emailists

I recently have had the opportunity to take a ride (unfortunatley I was not able to drive either) a Greddy turbo'd Rx8 and just a few days ago visited Pettit Racing for a ride in their supercharged 8.

I don't have nearly the amount of details I'm sure people would like, but I can offer my butt dyno impressions of each ride.

The turbo belongs to Phil, a member of this forum, who I think posts under a handle something like "Veilside."

His green 8 is quite something to behold. Aside from the Veilside full body kit, he has a full variable suspension and I believe the car is dropped almost 2". Handling felt excellent on the short highway drive we did. He also had a custom pod guage on the A pillar, which looked excellent. Both his car and the Pettit had catback exhausts.


My impression after the ride was "damn, I really need to drive this thing to compare how it felt against my stock 8." There was definitely the feeling of a more powerful car, and he indicated the boost does come on quite early. I also noticed he didn't seem to be using the upper RPM range, the way I do in my stock 8.

I came away feeling that at the price, it's a worthwhile upgrade, and something I would love to do. I thought I had heard it mentioned that there is a certain notchiness or jerkiness to the turbo'd setup at some rpm, and I seemed to remember feeling this, but only vaugly. The install looked great too, with polished piping under the hood. Phil's car is in Rockland county, NY.


Reading the Pettit thread, I realized they are near where my parents live in Florida, and called to tell them I'd be in West Palm Beach and would like to visit them.

I commented to my girlfriend as we pulled into Pettit's shop that we've arrived at Rotary heaven. The parking lot was filled exclusivley with RX7's and RX8's, all in some form of modification.

Candy, the female engine builder, gave us a tour of the facility, and showed us some differences between various rotary engines, and the different seals and ports of the RX7 and RX8 engine. Even my girlfriend, who has zero interest in this stuff, found it interesting. (She does drive a stick however, so I can't complain.)

Finally Cameron, the owner took me for a ride in one of the 2 prototype charged 8's. He is very upfront about the fact that it is very much a work in progress. Like everyone else, he admits that the ECU is the major hurdle, and indicated that other turbo solutions on the market have some huge issues he would feel uncomfortable with selling his customers. I believe he has also provided some assistance to them with tuning issues. Incidentally both he and Candy mentioned that they feel there will be increased engine wear with turbo'd 8's, as opposed to Supercharged 8's. Candy showed us some points of wear in an 8 engine that I believe was turbo'd before being torn down.

The car we took the ride in had the inercooler removed, due to some mods they are doing on it. Cameron thought the intercooler would add 10-15 hp to the car when it is back in. The car did have a cat back exhaust- which he felt added 10 hp, so maybe it was close what you'd get from the final kit, without an exhaust.

One thing I noticed was that the car was not loud at all. There was some induction noise, and he indicated that would probably get quieter inthe final install since they'd retain some of the airbox. There was also some exhaust noise, which wasn't too bad either. My Probe GT '94 had a Greddy catback, and K&N conical intake, and that was considerably louder.

The idle of the 8 we were in was also some issues, and I noticed he gave it some throttle at idle to keep it from bogging. Clearly they are still working on it, and all will be resolved before the product is offered for sale.

What I did come away with, was a clear and unequivocal feeling that I didn't have to drive this car to know what was going on.

From a dead stop there was simply so much off the line pull, I started to get a tiny bit nervous. The amount of pull in 1st and 2nd is oustanding! I really don't know why I didn't come away from the turbo ride with the same feeling!

On Pettit's 8, there was so much power, the back end felt a tiny bit unstable- though it never wheel hopped. Cameron did mention he had to disable (via holding for a few seconds) the DSC and traction - since the blown 8 didn't like DSC/traction when going full tilt.

This kind of power is exactly what I am looking for being a city dweller. I need more off the line performance, and am not as concerned with top end power.

Now what I did notice on the Pettit car was that 4th gear for example, down low didn't seem to have nearly as much get up and go as 1st & 2nd. This seems to be the opposite of the Greddy car I was in. The installer of the Greddy car told me when delivering one car he did, he one kept it in 5th on the highway and was easily able to pass people. He didn't have to downshift to pass.

In both rides I noticed the driver was not often revving higher than about 6K, which is really interesting that you simply don't need to drive the the engine to the upper RPM's like you do with a NA 8.

In the Pettit car we didn't get into 5th or 6th. Cameron also indicated that they were getting better MPG with the supercharged car than stock. That seems in contrast to what turbo owners are finding.

Athough the battery was moved to the engine wall in the Pettit 8 we drove, Cameron said it very well may be able to stay in the stock location.

He couldn't give me a clear indication of price at this time, but did mention they were going to try to keep it at what the Greddy was currently MSRP'ing at.

Needless to say I am very excited to get this system. Pettit said they may also at some point offer a turbo car, but had no details.

It seems they are in no hurry to rush a product to market that is not completely solid, fully tested, debugged, and is in no danger of blowing seals.

I almost forgot..... The pettit car had an underdrive pully and lightweight flywheel on it. Could that have been responsible for some of the off the line pull I felt, maybe so.

He said the kit would be about $5000 and would be important to avoid transmission and clutch troubles due to the added HP of the SC.

Phil, the turbo owner also mentioned he was planning on putting in a high performance clutch, since he and the installer felt the stock clutch was the weak link. The clutch would be about $1000, plus install, so if it's true that the lightened flywheel will take allow the stock clutch to stay put for a while, it seems like a good deal.

Cameron also mentioned they are using a very sophisticated European compressor, (I don't remember which) whoose innovative design had one set of blades traveling twice as fast as the set it interleaves with, and that have it a whole set of advantages over other designs. (I wish I had gotten more details about the compressor) I also really wish Richard Paul's Axial Flow was closer to market, to compare the two. I am fully convinced that supercharging the 8 is the right move for what I'm looking for.

Since it won't be availble for a few months, at least I have a chance to save up for it. I really want the Pettit system as soon as possible. Maybe I shouldn't have ordered that 30" Apple Cinema display (and it's required $500 X800 video card for my G5) I did just before seeing the Pettit car. That's the price of the kit right there.

cgrx

nice write up !

rotarygod

A light flywheel on it's own definitely helps lower gear acceleration. The supercharger they are using is the Autorotor twin screw unit.

I saw their system at Sevenstock last year and admittedly criticized it. It was a very early prototype though and they have done very good work in the past. I was overly harsh back then. It's good to hear that they are going to do it properly rather than quickly. Too bad those 2 can never go together. I think the supercharger will be a very fun addition to the car. This should actually give the auto guys some promise as their engines don't rev any higher than where these cars were being driven. The auto already makes more power than the high power engine up to about 7K rpm. This could be fun for them. Good to hear. Stop by there every once in a while and give us an update.

Charles R. Hill

iTrader: (7)

Tell Phil to save himself some money and drive to Detroit where I'll do the install for free. He can get a light fly and decent clutch kit like the ACT I have and still have several hundred left over. I have references.

CRH

IZoomZoomI

nice writeup thanks for the update!

Greddyturbo1

Emailists, Afew observations here.

1. Your obviously biased for pettit

2. If your not, then the Turbo you rode in was sick that day.

3. My Greddy turbo with the high flow cat was dynoed at 274 at the wheels with just alittle tweaking, and I can smoke the **** out of my tires.

4. I will guarntee you the Pettit's supercharger won't touch my car and I'am not done yet.

5. I have done my homework well and will tell you the size of Pettit's will never compete with the Greddy or SFR/SSR turbo.

6. I'am not saying anything about Hymees or Richard Paul's those are bigger and different than Pettit's, and when they are done may very well be the best of the best, we will see.

emailists

Greddyturbo,

are you running standard maps and boost? The car I was in was stock from Greddy.

I'm not biased towards any solution, I can only report what I sensed, and of course my desire for low RPM power off the line.

Icemastr

1. He rode in both and gave is objective comparison. Some people like turbos, some people like superchargers.

2. I doubt the turbo car was sick he just didnt like the way it felt qute like the supercharger, doesnt sound like the owner was pushing it too hard nor making use of the upper RPM range.

3. 274 whp is pretty decent but nothing to brag about. Thats barely a 50% increase over the stock output, easily doable by a supercharger kit. The custom turbo kit on my Miata is making 215rwhp at 11 psi. I could buy a twin screw supercharger kit and be making the same at about the same pressure but I didn't because I did the turbo kit for under $1000 rather than spending $5000 on a kit from a company.

4. I see no reason pettits supercharger kit shouldnt be able to make a solid 250-260rwhp with a great torque curve when its released which I am sure would let it keep up with your car just fine.

5. How do you know Pettits supercharger will never compete with the turbo kits? Some people want different things, all out peak power means nothing to a lot of people. I would take a supercharger making 30RWHP but making 50%more power through 1/4 of the RPM range vs the turbo anyday. Not to mention better throttle response.

6. Pettit is hardly done with their supercharger kit, they could still change the whole supercharger they are using. How do you know how big the supercharger is? It seems to be sized about right to me. Do you details and specifications on the supercharger? Do you know its peak airflow numbers etc.?

A lot of things can and probably will still change in the Pettit supercharger kit. In addition I bet I could probably take a stock RX-8 with Pettits supercharger in its current form and beat your car with the turbo any time at an autocross event. However that doesn't matter a whole lot to me because I wouldnt want to compete with an RX-8 in SM2 weight 3000lbs and 270whp when I am driving a 400rwhp 2600lb RX-7 with much better response and a way better torque curve than you can hope to get with your greddy kit.

Bindon

Amen.

Fanman

Sorry, but you are way off on a few points. A regular RX8 dynos at around 170-180 whp, so 274 whp is a mammouth acheivement. That is nearly a 100 whp more than stock, an almost 60% improvement, not the "nearly 50% that you are claiming. The Pettit claims are for around 50 whp for their "high boost" version. Even if they get to that 50-60 whp gain (closer to 230 whp). If they are charging $5000 like their original claim that will not be cost feasible. At that cost point the SSR/SFR turbo becomes economically viable & they are looking at 280-290 whp, a massive 110-120 whp gain.

A Greddy Turbo car, does not deliver power strictly in the upper rev range. As a matter of fact it is delivering power/boost at 3000 RPM. It has more to do with turbo sizing. The tq curve is flat from 3000 rpm up (from the recent RX Tuner magazine article) delivering 190+ lb.-ft. of tq to the wheels). The SC unit from Pettit, from what I have seen is very nice. & is designed to deliver linear power vs. top end/centrifigul types (Sunflower/ATI unit).

I am looking forward to more FI options coming out for this car. Pettit's unit has been prototyed for a long time. I hope they come out with good stuff. I know they took a beating over the MT article that came out a while back.

Charles R. Hill

iTrader: (7)

Let's not let this mutate into another "super vs. turbo" debate. That has been done already. Icemastr has a load of experience with turbos and his opinion has some merit. The matter of discussing h.p. numbers also needs to be clarified by discussing flywheel h.p. as opposed to rear wheel h.p. Either that or we can define for the sake of argument how much driveline drag we factor in, in terms of fixed h.p. numbers and not percentages. If we don't settle some of these issues, first, the variables are far too many to ever come to any conclusions in our discussion.

I have my own numbers that seem to work pretty well for me but I'll allow someone else the floor to start that discussion. BTW, 274 h.p. is a decent number but I tend to agree with Ice that it is not much to brag about except to say that we have discovered a tried-and-true couple of ways to get there.

CRH

BTW, Fan your car and mine are darn near identical except for the turbo vs. nitrous and your 19" wheels. It would be cool to do a comparison someday. Thanks, again, for the manifold. That project will come over the Summer as I have another one I REALLY want to get started on with the trans.

Greddyturbo1

Charles R Hill, your right I don't want this to be another debate. But.

1.Icemastr, mine is making this power at 8psi.

2. The Pettit supercharger is making 220rwhp, ask cam. The car runs out of power after 7,000rpm's, ask cam. The Pettit charger is too small too make the power your talking about...

3. Don't believe me , ask Cam, ask Hymee or ask Richard Paul

4. I do like superchargers, I would have preferred one, but this one is not going to make the power I want..

5. Maybe Hymee's or Richard Paul's will, then I will review my options...

Fanman

Just got my Centerforce clutch yesterday. Might put that in somewhere down the road.

emailists,

What is interesting is that for S2000 development they actually ran into the opposite issue, as the SC's were breaking cars, while the few turbo options they had did not deliever as many issues. Just a particulary interesting point for me, as I figure that car is about as close a comparison to our car as is out there right now (light, high revving engine car). Had issue with SC's pushing the diff through the pumpkin housing (which was later reinforced). Not sure what the difference on engine wear is currently as nobdoy has put that many miles on their car/worn out an engine with a TC or SC. I certainly respect Pettit as a maker of fine modified cars. We actually had a thread on this subject a few months ago on who will be the first to blow their engine (just for fun) :D .

Charles R. Hill

iTrader: (7)

I don't mind debates, at all, but to keep it on one specific point, and one we have yet to cover, would be better for all of us. I would say that most who will respond to this discussion are those with a little more knowledge than the average RX-8 owner and I would prefer an opoportunity to learn from all of you instead of arguing the same stuff again. Greddy, if you are saying that 220 rwhp isn't much, I agree. I have that without nitrous and those are NET numbers. Another thing to consider in comparing these two particular systems is what the engineering objective may have been. Petit's system may be doing exactly as they would like, at least so far. Same with the GReddy system.

CRH

dmp

I'm wondering why Pettit claimed 'more wear and tear' with a turbo, rather than an SC...anyone have any data to back that claim up?

Boost should affect things pretty much the same...with the weakest? point being the apex seals. eh?

Charles R. Hill

iTrader: (7)

I'm guessing the difference is that supers are usually set to deliver their boost at high rpm's while turbos can bring it on sooner, so turbo engines spend more overall time under boost(?). Perhaps more heat with turbos, too.

Hey Fan, I didn't catch the full discussion on who would be the first to blow their engine. Did anybody happen to pick me? I figured with my reckless abandon for detonation, fuel cut with the nitrous on, second gear at 80+ mph, and wheelhop with the nitrous on but not letting up, I might be a good candidate to win that contest. Problem is, this damn Renesis/RX-8 is stronger than I am! :p

CRH

SHOWOFF

The main question at hand is what good is all that power with limited reliability. I would rather make 60-70 safe HP from Pettit than 110-120 Apex seal blowing horses and have my car in the shop more than I can drive it.

I too was in West Palm last year when Candy and Cam started tearing down Candy's 8 and started R&D on their S/C kit. They really know what they hell they're doing. These guys build GT motors that must run for long periods of time at extremely high temps and work loads. They stress reliability with their products because their race cars have to be reliable.

Lets face it you can be the first one to market and make great HP gains but once your customers start losing engines, the general public is going to lose intrest in your product.

I'm not bashing Greddy because I would consider their product if it has a great reputation in a few months after people have really had a chance to log some miles with their kits. If Pettit has torn down a turbo'd engine that shows heavy wear then that makes me wary of buying a Turbo style kit.

DARKMAZ8

Actually I would think that a supercharger strains the motor more than a turbo would. Considering the super runs off the engine.

JOHNRX8

30" Apple Display...YOU BASTARD! NICE.

cretinx

To kind of silence a few things,

my turbocharger feels like a supercharger (have no exhaust)

boost comes on about 2500 rpm and the torque curve matches that of a supercharger - it jolts up at 2500 rpm and is DEAD FLAT to redline, I mean like a straight line from when the turbo comes on to the end - full torque all the way through.

As far as the lesser gas mileage, on the city when I'm on this car hard, gas mileage is about 15 mpg (i have monstrous tires too that suck up lots of gas)

On the highway I've been getting about 24-25 mpg with the turbo, simply because the car is barely working to move. Yes, in 6th gear, tap the gas just a bit and the car FLIES past anything on the road. The only way the supercharger is getting better gas mileage is if it has superior tuning, or if its running less boost. Boost is boost whether it comes from one source or another - and I'd figure it would get worse gas mileage due to the parasitic loss of driving the supercharger.

I am totally positive with exhaust and a high flow cat this car will be a rocketship.

My main gripe with the superchargers is that they have parasitic loss - they're simply not as efficient as a turbo, and the general benefit of a supercharger - a nice flat torque curve - can be had with the GReddy turbo, which is dirt cheap, and frankly, will make more horsepower at the same level of boost than a supercharger due to no parasitic loss.

The only thing that could make me lean towards a supercharger is cost - my friend has a Miata and he got the Jackson Supercharger because it was cheaper - and yes it doesn't make as much as a turbo, but with that extra $1000 he can get an exhaust, header, and the Jackson high boost kit which should exceed the output of the turbo he considered.

Icemastr

180 + 50% = 270. Not to mention the owner said he did a few modifications as well.

Boost at 3000RPM, even your peak boost target at 3000RPM is good for a turbocharger but it is not near peak torque right off of idle nor is it peak boost at 1500RPM. You are also forgetting a few things, peak boost does not mean peak torque, there is also a thing called boost response which is how fast your turbo spools when you are off the throttle and your already at the rpms your turbo would spool up then you step on the accelerator in addition you have throttle response which is how fast the charge pipes and intercooler fill up to volume before your intake becomes pressurized and you start putting the power to the ground. These are all areas where the supercharger has a big advantage, its not just the powerband below 3000RPMs. Your going to tell me about turbo sizing and how flat the torque curve is? I have 8 turbos sitting in my garage right now as well as several intercoolers and various other parts. I slap turbos on cars just for the heck of it like my 89 dodge caravan. I co-drive and help with an SM2 car that has the best power delivery of any turbocharged rotary I have ever seen in all my years because of its ECU tuning and proper setup. It does things people think no one could do on the stock turbos and goes against the accepeted with many of the modifications it has.


Pettit will come out with good stuff. The original posters comment about the supercharger kit being priced similarily to the Greddy kit certainly makes things interesting. For comparison an 8 psi 1.2L Whipple supercharger kit makes 215rwhp on a 1.8L miata motor. I find it hard to believe that a larger supercharger on an engine that makes 80 more whp stock barely makes the same HP at the same boost level. There is no reason I can see except possibly the ECU that a supercharger making over 250rwhp isnt feasible. I am not bashing the greddy kit as I am very impressed with what it does for the price, my opinion is for people considering forced induction is to listen to people with all different types of products and talk to people with experience on various setups and try and drive a car with one of these setups before making your decision.

Positive displacement superchargers (Which I think the Autorotor is) deliver the peak boost at pretty much any RPM. I am not sure why Cam and Candy are saying this but my opinion in experience would be that additional wear and tear from the turbo over the supercharger would be increased heat in the engine bay and to the engine due to having a turbo attached to it and additional stressed placed on the oil and cooling system due to the added demand of having to cool the turbo. Many low boost superchargers are self lubricated and do not generate the heat in the engine bay that turbochargers do. Both will add heat in the intake charge due to the creation of pressure and often times positive displacement superchargers have higher inlet temperatures than turbochargers.

Have you driven a supercharged RX-8? If not then you cant make a comparison that your turbocharged car feels like a supercharged one. As I mentioned before there are differerent ways the car will drive between the two that you can't tell by a dyno graph. Even comparing a dyno graph I am sure you would see a good sized different in the power curves between your car and a supercharged one. Not to mention the huge differences intercoolers and charge piping can have on the way your car drives as well as ECU tuning. It is something you need to experience driving the different cars, not comparing dyno graphs.

Take a look at this dyno graph of the SM2 RX-7 I mentioned before.

http://www.rx7club.com/attachment.ph...hmentid=105019

This is at 15psi on a mustang dyno letting off at 6500RPM. In races we routinely reach 8700RPM or higher which is about 75MPH in 2nd gear and the top end power is much better now since that dyno was run with a stock sized intercooler and the car has one twice as large. This car sees positive manifold pressure at pretty much any RPM and hits 15 psi at 2000RPM. Compare these numbers to a well tuned GT35R RX-7 which sees 15psi boost by 3400RPM.

Sequential Twin Turbo GT35/40
3500 195 125
4000 210 175
4500 235 220
5000 300 250
5500 320 310
6000 350 350
6500 363 365
7000 000 380
7500 000 380
8000


Big difference in the HP it is making at the low RPMS isnt there? Both cars running 15 psi.

Not to mention both cars will feel totally different driving them because of the ECU tuning and especially the length and size of the intercooler pipes and the size of the intercooler.

In addition I have raced a whipple supercharged car mounted on the intake manifold that made 30 less peak HP than the sequential twin turbo RX-7 but had 300 ft lb of torque all the way up almost from idle and similar in weight to the RX-7 and I will take that over the power delivery of the RX-7 on a technical track.

cretinx

I'm not going to quote everything in the post above me - but let me restate -

I have driven turbo and supercharged cars since I had my license. I recently swapped cars with my friend's supercharged Miata, so I have the feel of a supercharger fresh in my mind. The RX-8 with a GReddy turbo FEELS like it has a supercharger on it, not a turbo

By this, I mean that

A) there is practically no delay for power delivery

B) power comes on early, and stays peak FOREVER - the dyno of my car showed the torque delivery in an absolutely flat line, as a typical roots type supercharger will do (the centrifugal types amplify the engine curve, building boost as revs increase - it did not feel like a centrifugal - it feels like a roots/eaton style with max torque ALL THE TIME)

C) the car doesn't run crazy at the top end - normally in my other turbo cars the power would be lackluster, and then just come and come and come - on my RX-7 both torque and HP increased until redline - it doesn't feel like that on my 8 - it feels more like a naturally aspirated high displacement 6 cylinder - like a Z - power hits early and there's no more weird pulls - the torque is constant

D) transient boost response is incredible - this turbo is VERY small for this car - rotaries generate 3 times as much heat as a comparable piston engine, and this spools turbos up way faster on the rotary - hence why the turbo and rotary are inseparable - due to this fact, you can mash it in 6th gear on the highway and just FLY - just like a roots style supercharger. If this car had a GT3540R on it, it would be insane - you wouldn't be able to get any traction due to the twin-scroll ball bearing setup - with the 18g in a TD06 housing, its just right.

If you were running a larger turbo, perhaps you'd have the typical problems of a turbo car, but GReddy got it right - the car feels stock - it feels like it came from the factory this way - I am so impressed I can't really find words. This is definately the best turbo setup I've ever felt, and I know it can make TONS more power.

The problem with a supercharger is running more and more boost - a common supercharger will run 6-8 psi and call it quits because most people aren't going to attach a smaller pulley to run higher boost than that (MOST people) - the benefit of the turbocharger is you can simply increase the boost and add fuel, making power easier to come by without swapping out pulleys. This car's characteristics - high revving, small displacement, lightweight, lots of heat, rear wheel drive - they all make it seem like it was meant to be turbocharged from the get go.

When someone shows me a supercharger that is kicking the crap out of a turbocharged RX-8, then I'll silence myself. In fact, rumor has it that Mazda's skunkworks are playing with a supercharged RX-8 - its really beautiful with a nice big hood scoop - if the MazdaSpeed 8 comes out supercharged and kicks butt, so be it - me, I've always gone turbo and I always will, just look at my rides to know what I'm about.

rotarygod

Got some problems with these statements.

1: First of all, turbochargers also have parasitic loss. It's not only a supercharger
phenomenon.

2: Which are not as efficient as a turbo? Which turbo? All of them? Different types of superchargers have different efficiency ratings. Roots are terribly inefficient, twin screw are not. Efficent in what way though? Heat? Amount of power needed to turn the supercharger? These too can vary greatly between different styles. Remember that a turbo is a large restriction in the exhaust system. Put a 1" tailpipe on the car and see how fast it is. You need a little boost just to get you back to where you started. Yes a supercharger does too. Both have losses. don't make it seem like turbos are free power. Far from it. I could go on and on about this.

3:Last statement is far too vague to be accurate. I can make that statement right or wrong depending on the scenario.

The fact of the matter is that the only person who can compare the Pettit supercharger prototype to the Greddy turbo kit is the person who has been in both of them. That's it. It really doesn't matter if anyone else has been in turbo and supercahrged vehicles before. If they haven't been in these 2 exact vehicles that are being compared, it is irrelevant information and can not be used as a comparison. It can also not be assumed that one car was not running properly based on the outcome of the review being different than expected. This is pure speculation. What if they were running properly? Got any proof otherwise? It was what it was. Any other possible scenarios that could have happened or what another car should feel like is really nothing more than an excuse. This was the review of the 2 systems that were directly experienced firsthand.

IZoomZoomI

outside of this debate to bring this back on topic... i felt that it was a great comparison, he poster mentioned his opinions and pros and cons of both systems. He mentioned that the greddy turbo had good punch in the beginning and a better high end which sounds pretty accurate and that the s/c had low punch but less high end hp. He didn't favor either in his remarks/opinions about both until the end which he concluded which suit his driving needs the best. The other opinions regarding which is better is a bit lopsided... based on "owners" vs a person that is totally unbias b/c he owns neither.

guitarjunkie28

in anyne's defense, all the motors i've taken apart have looked pretty hammered on the side seals and bearings. i don't think it's from the turbo or any other mods, although they may accelerate wear.

what i'm starting to do is recommend changine the side seals to all my customers when i port/rebuild. it's an extra ~$200, but well worth it in the long run.