I totaly missed this thread when it was "going on" (http://www.rx8club.com/showthread.php?t=35946&page=8&pp=15&highlight=pettit) but I did find the last paragraph of the Motortrend review interesting.

"Although Pettit’s wares add to the car’s edge and shave a few tenths, the drop in drivability, a slower slalom speed, and no return on the brake-kit investment indicate that when the cars perform as well from the factory as the RX-8 does, maybe “good enough” should be left alone."

Motortrend Nov 2004



Of course RX Tuner's artilce was interesting too ..

"The kit takes the great handling, but underpowered RX-8 into a whole new terriroty."

RX Tuner Volume 1, Issue 7 (why isn't there a month on this?)

How did it affect slalom speeds? I can understand a drop in "drivability" but slower slalom? How much does this thing weigh?

Here's the article. Mayby that will help the question.

http://www.rx8club.com/attachment.php?attachmentid=30027

when we saw the car at 7stock, they had removed the front strut tower bar..
in the picture there, it's missing as well..

i wonder if they just run w/o it?

that'd certainly cause a drop in slalom performance

when we saw the car at 7stock, they had removed the front strut tower bar..
in the picture there, it's missing as well..

i wonder if they just run w/o it?

that'd certainly cause a drop in slalom performance


they can't be that retarded......

I'd have to say, if the numbers in the article are accurate, I don't know that I could justify the cost of the SC. Although shaving 4/10 off a quarter mile is pretty good, if you lose a lot in drivability, it's just not worth it IMO.

They lost drivability from the suspension upgrades they did. This is another shining example of how bigger isn't always better. In this case it was the sway bars, making the car too oversteer happy. Their big brake kit actually hurt stopping power. Just because something is bigger doesn't mean it will work better. It may sound good on paper, but if you mess up the balance of the car, it will only hurt you every time.

The article mentions 2 different supercharger kits, a high and a low boost kit. This is a joke. Low boost is 4 psi but high boost is only 8 psi. To me, 8 psi IS low. High boost would be 15+. $3800 for 4 psi or $5000 for 8 psi.

I and many others saw this car at Sevenstock. The craftsmanship wasn't very good. Hopefully this will all be worked out by production time. Their aluminum upper manifold was absolutely horrid. It needs to be totally redesigned. It may be temporary but why is there never enough time to do it right but always enough time to do it again? Build the first one properly and keep it. This is faster and easier. They didn't want anyone taking pictures under the engine cover while it was off. While I din't take pictures with it off, I did take up close pictures looking under it. They weren't there to stop me. There was nothing special. The supercharger is too small. For 4-8 psi it is alright but it isn't going to give them any more power if they want it.

The reason their car doesn't idle very well is obvious. The intake pipe before the maf is too long. Even the K&N pipes that everyone installs on their cars is too long here. If they were cut down just a small amount, they would idle better. In Pettit's case, they should have moved the maf to closer to the air filter. Their filter was in the front of the car so the maf in this location wouldn't be a good thing. However, they could leave the air filter in the stock location if they tried and kept the maf inside the engine bay.

I applaud them for working on a kit. However, if they want to be taken seriously, they shouldn't let something be tested that isn't complete yet. They also shouldn't let the public see poor craftsmanship. The idea is good but the execution is poor. Maybe with alot more refinement they can turn that kit into something worth getting excited over. Keep an eye out for Hymee's twin screw kit. I assure you that he won't half ass any part of it. Not even the first one.

Thanks for posting the article. Pretty much sums up how I feel about the aftermarket efforts in general. It's not just the Pettit RX-8, I've seen many other tuner applications on other high performance cars that resulted in a marginal gains in some areas, while degrading performace in other areas.

I'm sure the end result was poor because they rushed it to market. Next iteration will probably be better.

What I find even more interesting is that Pettit used a twin screw supercharger, just as Hymee is planning. In theory then, won't the performance gains be similar? Or do you think that the gains were lower than expected (50 HP at 8 Lbs? Bleh!) because they did a rushed job on the tuning, too? And anyone have any idea of what engine management they used?

i think, but correct me please if im wrong, that petit used a smaller version of the one Hymee has chosen. i dont remeber looking for engine management at 7stock. could ask steve kan as i believe he took a ride in it(might have actually driven it). or ryan for that matter.

i think, but correct me please if im wrong, that petit used a smaller version of the one Hymee has chosen. i dont remeber looking for engine management at 7stock. could ask steve kan as i believe he took a ride in it(might have actually driven it). or ryan for that matter.

I didnt see any engine management in there.. let me look at my pictures though..

EDIT: there's no VISIBLE sign of any engine management system beyond the standard ECU in my pics.

who makes that front bumper on the petit SC 8?

The port & polish option is looking better and better all the time! No obvious signs of tampering, less weight, fewer moving parts, and increased durability instead of reduced.

I think our impatience may be causing aftermarket companies to rush performance as fast as possible. However, companies like Pettit, Racing Beat, HKS, etc., are only trying to cash in on the RX-8's success. I can't blame them. I'll wait a few years for the aftermarket to open up more. Until then, it's back to the drawing board.

Racing Beat is doing it right. They take their time and develop their products after extensive testing. If you notice, Racing Beat has never offered as many parts for the cars as other companies do. They have a very limited product base but intend to do that segment the best they can. They will be the first to admit if you want more power or more extreme mods that they aren't the best ones to talk to. You won't go wrong with Racing Beat.

RG, care to comment on my questions above?

If you are referring to the Pettit kit not being built so good I would agree. Cam admitted that the production version will offer an air/air intercooler instead of the air/water unit we saw. The aluminum upper manifold will be completely different from that one. The intake pipe was way too long in front of the maf which caused it to idle rough. Almost everything about their kit had problems. However, almost everything about their kit will be redesigned for the final product. I'm sure that the quality level will be much higher in the end. I'm pretty harsh on them but that's only because the product that I saw for myself wasn't very nicely done. If the finished product is nice, I'll like it.

As far as what ecu they are using, I have no idea. My guess would be something like the eManage. I know it isn't stock though. When the product hits the market, they'll tell us what it is.

Racing Beat is doing it right. They take their time and develop their products after extensive testing. If you notice, Racing Beat has never offered as many parts for the cars as other companies do. They have a very limited product base but intend to do that segment the best they can. They will be the first to admit if you want more power or more extreme mods that they aren't the best ones to talk to. You won't go wrong with Racing Beat.

Agreed 100%!

It was this way with the FD stuff they sold as well.

If you are referring to the Pettit kit not being built so good I would agree. Cam admitted that the production version will offer an air/air intercooler instead of the air/water unit we saw. The aluminum upper manifold will be completely different from that one. The intake pipe was way too long in front of the maf which caused it to idle rough. Almost everything about their kit had problems. However, almost everything about their kit will be redesigned for the final product. I'm sure that the quality level will be much higher in the end. I'm pretty harsh on them but that's only because the product that I saw for myself wasn't very nicely done. If the finished product is nice, I'll like it.

As far as what ecu they are using, I have no idea. My guess would be something like the eManage. I know it isn't stock though. When the product hits the market, they'll tell us what it is.Actually, I was wondering why they were only getting a 50 HP gain with 8 Lbs of boost. Others have used that and the gains are more like 80-120 WHP. That low of a gain makes me wonder if they kludged the engine management just like they did the rest of the kit, so they could get it ready in time for SS7.

But if we are talking about a 50hp gain to the wheels, that is a pretty big increase. More than 25%.

But if we are talking about a 50hp gain to the wheels, that is a pretty big increase. More than 25%.

Picking up a 1/2 second in the quarter for thousands of dollars is pretty lame no matter how you look at it. If I wanted a car that would only break even with it's nearest (stock) competitor when supercharged, I'd get a Mustang. ;)

Are rotary engines different in the way they gain power with boost? 8 psi is over a 50% increase in atmospheric pressure- that's some pretty heavy loss if they're only seeing a 60hp gain.

Picking up a 1/2 second in the quarter for thousands of dollars is pretty lame no matter how you look at it. If I wanted a car that would only break even with it's nearest (stock) competitor when supercharged, I'd get a Mustang. ;)

Exactly.. I am pretty disappointed in the performance gains... Guess I am back to waiting for another system to display it's true potential...

Hopefully SFR will publish it's findings within the coming weeks as they said they would...

Picking up a 1/2 second in the quarter for thousands of dollars is pretty lame no matter how you look at it. If I wanted a car that would only break even with it's nearest (stock) competitor when supercharged, I'd get a Mustang. ;)

I don't disagree with this. Frankly, I thought a 50 hp gain would have shown slightly better numbers in the quarter than it did.

Like I said in my first post, it doesn't look like this SC is worth it.

Well, if the engine management is so poorly tuned that the car bogs and hesitates on every shift, you lose the time you picked up during acceleration. Just because they can show a gain in horsepower on a single gear dyno pull doesn't mean that the 0-60 times will be better at all. Peak power is just that, and if there's less space under the curve, as well as erratic behavior on the 1-2 shift, it could be slower than stock.

Aftermarket FI is a complete package, I wish everyone would focus less on "how many lbs. of boost" or "Dyno HP". It means nothing.

Good point!

Well, if the engine management is so poorly tuned that the car bogs and hesitates on every shift, you lose the time you picked up during acceleration. Just because they can show a gain in horsepower on a single gear dyno pull doesn't mean that the 0-60 times will be better at all. Peak power is just that, and if there's less space under the curve, as well as erratic behavior on the 1-2 shift, it could be slower than stock.

Aftermarket FI is a complete package, I wish everyone would focus less on "how many lbs. of boost" or "Dyno HP". It means nothing.EXACTLY!!!

I believe they are using the Rick Shaw piggyback. The other thing is, the car is bogging during gear shifts, that tells me the quarter should be quicker when they wring that out. I just got all the kinks worked out of my CZ unit, and actually picked up .15 by fixing the bog during a shift. IT will probably be higher on a FI car.

I expect the car will get faster. My impression from seeing the car at 7stock was that they were really just trying to get the car together for the show so that they could show everyone that they had FI for the 8.

Oh yah, if they are using the emanage (which I don't think they are), Greddy just released a patch for it for the RX8!!!. It now supports their hotwire MAF and ingition timing. I haven't played with it much, but looks like it could solve some problems. IT will be interesting to see how much Greddy is dealing with the MAF when they finally release their kit.

Slavearm

(Uh sorry about going off on many tangents there).

Not at all, good information on the emanage changes...

Oh yah, if they are using the emanage (which I don't think they are), Greddy just released a patch for it for the RX8!!!. It now supports their hotwire MAF and ingition timing.

If that's true, that will help alot.

Like EVERYONE else they too are having problems tuning the RX-8 ;)

To quote the article "Pettit assures that it's new ECU programming should remedy the problems"

So ya...the ECU is a beast NO ONE has yet tamed :)

Does Mazda help aftermarket companies at all with the ECU, or does everybody have to reverse engineer the code? I'd think it'd help Mazda if they were open about the ECU programming. It's not like Chevy is going to come out with a rotory competitor tomorrow just because Mazda makes the ECU code public domain. The benefit would be you're selling a performance car with as many quality power adders out there as a 5.0 Mustang.

i think, but correct me please if im wrong, that petit used a smaller version of the one Hymee has chosen.

That is correct from the information I have. That blower is rated in the 300 odd HP range. The one I am using is rated in the 400 odd HP range. They are both Autorotors. From what I can see in the pics, we will be mounting / packaging ours considerably differently.

The fact that they gained 4 MPH is a good indication of the extra power this unit is putting out.

I went to the drags with a mate who is testing a new PD blower (Eaton roots). He made something like 375 HP at the wheels on his blown LS1 Monaro (Aussie spec Pontiac GTO). His E/T didn't go down much, as he now has problems with traction, but his MPH was up by about 5.

Can't wait until I here the blower whine and rotary combo for the first time.

Cheers,
Hymee.

I am slightly intrigued by the idea of FI but with the success I have had with nitrous I still cannot justify the hassle of any form of FI. Nitrous is cheaper to install and run, has no adverse effects on the handling balance, and only stresses the engine when you want it to. Plus, it leads to a less complicated install. Perhaps when boost levels are such that an additional 100 h.p. is available, I'll reconsider the FI.

Charles

Are rotary engines different in the way they gain power with boost? 8 psi is over a 50% increase in atmospheric pressure- that's some pretty heavy loss if they're only seeing a 60hp gain.

not quite it. that is manifold pressure increase (some of which comes from heating the air while it's compressed at less than 100% efficiency), which doesn't have a lot of bearing on true increase in the mass of air being inducted into the engine. it's not loss, it's straight inefficiency with the compressor type and system design.

I am slightly intrigued by the idea of FI but with the success I have had with nitrous I still cannot justify the hassle of any form of FI. Nitrous is cheaper to install and run, has no adverse effects on the handling balance, and only stresses the engine when you want it to. Plus, it leads to a less complicated install. Perhaps when boost levels are such that an additional 100 h.p. is available, I'll reconsider the FI.

Charles

i think what everyone is missing here is that a turbo or supercharger isnt' something you just add to your motor, it is completely changing in a whole way the dynamics of the machine. firing compressed N2O into your intake charge is a "power adder". "bolt on modifications" :rolleyes: are intended to perform the same functions as the stock units, but more efficiently leaving more mechanical energy to move the car forward (doesn't actually work very well with this car, obviously).

a supercharging system, with either a blower or a turbo or whatever you choose to use, changes the whole dynamic. all the pretty sucky turbo kits we've seen so far act like they're something you harness the engine with. this pettit motor has also obviously been horribly executed, and it's like they did as little to change the motor as they could (instead of changing it as much as they could concieve of). it's entirely the wrong way to go about building a car like this.

if they're going to go to such an extent, why isn't anyone taking their motor apart yet, being that they're already happy to invalidate their warranty??

If I am allowed to answer your question, Wakeech, I would say that the reason most of us do not want to disassemble our engines is because we have a firm belief(or maybe mere hope) in the strength of the engine as it is from the factory. Companies who are designing such systems also know that most of us who would purchase off-the-shelf systems are not likely to remove the engine from the bay. We also tend to see other engines with 10:1 compression ratios and turbos running nicely. The key, as you and others have alluded to, is in the tuning. The concept of stuffing more air in the engine is a fairly simple one, mechanically. As you also mention, doing so changes the operating dynamics of the engine itself. So here we all stand with one of the first working examples of FI and now the next step of fine-tuning is just around the corner. If we can wait a few more weeks or months we may also have a working example of FI on a Renesis that runs as well as everyone thinks it should. My own trepidations have been centered around several issues and I tend to think that many of those who are gravitating toward FI are doing so simply out of familiarity. One thing I find curious is that many of those who are the loudest cynics are also those making the greatest demands with the least patience. I guess that's modern american culture.

Charles

sure, tune it all you want but what i'm saying is that if you're dying for ultimate performance, why're you trying to spend too much money to do everything wrong in the first place?

and i agree that this "FI" thing is getting hyped to a stupid amount.

Would you mind taking a moment to define terms and phrases like "ultimate", "too much money", and "everything wrong"?

I have certain measureable goals that I wish to attain in my upgrades and the first tier was to get the RX to be as quick, if not quicker, than the Chevy I used to race. So far, I have cleared the first hurdle much sooner than I thought. The interesting thing, for me, is that the fuel mileage, driveability, reliability, and some other aspects are similar between the two cars.

Charles

If you want a car that drives like normal most of the time but has added power every once in a while, then nitrous is a good, cheap way to do it. There is no complications of installing a supercharger, intercooler, etc.

If you want more power all the time and need to use this power around a track such as a road course or an autocross track, then forced induction may be the way to go. Then you need to narrow down which form of forced induction best suits your goals.

Using nitrous is in no way doing it wrong. Neither is using a turbo or a supercharger. Each has it's own purpose depending on the goals of the owner and how they intened to drive the car. There is a place for everything. In some ways, the original manufacturer could say that anyone not leaving their car alone just as it was built, is doing it wrong.

Charles, if you aren't a road course person and prefer drag racing and straight line acceleration, nitrous is great. Nitrous has the same power potential as any other form of power adder. Again, it's all in the tuning. It doesn't mean that it's intended application is the same though.

if they're going to go to such an extent, why isn't anyone taking their motor apart yet, being that they're already happy to invalidate their warranty??In my case, I simply want to bolt on the most effective power added I can until the warranty runs out. After that, I plan to pull the engine and get it built for "ultimate" performance. Yeah, I know bolting on FI will void a lot of the warranty - but not all of it. And if I do wind up messing things up badly enough to require the engine be pulled/replaced and I have to pay for it, then I guess I'll get to my 4 year plan sooner rather than later. ;)

But as someone pointed out earlier, we're right on the cusp here now folks. Someone (Pettit) has finally come out with a viable FI kit, it just needs to be tuned correctly. I'm sure they'll get it soon. And after that happens, we'll see a whole bunch of kits start hitting the market. And that'll be a good thing. :D

now the question is which one to pick? :rolleyes:

Next year, or when I am next able, I am intending on getting involved in the road course-type events. Perhaps I'll then more appreciate the FI option. It's not that I don't see the benefits of FI, it's just that the early systems are not fully developed enough for me to take that large of a risk. With the help of others on this forum I was able to deduce that the Renesis would handle certain levels of power so I opted for the mystique of nitrous. Plus, it is cheaper overall. I made a few "passes" this past weekend and I am still amazed at how little nitrous is used in the typical weekend of racing. BTW, I got paired up with an '04 GTO. Another one who found out that the new RX-8 is not as slow as they have heard. Three times he found out that he made the wrong purchase.

Charles

hate to sway off topic... what type of times/speed were you getting with the nitrous? I would imagin bein 13's being since the gto is not a slow car...

For the full story read through the two nitrous threads I started a while back. I did some G-Tech runs w/o nitrous and recorded times between 14.2-14.4 at 100+/-mph. With the 55 shot I am recording times around 13.3-13.4 at 109 mph. These seem to be confirmed by the vehicles I have compared my performance against in the "real world". There was a slightly modified '87 Mustang in the mix but I forgot to mention that one because it was over before we hit second gear. To be able to run these kinds of numbers this early is comforting and encouraging to me. Next summer will be even more fun. Thanks for asking.

Charles

Exactly..... I dont quite understand this but one would think that if these companies advertised 10% of what canzoomer did with his mod, they would have a lot of pre-orders by now...

That kind of confuses me.... The only information we have gathered so far is really what consumers have asked of the mfg's....

Dont get that...

now the question is which one to pick? :rolleyes:

I think this is more of a case of a diamond in the rough. Testing is on what is essentially a development mule. More impressive is the fact it even works at all.

Personally, for me, if I want to go faster on a road course, I think the money is better spent in tires and driving lessons. :P

Speedsource seems to be doing just fine without forced induction.

True.. I wonder how much weight savings they had in the car... the Mazda Speed series cars go 0 to 60 in 3 seconds.. but then they weigh less than half of a RX8....