel.

Since I have never actually ridden in a well tuned CZ equipped RX-8 (not yet at least) I can't speak for my impressions if it. I can only speculate what "should" happen. However I have had flywheels in the past and I can say from experience that they transform your car into an entirely different beast. A difference in acceleration is quite noticable. The engine is mroe responsive and you'd almost swear you had a race engine under there. A light flywheel makes the car alot more fun to drive. Is it faster than a properly tuned cz box? I can't say but you definitely won't be disappointed with one.

i've had the cz w/o the flywheel, both on, and also without cz and just flywheel. CZ is definetly a good buy, gives you a little edge above stock. But I notice way more difference from the lighter flywheel. Car revs so smooth and quick especially in the higher rpms it feels less lack of a better term "choppy". Feels like you're accelerating a lot faster but in actuality it's probably a nominal difference in acceleration. For track racing I recommend flywheel easier to keep the revs in the powerband, on a drag strip, cz probably gets the nod.

great summary/opinions guys. I appreciate it. I think one thing that makes this car so cool is this forum. Seriously, I would not have enjoyed this car nearly as much without it.
So :advantages are
1-tuned cz = power advantage over flywheel,20 min instillation,many people will help you tune it
2- flywheel has some power and makes the car smoother and more responsive therefore changing the character of the car to something better
disadvanges:
1- tuned cz- have to run 91-93 octane gas, will reduce the life of your cat to approx60,000 miles, tuning time and learning curve in doing it
2- flywheel-- cost getting it installed, driver adjustment period in starting etc(doesnt take long)
Hmmmm-- is that the way everyone sees it?
Still ---- a hard choice. Since I have a stock cz stage 2(haven't custom tuned yet) I guess I'll get the act flywheel installed before my next trackday before I invest in the equipment and time in custom tuning my cz. Ya'll been a big help in my decision.
olddragger

I have ran my CZ stage 2 map (unmodified) on Chevron 87 and didn't have any problem. The only thing I noticed was I run out of gas quicker than when I'm running 91. Smaller MPG pretty much.

i tuned my cz map for 89 octane... and i still have a 10-15rwhp gain over stock

When tuning the CZ you can set it for any octane level. It is about when you detect detonation. When you are running an 87 octane level you just have to dial down the degrees of advance. You won't get as much hp, but like Prober said you can still get good gains. Later if you decide to run on 91 you can turn it up and gain more hp.

Couldn't you just get a GReddy e-manage and tune the crap out of it (leaning and increasing ignition timing) rather than a Canzoomer? Seems smart cuz it takes into account all your current modifications at the time of tuning.

Canzoomer seems too plug+play.

From a set of "before" vs. "after" numbers taken off a Dynojet ~ SAE adjusted, and just to take 5,2xx rpm since that's the bhp/torque cross over point, without trying to pick any one peak bhp/torque rpm point (which, FWIW, peak values were in the 177 to 181 bhp or so, and 135 to ??? ft/lbs):

2nd 3rd 4th
bhp ft-lb bhp ft/lb bhp ft/lb @ 5,25x rpm
RB LWF 124.0 124.3 129.6 129.9 131.2 131.5
Stock 115.2 115.5 123.7 123.9 126.5 126.8

Gain/Loss + 8.8 + 8.8 +5.9 +6.0 +4.7 +4.7 in the 5250 rpm range.

Theory would suggest the "accelleration" gain in first gear would be something greater than the +8.8 bhp or ft-lbs the dyno measures for 2nd gear. There are other ancillary benefits claimed for the lighter roataing mass, i.e. easier shifting, less drive train wear/strain for miss matched shiftes etc. but those points can also be argued both ways I suppose. There is a theoretical gas mileage gain to be had, but if so, I can't say I've noticed a night vs. day difference, and if there was one, it's probably been obsured in the several ECU flashes that have taken place since the light weight flywheel addition in September of last year, 2004, and the (in our area) winter change over to oxygenated fuel &/or my new all season (better rain &/or snow protection) tire selection.

HTH
miike

Oh yeah, FWIW somewhere on this list I posted 3 either pdf's or a jpeg with the dyno charts for each pair of gear runs ~ the gap charts fairly consistent all ther way across the rpm range from @ 3k where the data acquisition was triggered to @ 8.5k where we stopped the runs.

mlx8,
great info man. so there is a gain across the spectrum. Lower gears showing the greatest which is to be expected. Solid stuff. Appreciate that. Your other points are well taken also. the rb is compatable to the a.c.t. flywheel I am interested in.
prober, fanman and cretinx -- Yea- I realize that the cz can be tuned to run on 89 octane but I was just going for best case scenario in the comparison.
When i was running stage 1, 89 octane was not a problem. but when i kicked up to stage 2 I have a little studder problem at about 4k with a light load and partial throttle.. i havent backed out the timeing advance below 5 k that comes with a stock stage 2 map. I gotta do that as i understand that corrects that issue. Stage 2 I ran 93 oct all the time
Further summation with the new info is :
1- With a tuned cz and a 12lb(approx) flywheel one can expect a 30-35hp increase?(basically speaking)
2-Tuned cz wins the hp battle agaisnt the flywheel.
3-untuned cz is then about equal with the flywheel.
ok then .
futher opinions anyone?
olddragger

I think you covered all bases. All members that have installed a lighter flywheel have said the same thing, they wish they would've done the mod sooner. With a 9k redline, a lighter flywheel is a must. It feels you can move the car in every gear, can't go wrong with buying one I tell ya.

Installing a lighter flywheel makes your car a bit tougher to drive though

After my flywheel/clutch install in the Celica it took me about 30 minutes to relearn how to drive the damned car.