jsquad561

im buying a rx-8 AT 4speed

i want to make it go 0-60mph in 5.1sec - 6.0sec
thats my end goal.

but I want to spend less then 10grand 6 or 7 would be nice

can anyone give me a honest run down on what i need to get and do?
and i need a plan that works and wont blow my car up i want it to last plz i really need a str8 answer no theory BS and no i cant buy a MT i just cant dont ask.

JTtheDude

If you truly want to reach that goal don't buy the car. You'll need a MT and FI.

TopGear8

iTrader: (3)

If your just looking for a car to go fast in a straight line this car is not the car for you, just buy a mustang or GTO or something. If you really want the rx8, then you'd be spending alot of money, Turbo and alot of other mods.

tajabaho1

5.1-6sec? 4at? sounds like turbo only

Phil's 8

iTrader: (3)

Do your self a favor and do not buy the car. You will just become another poster complaining about the lack of power. The m/t is presently capable of what you want but not for what your willing to spend. The a/t may be capable but it will cost you much more than your budget. Of course your young and you know more than we do so you'll buy the car, blow good money on it, be disapointed and knock the car.

chickenwafer

iTrader: (9)

if you only want to go 0-60mph in 6 seconds a stock MT can do it if you can drive.

But it sounds like you just want straight (as you said, str8, yo!!) line performance so don't buy an RX-8, let alone an automatic.

sosonic

Your only hopes are a twinscrew supercharger or turbo at high PSI giving low end boost. Your in luck, Hymee has such a supercharger in development and might be close to releasing it and Pettit is developing a higher PSI version of its presently released supercharger. There are some high powered turbos out there as well, but they need to provide boost on the low end and without lag to help the auto. This is because of the torque converter limit of around 2,500 or so rpms. You can't launch past 3k rpms, so you need a lot of boost to compensate or need to get an custom torque converter made. There has been talk of doing some PCM tricks for the auto transmission, but few seem to be working on it.

However, you will need data on what HP and enhancements it would take to get an AT down that time. Unfortunately, the FI guys don't release that kind of data and many FI kits are still very new. People selling the FI kits seem to be really shy/scared to release any data because it might affect sales.

The problem too is there is like a 325WHP or so barrier before various other engine parts need to be upgraded to handle additional power. Add to that, nobody at near 325WHP has released their 0-60 times.

Your best bet to get that data at this time is from the guys running NOS, who also will do 0-60s. But the problem there too, is nobody seems to be running 100+ shots of NOS and they will have upgrade issues with the higher NOS shots . I'm not even sure if they are too many even running 75 shot. The only person close , seems to be Charles R. Hill and he has a manual (though has done some work on Autos).

I do think next year this time, enough people with FI kits or running higher NOS shots, should be able to give or not be shy about giving their data.

jsquad561

This turbo costing 3,500
http://www.turbo-kits.com/rx-8_turbo_kits.html

its greddy and im guessing the 260WHP is on manual so A/T should be................. if you substract 30 or 40whp so that puts the A/T in about 225whp ballpark

ok so, post me if im wrong.....but

if the mazdaspeed 3 does 0-60 in 5.8sec and has about 210-220whp shouldnt I have a 0-60 of 6sec or a little under?

the PSI is 5.6 on this turbo kit

so with this said have i met my goal simply by buying this 3.5k turbo and staying well within my budget? thats what it looks like............

mdw1000

One thing you'd have to find out with that comparison is how did they launch the MS3 to get that time. Did they rev it to redline and dump the clutch, etc.

Also, with the AT you are going to be 30 to 40hp short at the crank. At the wheels you will lose more than that due to the fact that an AT has more driveline power loss than a MT.

tajabaho1

not for the 6 ports though, we lose a bit less

mdw1000

You still are going to lose some power due to the fact that you have a torque converter. As far as I know they are all less efficent at transferring power than an MT.

The 6-port loses less hp. However, I have more torque than you

sosonic

At the same HP, the automatics have MORE TORQUE than the manual. The automatics have a "hidden advantage" that has yet to be exploited to its potential.

Mazda limited the RPM limit on the automatics to protect the transmission. This forced RPM limit would have a greater effect on the 6-port as it has the same engine as the manual. A 6-port and 4-port could get some of that back by flashing the ECU (removing the RPM limit), doing some tuning, and using an automatic transmission cooler and better automatic transmission fluid.

The 6-port automatic has the same engine as the manual, so modifications would get it closer in performance to the manual. The 4-port engine may be considered as being different in various respects. However, FI would help it get more air at higher rpms and close performance gaps.

The main problem with the automatic's torque converter is you can't launch past 3,000 rpm, while a manual could launch at higher rpms... like 5,000 to 6,000 rpm. The actual launch would make a major difference. All other things being equal between the manual and automatic, the higher rpm launch of the manual would give them an advantage, however the higher torque of the automatic would help compensate.

If you don't get the torque converter customized, than the automatic needs low end boost to compensate. This is why superchargers that give full boost at 2,000 to 2,500 rpm would be so attractive.

For a manual, this is not a concern because they can launch their car at above 4,000 rpm and be in full boost with turbo. Often 4,000 rpm is where many turbos will kick ***. Automatic owners however would be more concerned about turbo lag, boost lag, and low end performance (1,500 rpm to 3,000 rpm). They also would need a FI kit that gives lowend and highend performance, which again would make superchargers attractive.