Moostafa29

You are right, but keep in mind what the greddy turbo was designed for. N/A, we dont' lack power above 7k, our problem is getting to 7k. This turbo just complements our powerband, and gives up power where it is needed (ie. low/mid range).

Spyder_doo

Dont get me wrong but I thought the stage 3 kit for the srt-4 was an upgraded turbo from factory? What would you consider fast?

evilbada1

sorry if i didn't make myself very clear..
what i meant was greddy has chance against n/a cars with simple bolt ons, but not factory turboed cars with simple bolt ons..
anyhow, someone mentioned awd system makes evo, sti monsters..
from dig yes, from roll no.
what makes them monster is their potential.
like i said, simple bolt ons yield as much as what greddy offers rx8
but do i want those cars? no, they're ugly, i would've considered cars like that if rx8 wasn't out.
what i was saying is greddy does not accentuate rx8 and it is not competitive in terms of power.
350whp+ in rx8 however, is more of a competition to those cars that i mentioned
(it will mostly outrun those that are even slightly modded).
my point is greddy turbo is purely for the fun, not for competition.
seriously think about this,
you go to a local meeting where there are bunch of rx7's , evo's srt4's and sti's.
will you be confident with your power and say you pull 270whp or wutever at the wheel in front of those guys? in order to at least hang with those cars, you need at least 350 at the wheel.

Fanman

Yes, you are correct, the boost declines starting about 7000 RPMS. When I was looking at the kit, I was looking to help the low/mid range of the car. Top end was fine. It's not like it has nothing at the high end. A Greddy turboed RX8 will still whup up on a NA RX8 throughout the rev range, including the high end. It's a bit of trade off with everything. The T04 based turbo kits are saying that boost won;t hit until the 3500-4000 RPM range, then you lose the low end boost. Honestly, I would rather have the low end increase in TQ, than the top end power. For me, my car is an everyday driver, & I really appreciate the low end help.

Fanman

I can agree with this. The Greddy kit is a good street/everyday kit for not much $. Pretty soon we will have bigger/better kits but for far more $$$. Depends on your priorities. Evo's, STI, etc. are like putting a nice hat on an ugly dog. There is a reason we (RX8 owners) didn't get them. I don;t know of many NA cars where you start with low hp & can get high hp for little $. Not the RSX Type S, Not Toyota Celica, etc. Nissan 350Z's the FI kits are $5K+, Mustangs & GTO's start with 300-400 hp stock, & of course the FI'ed cars. If you want maximum hp this is a poor platform to start with. Much more of a balanced car (For example the Acura Type S won a comparo last month in Car & Driver vs. SRT-4, Chevy Cobalt, etc despite posting slower times) or the RX8 winning when they compared it to the Mustang Cobra, Infiniti G35.

evilbada1

compressor wheels and turbine upgrade from factory with the ecu if i recall correctly,, but its still no where near big turbo upgrade (T04R, 60-1 ect, ect)
what i consider fast is 12 sec car.

evilbada1

sorry about keep double posting, but i dont' think rx8 is a poor platform at all.
at least not if you aren't exceeding 400whp. of course there would be things that need to upgraded as power comes along, but i dont' see a reason why the renesis can't handle 400whp. Well, i'm not even going that far,, i think i'll be happy with 350whp. And yea, the greddy is cost-effective. but there are tradeoffs.
i wouldn't mind spending 8k to make my 8 to reach 350whp. That's IF it only costs 8K.

StealthFox

well, while the rx8 isnt a platform for a fast car, i think it has such good qualities that are overlooked by the masses simply because its magazine times arent as good as other cars in its class. I think the money it costs to spend to make the car fast (8-10k) is well worth it because while you may have spent a lot to make it fast you now have the speed of the other cars and everything they dont (refined styling, interior amenities and quality, awesome driveability and handling, etc) plus when you put it into perspective, nissan Z ownesr spend typically 6k+ on thier FI, and theres lots of people running the greddy TT setup which ends up being about 8k after its all said and done, so spending 8k on boosting the 8 to 350 isnt as rediculous as some make it out to be.

Rotary Rasp

iTrader: (2)

Has any company tried using a variable vane turbo on the rx-8 yet?

Fanman

Those are the exact reasons why I chose the car. I think this car is good for an honest 260-300 whp. We are lucky in that we have a greddy kit, that when all is said & done you are looking at about $5K for 240+ whp, or you can step up to the PTP or SSR/SFR units & get 300+whp for $7K-$8K. 400 whp sounds awesome but nobody has really had that long term, everyday driver, except Manuel & those PR guys. Cars like us, S2000, RSX Type S, Celica, etc. It takes $ to make a fast car, but these cars have a lot of other features. If max hp (400+ hp) then the SRT-4, 350Z, Mustang GT, GTO, EVO, STI would be better platforms, but like you said tradeoffs. Hell, put $5K in the Mustang or GTO & you are looking at 450-500+ whp easy. Depends on how much people value hp vs. other aspects of the car.

evilbada1

now we're on the same page.
yes, there are many cars out there that will easily be fast as hell with minimal amount of money. I want to make my 8 fast enough that it will have no problem hanging with those guys but still outway them in every other aspect. while ptp and sfr may not get you over 400whp, that is not what you want from an 8. i would be completely happy with 350whp.

Moostafa29

Bottom line, no matter what car you have, and how much you mod it to make it faster, there is always going to be someone faster than you. Its a vicious cycle. Just get your car to a level you are comfortable with and be happy. There, entire thread condensed in one post. :p

MadDog

Two points:
1) I was on a autocross track with an STi a couple of months ago. At that time, I had zero track experience while the driver of the STi was not a newbie. I have no idea if he was moded or not, probably not. I had the Canzoomer installed which gave a dyno verified 15HP gain. I was by far the fastest 8 on the course. The STi was faster than me in the straights, but not blowing me away. I was hanging with him in the turns and probably could have done a lot better than that if I had any experience.

Since then I have installed the GReddy turbo. I'm only running 5.5 psi, and I haven't dynoed or tuned it yet, but given the extreme difference in power, I am pretty sure that if I couldn't pass that same STi on that same track, a decent driver could probably leave him in a cloud of dust. With the turbo the difference across the entire power band is remarkable. Its a totally different car altogether. Until you've driven one, you really can't appreciate the difference. One of our fellow members drove my car and then couldn't believe how bad his own car felt on the way home! And this is only running 5.5 psi and a really conservative tune! This leads me to my next point.

2) properly tuned the GReddy turbo doesn't really loose power at high RPM. Take a look at Adrian-1's before and after dyno chart. The HP is certainly not increasing at the same rate over 7k RPM, but its not loosing power like the pre-tune dyno.

As for me, my 8 is not running super rich in the upper RPM range like some. I don't feel like its loosing power, but I haven't dynoed yet. My car is acting exactly like GReddy intended, 10.5AFR across the board with the GReddy map as shipped, and the ECU isn't trying to lean me out yet either.

Rotary Rasp

iTrader: (2)

Are people just ignoring me?

Moostafa29

Does anyone hear anything? :D

What did you say/ask?

Rotary Rasp

iTrader: (2)

:p

Moostafa29

The only S/C that I'm worried will be better than the turbo is Hymee's. It looks like it will be a beast. I think with all the time spent developing the Pettit, Axial Flow, and Hymee, the drivability will be better than an untuned GReddy, but that is purely speculation, and also depends on what ems they use to control it. As far as a variable vane turbo...I have no idea.

Red Devil

Isn't Hymee's even an autorotor like Pettit's? I seem to recall is simply a larger model to push more cfm.

IZoomZoomI

yup, the development of the s/c is coming along should expect it by years end the way they're going. The blower is considerbly larger but biggest thing is I think they're going to offer motec as an option for fuel management. Hope they can find a way to use a m48 or m400 with the unit instead of the m800 later on to save the customer some dollars w/o the sacrafice of flexible tuning.

If you live in the states the only downside I see with the hymee kit as oppose to the other sc kits, is the shipping cost, should jack up the price by a bit. But I suppose if you can afford a blower with motec you can't really stress about paying for shipping .

Red Devil

A complete standalone Motec? Or is it closer to the Interceptor EMS? I actually just spent a while looking through his thread, but maybe I missed that...

StealthFox

its not the kits limiting power my friend, both kits run t4's, they are capable of approximately 500-550 wheel horsepower

its mostly compression, and a really good solid tuning system

Fanman

Oh boy, I think RG might have something to say on this one. He had a good explanation on how rotaries will not put out the same hp as "regular" engines with these turbos. So while a 18G Greddy unit has gotten 400 hp on a Mitsu., it is virtually impossible to get it over 300 whp on our rotary cars. Same thing with the T4's (which the PTP kit will be swapping out to GT35 instead). While they have other cars putting out 500-550 whp with the unit, our limit may be closer to 400 whp with our engines. I know for example HKS's monster T51R turbo has easily put out over 800+ whp on a Supra were maxing out at around 500 whp on RX7's. There are a few more items to it, but in general same turbos on rotaries does not equal same hp as other engines...no matter how good the tune (or compression) is.

Fanman

I could see Mazdaparts.com & Matt selling this unit, as they already sell Hymee's exhaust. Might be a good distributor for Hymee parts here.

IZoomZoomI

I think its going to be the same thing, not sure what the difference is, the only difference I see is the price tag, 3300 for motec unit..

Rotary Rasp

iTrader: (2)

How come nobody has tried a twin turbo set up. That way they could use two small turbos. Is there not enough room?