SUPERMAC

Hey just curious as to how much boost the stock engine is good for? i tried looking some info up but couldnt really find all that much.

also on a 2004 6 speed mt what size are the injectors? primary and secondaries?

Im getting ready to strap on my custom turbo kit but i want to make sure ive covered all the basis first. im only going to be pushing out 4 psi, but i havent done any fuel mods or installed any piggy backs yet.

I need to be sure that there wont be any issues before i go ahead and intall this thing.

Thanks,
Chris

expo1

https://www.rx8club.com/showthread.php?t=53406 has the answers to the Injector question. As for your boost question there are too many factors involved to give an answer. You will have to find that out what level of boost works best for your setup. Good luck.

SUPERMAC

well i guess my main concern is just how much boost the motor can hold based on the factory setup. i dont have any fuel mods or anything like that. so im just wondering what i can safely run though it. my turbo setup will be a T3/t4 .57 trim turbo with a 38mm external gate and a open atmosphere bov. custom pipes (much like the ptp kit) and the gate dumps back into the exhaust. i will soon have no cat and a straight though 3" exhaust all the way back.

thanks

zoom44

4psi? you have no worries at all. plenty of fuel stock. you could upgrade to teh the bigger ones from the AT(see that thread linked above) for added safety but realistically you shouldnt need to. lots of folks pushing close to or at 10 now. so dont worry abotu strength of the motor. worry about getting the tuning right. see my sig

SUPERMAC

ok cool. so realistically how well do you think they car will take to me adding the turbo kit and only running low boost? i know tuning is an important part. but just so i know what to expect before i get it tuned. if i go install the kit do you think the car should run ok? or will i have issues right from the get go. also will i get that annoying stall out problem where the car dyes whenever i try to clutch and slow down? cause that crap is way annoying and ive had issues with that from previous cars.

thanks,
chris

Red Devil

What engine management are you using for this 4psi? If you're planning on running that without any type of engine management, I think that would be a mistake (I can't tell if that's what you're saying, or not).

zoom44

well i guess the question is why did those other cars stall? alot would depend on the install

i know there are 2(well maybe its just one) companies selling SC kits that have them running 4psi without any tuning changes or anything else.

zoom44

sorry- no piggybacks or flash tune or anything BUT they use bigger injectors

https://www.rx8club.com/showthread.p...highlight=sema

earlier thread
https://www.rx8club.com/showthread.p...highlight=sema

SUPERMAC

red devil -- im actually not useing any engine management right now. i might decide to run an emanage or a canzoomer down the road. but it will all depend on how my car reactes without anything at all. i just want to know if i can run the car safely without the use of any other piggybacks and such. thats my number one concern right now.

zoom44 -- thanks for the info. i have seen this kit before and i actually tried to supercharge my 8 a while back with a v1 vortech unit. however i couldnt locate a certain bracket that i needed to stableize the unit and it was chewing up my drive belt in just a few miles from engine movement. therefore i had to scrap the project rather than waste more money on it.

thanks a lot,

chris

Red Devil

Well, if you're confident in doing this, great. I think you have a lot more know how than I. But those SCs that run 4psi without engine management, positive displacement by the way, are 4psi, and nothing more. I'd be more concerned doing this with a turbo because of the possibility of boost creep while you are fine tuning the turbo to your car. I guess the lack of margin for error is what concerns me. You can tune in a good safety margin with an interceptor or emanage, with your proposed set-up my eyes would never leave the afr gauge.

Brice-RX8

I have a feeling that if you are going to turbo a rotory without any engine management then you better have some money set aside for a new engine. You're best bet is to spend the $1600 or whatever it is for the Interceptor and be able to keep the engine safe, or keep replacing engines.

SUPERMAC

well the main problem im running into lately is that none of the local shops around the nw are willing to tune my car for me without the chance of ruining it. they simply say yeah we have experience with (emanage, aem, whatnot and so forth) but then they are like however we dont normally do rotary cars... and im like well have you ever done an rx8? and 9 out of 10 have said nope this would be the first turbo rotary we have touched.

so im like screw this. if im gunna hurt something i would rather it be my fault. that way i dont have to kill any service people for breaking my car. :D

MazdaManiac

iTrader: (3)

As soon as the motor touches boost, it will go incredibly lean.
I had to drive with my EMU off this morning (I had one of my solder joints go bad on my new ignition harness upon which I am experimenting, so I bypassed it which meant no RPM signal to the EMU).
I kept out of boost, but there were a few times where it saw 4 to 6 kPa (less than 1 PSI) and the A/F shot up to 19:1 and combustion broke up (BIG stumble).

The Ace

damn....

Anyway, even 4psi is close to 1/3 of a full 1bar boost (~14,2psi), so you are adding 30% more air to the A/F micture. I don't exactly know what duty cycle the stock injectors are running on, but I'm pretty sure the additional 4psi will push them to 90% or above. Not good.....

Hell, even the Greddy setup needs a piggyback or standalone, and it's also boosting 4psi......I wouldn't go very far with this "no piggyback" business if I were you.....

Brice-RX8

Well, I suggest that you do more research and maybe call Mazsport (sells the Interceptor) and see what he can do as far as tuning remotely. Granted it's your money and car, but there is no way I would jump into this without a tuning solution, and I definantly wouldn't let anyone tune it that doesn't have rotary knowledge.