I'll introduc myself as this is my first post. I "inherited" the RX8 from my dad who put a lot of time & effort into the car and did not want to get rid of it. He has the Mazdaspeed flywheel, SR motorsports full exhaust (header back + HF cat) and a few other cosmetic things.

I just sold my E46 M3 so coming from that I've always complained about the 8 being pathetically slow.

Well, a turbo will/should fix that. I've searched through the forum and read about people with the greddy kit getting 220-230 HP at the wheels in stock form.

I've also seen those running with 7psi boost and running closer to 270 at the wheels.

I spoke with Pettit Racing today and they would install the greddy kit for 1200. Thats install & tune. I asked Cameron there what he thought of running 7psi or so and he replied "if you dont mind blowing the motor"

From what I've read here to run the 7 psi the person tuning it must have a good knowledge of the emanage software, and also bigger injectors must be purchased.

Now, Im gonna go one more step and ask if there is anything known that can be done to the Renesis to make it more "turbo friendly" much like lower comp pistons and rods would be in a normal motor.

Im not sure if I can make the car as fast as my M3 was, but I'd like to try.

Im ready to buy the kit today but I want to do more reasearch so that I can make a correct choice the first time.

Im curious what owners of the turbo kits think. Did you notice a huge improvement? How long have you been running with boost and do you feel that it was worth it?

Thanks for any information. I will greatly appreciate any input.

 

Well.... I'm not yet a FI owner, but I will be soon. In the meantime, I am learning as much as I can.

I don't know what "Cameron" is talking about. There are lots of people running 7psi with the GReddy. Some have run 9psi. Still others are getting more mass flowrate using other turbos. Of course, you could blow it on 5 psi if you aren't carful about detonation. You need to monitor AFR at a minimum. Intercooling and colder plugs will also help reduce the chances of detonation.

From my research here is what you can do to get ready:
1) buy Corky Bell's book "Maximum Boost". This is a must if you plan on understanding and managing your FI car.
2) install colder plugs - at least in the leading position.
3) get RID of your aftermarket exhaust. Folks have had issues with AFR and backfiring with aftermarket exhausts.
4) get an LM-1 WB02 installed.

 

Greddy's turbo's pretty small,,
7 psi from it won't blow your engine if properly tuned.
Also, stock injectors are good enough if you plan on staying at 7psi on Greddy kit.
I would think pettite would be knowledgeble???
I guess not..or its just that "Cameron" person lol

 

In an earlier thread the people at Pettit said that after they took a look at a turboed engine, there was a lot of wear and tear. I think they are reputable, so I'd believe them, but the fact is that out of all the people who now have turbo'd 8's, I've only heard of one person blowing the engine, and that seemed to be a tuning issue, not the unit itself. I think the GReddy is a good mod, but if you are looking for big numbers, it may not be the unit for you. It will probably take you to the high...possibly mid 13s, but thats about it. But its up to you...I'll continue waiting!

 

Well my ideal thing would be a 3 rotor. But the only place I've heard of that does this is Acosta, and I've heard millions of horror stories about them.

If they could do the 3 rotor for 5-6k that would be ideal.

But anyway, Im not being unreasonable in my goals with the RX8. I just want some more pep.

Thanks for the info guys, Im really appreciating it.

Keep it coming.

 

The Greddy kit runs 7psi originally from Greddy. I don't know what Pettit is talking about. With this 7psi and proper tuning you will be between 220 and 240hp. I definitely love the turbo and would definitely buy it again. 7psi boost is not alot for an engine. If the Renesis can't take that, than in my opinion its a poorly engineered, shitty engine, as pretty much any piston driven engine would have no problem with 7psi. I think/hope it will do fine though. My only complaint with the Greddy turbo is the piggyback setup, but hopefully RotaryGod will have that solved with a month or two with his Megasquirt setup.

 

7-8 psi will give you about 250-260 whp. I have 7.5 psi on my car right now & it runs like a champ. No need for boost controller or larger injectors. If you are going past 8 psi, then that stuff becomes necessary. Greddy Emanage though is pretty much necessary to tune & lean out this unit.

In terms of reducing the chance for detonation a good set of colder plugs, tuning, Racing Beat's Oil Metering Modification, etc.

It's not the aftermarket exhaust that people are having problems with (backfiring), it's the hi-flow cats. Might want to have your stock cat. around just in case.

One thing I think you would really like about the Greddy is that since it is a smaller turbo, boost/tq. comes on at around 2800 RPM. Get more push from the low/midrange. Having driven the M3 numerous times, you have a very flexible tq. range. With this turbo it acts almost like a roots/screw-type supercharger in that tq is across the board, not just on the highend. Peak hp might not be as great, but it makes good everyday hp.

Another thing is if you are looking at a $5-$6K budget that won't get you into the upcoming t3/T4/T4 systems. After all is said & done with the Greddy (about $2900-$2950 street price), BOV, Gauges, etc. you are looking at about $4500-$5000. When all is said & done you are looking at about 240-260 whp (with limited potential for more). With the other kits you are looking at closer to $9,000+ ($7,500 for the full kit, $1,000 for install, $500 for random stuff). End with around 280 whp, with potential to go upwards, but nobody is sure how high.

I've had mine on for about 3,000 miles. Had my hiccups (came from the factory running 4 psi of boost across the board, boost leaks, etc). Now that I have the thing tuned I love it.

Pettit is a good outfit. They do have their own supercharger system coming out. Not sure if that is why they are holding off. They did recently do a 3 rotor RX7 (i think it was in Turbo). If a 3 rotor was ONLY $6K, I think you would have a lot of people doing it. A 3 rotor conversion is easily 2X that price.

 

If you could have a 20b swap for 5-6k, I think A LOT of people, including myself would already have this.

 

Very helpful and informative. Thanks a lot. I think I'll be good for a while with the 7 psi setup and its good to know I wont need the injectors or boost controller. Maybe later when I want more power we'll see what I do about that.

I guess I can start ordering stuff soon. One other thing that worries me is where the heck to put the gauges. I have the NAV so the super nice oem looking 3 gauge pod that fits in the center wont work, so I think I'll put 2 gauges next to either side of the steering wheel and that should be enough for gauges.

I figure boost, and oil temp gauge (temp so I know when the motor is warmed up & ready to rock) Is the AF gauge needed? Wont that be pre-set when they tune the car?

 

3 rotor for $5K-$6K......................
Sorry but is MUCH more .

I maked 273 HP with the 5 psi greddy kit set up.......
you can make the 270 HP at 7 psi.............

Manuel

 

sorry if you are going to petit why not get their supercharger?