Turbo advice

Matt, I opted to move this thread to the RX-8 catagory because although it is definitely "technical", it is very RX-8 specific. Just thought it would help boost other categories too. Technically, everything about our cars could go in the Technical category if we don't watch. Then we'd have one jumbled area!

Anyway, here's my short and sweet about turbo RX-8's. I'm positive you don't want to do it before your warranty is up! Since you're an '04 like me I'm guessing that's the case. I haven't read too many successful stories about turbo's and managing the computer correctly on our cars. The one successful company I personally know of makes a supercharger, not a turbo. That's Pettit Racing in Florida. Costs seem to run above 5k for stage #1 and above 10k for stage #2 (last time I checked).

That's enough of a deterant for me! If you want to read TONS more about turbo'ing your RX-8, there is a month's worth of reading on www.rx8club.com. But be warned, that forum is full of young hotheads that want to rule the world, read as much as possible over there before you ask a question that could appear to be from a newbie!

I think your best bet would be to get a turbo kit, such as Greddy or Esmeril. They generally come with all the parts and the hard part will be the technical, not the assembly. I agree with John about reading up on rx8club.com as there is a lot of information there. Anything by MazdaManiac is good as he appears to be the master of the RX8 turbo.

I have a friend here who has done an engine swap and knows about turboing, even though it was a SR20 engine, not rotary goodness. If you do go turbo I would definitely do your research and make sure you have enough in reserve to replace engine parts in case you mess up.

If you use it as your daily driver, it's highly recommended to supercharge as boost is linear, tuning is easier, and things are generally more reliable.  Also the torque curve on the supercharger kit is almost flat which means it will be easier to drive, less peaky (boost won't kick or surge), and you get the sexy whine.  I'd also recommend stock-piling parts and pre-installing things like an upgraded clutch, new pads (Bendix CT-3 if available, excellent modulation, not too much initial bite, little to no dust OR more aggressive for the track but you sacrifice smooth stops and rotor lifespan), upgraded/wider/summer tires, sway bars, springs, shocks, mounts, bushings....

Basically all kits will add power, but you want to be able to contain the power before you start adding it, also if you build your car up to handle power FIRST, you can add more later and still be able to handle it, unlike the weirdos with 350hp Cobalts that torque steer across lanes. 

After you have all your necessary upgrades I'd look at what shops you trust and what tuning they will support as this will truly decide what kit you choose.  No use turboing your car if the shop that can tune it is far away. 

Also a note, Car and Driver entered a contest to mod an RSX and won the track event with the lowest HP rating and the only supercharged car.  It's a fun read. 

the winning car had the second-lowest horsepower (233 at the wheels; the lowest was 226, the highest 503) yet had gone through the autocross course quickest (1:27.32 seconds) and had turned the fastest quarter-mile time (13.5 seconds at 105 mph). It had also won the braking contest and was considered the most beautiful at one of the car shows.

Thanks for all the input, im not looking at doing it until my warranty is out which should be around this christmas at the earliest so it will be pretty soon.  I try to do things right so i started upgrading the suspension quite awhile ago.  I have springs and shocks on the car, i have sways just not put them on yet, i need to get better tower bars for the car.  Im going to get awesome pads as soon as i actually need them.  The clutch is a stage 2 that was put in by the previous owner but i plan on changing that when i get FI system.  As far as the RX8 forum, i read on there everyday to learn more about my car but the problem is that there are a lot of guys who think they know but really dont and they give out bad information but good info comes from MazdaManiac and Teknics for example.  I would really love to go with the petite racing supercharger just because its simple in design and as far as the power throughout the RPM range it looks super smooth yet pretty big power increase, if i got that i would totally want the company to put it on and tune my car (hich they do for an extra $995) since they designed the system and know exactly how it is supposed to act.  I was really looking to see if anyone in or around lynchburg did turbo tuning for the RX8, i have not found anyone yet so i was just wondering if someone around here did that kind of work on our cars.

I feel its necessary for me to chime in since I had a turbo '04 RX8.

Quite honestly, its not worth turboing the 8 with the renesis. I know some guys are making more power and claiming reliability, but in all reality, these kits have only been on the market a few years. The GReddy kit ships (at least it did in '04) with an e-manage that has got to have one of the worst tunes I've ever seen from a mfg.

I ended using an interceptor-x (no longer available to my knowledge) which is essentially a hacked microtech that piggy backs to the stock ECU. The only thing you lost was traction control, which with the turbo - was useless anyway :)

The GReddy kit was not well designed for the RX8s high RPM powerband. I know there have been guys who have upgraded the turbos and made a decent amount more power, but at the end of the day, you've spent close to $10k building a 300whp at best platform.

You could buy an rolling chassis FC, build, tune and enjoy for much less than that $10k or at worse - the same and have 350 to 400whp and by more reliable.

The side seals on the renesis just cant take abuse.

I know it sounds like I'm being negative, but I'm really not trying to. I loved the turbo 8. It was a blast to drive, but a bitch to tune. After it all, the motor lost compression after 40K miles or so. I can only hope the newer kits now are better prepared.

I think the 8 is a great NA platform and if you really want to boost it, look into swapping in an older 13B REW or 20B.

If you have specific questions about turboing the 8, the greddy kit, etc, just let me know. I spent a ton of time in the garage with mine :)

na i totally value and respect your opinion and advice especially since you have had a turbo RX8.  As far as the Greddy system goes they now ship with the E manage Ultimate which in theory was supposed to fix the tunning issues of the the older Blue E manage, wheather that happened not completely sure at the moment.  I wouldnt mind having like an older model RX7 and really putting the power and money into it but i do need something that is semi practical right now ( 4 seats and a little trunk space).  I have a friend that is selling a 94 FD in fairly decent condition for 8 grand which i would buy if i had mine 100% paid off but i have a little less than a year left to pay so i cant get that right now.  I was just looking to get enough extra power to do a little playing around which is why i was kinda looking into the Greddy Kit because from my understanding its a complete kit and comes with all you need aside from a boost gauge and controller, but before i would get it i want there to be someone near me that could plug in and tune it if it was needed.  With the E Manage Ultimate that they currently ship, in theory there should not be any major tuning necessary but i dont want to purchase the kit get it on and then it need some tunning but not have anyone around to tune it.  I was considering getting the Cobb AP if i get the greddy kit that way Jeff could tune for me, it would take a little longer than having someone i could drive to but it would get the same results.

just out of curiosity the 13B REW what is that out of?? an RX7??  and the 20B is the 3 rotor correct? Would the 20B even fit into an RX8?

The 20B will fit fine into the RX8 and there are actually a group of people on RX8club.com that have done it. I think eventually that will be the route I will go, only I'll get a second car to do that with or I'll get a second car as a daily driver, which won't be for awhile. Trouble with the 20B is I don't know if there are parts readily available.

In reality I hear the Greddy kit is awful because of the lack of power, unless you get the stage 2 I think. Either that or there is a certain Greddy kit that is awful and I think it mainly deals with the turbo sucking and dying after awhile. I'm fairly new to turboing but as I said I have a friend that knows a lot with piston engines and has a turbo. he installed himself.

Well personally i have really put a lot of thought into the 20B engine.  From what i understand and what i have gathered through various sources is that the 20B engine its self is around 7,000 plus about 1200 for someone to put it in so for about 8200 you could get the 20B installed which will ( from what i understand ) give you more power than the esmeril turbo system and the Petite racing supercharger.  so for around the same amount of money you get more power and you get something that will not blow your engine up.  So i have thought quite a bit about going that route but i have not found a place to buy a 20B and have not found anyone in my area that knows how to install.  If i could find a place to purchase the engine and someone close by to install then i would for sure go that route as soon as i pay my car off.

Here's a link you may enjoy Matt. Atkins Rotary ... This is where I bought my new motor for my RX-7. Looks like they got in a shipment of JDM motors recently.

I found some 20B engines for 4000. I don't know where you are looking. I basically came to the conclusion that it costs the same for a turbo or a 20B swap initially, but I think in the end, depending on the turbo you buy, the 20B swap is more expensive. True there are turbos out there that can get more expensive, it just depends on what you want to do.

Plus if you get the 20B you start NA with the same power as a turbo'd 13B. You can always add a turbo/supercharger and get even more power. I was planning on do this someday, but again, not sure it will be on my new 09. I might buy an older RX8 or possibly another car to do the swap.

Let me jump back in...

Your are correct in that the REW is from a '92 to '02 FD (3rd gen RX7). They run about $2k for a JDM motor.

The 20B is most commonly found in twin sequential form - like the REW only it has smaller turbos and most guys opt to use REW turbos instead (especially '99 and up). These motors run close to $4000 in used condition.

The catch with any swap really - is you're going to deal with a used motor. I've had plenty of experience with these, and not one has been positive. In many rotary circles, you'll find that the general consensus is to buy a JDM engine for the core and rebuild it. Sure, you may get a running one, but its probably not going to last. Not to mention, many of these blocks sit at a port, a can then another port for MONTHS before reaching us here. Plenty of time for carbon lock, rubber seals drying out, etc.

That being said, the cost of 20B swap is arguable I suppose... if somebody will install it for 1200, I can only assume thats labor/shop fee. Its going to require custom mounts, harnesses, etc to actually make it work.

A big issue with the 8 is doing the swap and keeping the existing cpu brain happy with the other functions in the car such as the traction control, instrument panel, etc. I mean, with 7s, we dont have electric throttle bodies, but you do with the 8 and thats just another wrench in the works you have to think about when doing these swaps.

I solid, shop installed, 100% factory feeling 13B REW swap from what I've heard is running guys between 10 and 15 grand. You should factor in at least another 2 to 8 grand for a 20B.

IMHO if your going to do a swap though, the 20B is well worth it. In the land of rotary - you can't beat that torque curve of a triple rotor :)

I hope to have a 20B in my FC someday... for now the 13BRE (2 rotor version of 20B) will do just fine...

EDIT: (I just looked at the posts above and this has been stated. I guess this is just my view on it and further statement that a S/C may be the way to go)

I've been looking around and a supercharger might also be a route you want to go. It requires less tuning and is, IMO, a more stable solution. My friend has a turbo and he is constantly working on the car. He describes it as a project you can never finish. When you get it close to 90% something happens and you have to redo and you end up spending more time in the engine bay. His car is in a constant state of not running or in varies parts around his garage.

With a supercharger it is a little less work, you bolt on, tune, and you are 95%. Sure some small things could come up and you can tweak it. You are limited in the amount of power you can get out a Supercharger and for RX8s the kits are pretty expensive compared to turbos. Again I think the reliability factor comes into play there. Then there is the other things you have to do to use the power generated.

With any type of performance upgrade you could have hidden costs or costs you don't think about, like mentioned earlier. If you are shooting for more than 300whp you might want to consider a clutch upgrade, drivetrain improvements, and you will definitely need aftermarket exhaust with any type of forced induction. Those cost money and are not often included in the price of a solution.

An example is the Greddy turbo kit, which is about $4000 for the engine parts. You'll spend more on the exhaust upgrade, if you haven't already, plus a clutch, all your gauges and sensors. It can add up.

I myself have seriously been thinking about a Hymee or Pettit S/C with Nitrous eventually. Of course that is a long way down the road since I still have a warranty and a brand new car. I'm also not looking for something to use on the track since there aren't many around longer than 1/8th mile.

If i could find a place to purchase the engine and someone close by to install then i would for sure go that route as soon as i pay my car off.

-mat04rx8

Maybe it can be a group effort. I know I've learned a lot just being around my friend with the turbo. I'm sure he'd like to get his hands dirty as well, even though that is a drive.

http://www.axialflow.com/index.htm

They make a different type of supercharger and are testing for an rx8, maybe you can help them with a test car :-)

Are they looking for testers? I saw that a long time ago but I thought development had been ongoing for a while now.

A note about testing. I was trying to get a Cobb AccessPort for testing but I could never get a response from the dealership about downloading their ROMS. :-(

Wow i didnt expect such response from you guys, its awesome to get some really good feed backs from you guys.  I have looked at the pettit racing supercharger as a very possible thing.  I mainly want that because of the reliability factor and because i can have it installed and tuned by the guys who developed it so they know exactly how to do it.  I know all about the hidden costs and upgrades to suspension, transmission, clutch, etc.  I have already began these upgrades in preperation for a little more power.   I dont want to have to much power just enough to make the car feel like it should have when it was first made, mazda totally should have givin this car a little more power.  All in all though i think when i pay my car off i am going to go for the supercharger route.  I may look into axial flow and their development but right now pettit racing is my choice.

I got even more info from our meet from the Master tech @ LM!!!

The 09 and ups have an additional 2 oil injectors, the motor running them is now electric.  What this allows is upon engine shutdown, the fuel injectors are halted and the oil injectors are maxed to spray oil in all the seals, keeping them lubricated and soft for the next startup.  I believe they also do a bit more magic at start-up but he didn't elaborate on the point.  Also the Star Spec Mazda tech said the 09s are much more balanced from Mazda and run a lot smoother.  The tech @ LM also was more than happy to help with labor discounts if you wanted one installed... he seemed as curious as we all did and the #2 tech works at a shop extremely capable of doing the before dyno, the tune, and the after dyno.  Pierce has the race shop's info. 

wow thats awesome.  He said he was more than happy to help with discounts on installing an 09 engine, or what??  Either way that is awesome!!!  You said that the #2 tech works at a shop that does dyno, and tunning??  I really need to know where that shop is and the name of it and the guy you spoke with because i have not been able to find anyone that can do that type stuff around here.  Please give me that info.  All good stuff though.