Hi there everybody,

I just purchased my first RX8, a 2004 with the Sport Package, and the Performance Package, with 26k miles, and Im very excited.

As much as I love the car already, I'm yearning for more.... power.

I was wondering, without adding a turbo or supercharger, what upgrades would you recommend me getting and how much added power do you think I could realistically attain?

I don't have anything against FI per se', but I don't have $7500 to invest in the supercharger, and Im not a big fan of turbo lag. If I could spend $2-3k on other improvements and be able to add say, another 40-50hp, I'd rather do that.

Thats if Im not asking for the impossible.

Any help appreciated, thanks

 

Fraid your only going to get maybe 20-30HP with all of the bells and whistles NA

If you want any larger increase you need to go FI...

Do a search...there are a lot of threads on NA upgrades and what you can expect for increased power from them

 

before you write off turbos, do you really know what turbo lag is?

 

int-x, straight midpipe, and maybe higher diff ratio. those will make you think you have noticeable power gain if you REALLY wish to stay away from the turbo or sc.

i heard mixed reviews on the intake and exhaust. they'll probably add 2-3hp's each, i personally don't think they're worth the money but who knows? there can be some good stuff out by now.

greddy turbo has almost no lag with our rene. used one can be had for 2k. i'd definitely add the interceptor-x if you're getting any FI solution.

you can turbo your car reliably for 3k. if you have 3k, that's the best thing you can do to your car imho.

 

How about some nawzz yo.

Search zex, read, score.

 

How about some nawzz yo.

Search zex, read, score.

 

or you can do that: nos.

 

? 3k? is that including an ecu?

max power without FI.....thats why im going NA 20b.

 

yep 3k w/ emu. about 1800 for used greddy, 1000 for used int-x, .200 for used wideband? haha. it's close enough.

are you serious about the 20b NA? i think it'll kick some serious ***.

 

I guess not. I guess I would like more power (especially torque) in the lower portion of the RPM range, and I assume that the supercharger, not the turbo, would be the answer, and I don't have $7k to spend on that.

Please correct me if I'm wrong, I admit I'm a noob tuner and pretty ignorant on the turbo subject.


PS...thx for all the answers and info everybody ... I really appreciate the input

 

Just think of when you switch a fan off, its slowing down right? but for some reason you want it to go on Full again, you switch it on, but it takes couple of seconds before it can go *Full speed* again.

So Turbo lag is like, you're driving 50 @ 8K rpm, you slow down, the speed drops, also the rpm of the turbo drops, it went down to around 30 mph @ 5K, then all of the sudden you want to pass somebody, so you step on the throttle again, but the turbo is slowing down, it takes some time before it can blow enough air to support the speed.

SC can give you more lower end TQ, but it usually dont kick in until at least 2K rpm.

 

A turbo spools up based on exhaust flow. It needs a specific amount of exhaust flow to build up the boost. So if you floored the throttle at 2,500 rpm, by the time you hit 3,000 rpm, you'll be making 5 psi boost. And by 3,200 rpm, you'll be making 9 or 10 psi boost. See the dyno chart in my sig for an example.

What this means is, if you're driving at 4,000 rpm in 6th gear, and you mash the throttle, your rpms are high enough that boost will come on instantly - your car has enough exhaust flow at that rpm to do it without building up slowly. In reality, as long as you're above 3,000 rpm, boost is always there. If you're 2,500 rpm, it will build up quickly and there will also be no issue. But if you're under 2,500 rpm, then it would be slower to boost.

With that said, next time you're out driving, check out your rpms and see if you are ever under 3k and floor it. It will be slow in your NA car, and it will also be slow in a turbo car. If you pick your gears properly, it will never be an issue.

The pettit SC has an advantage in boost under 3,000 compared to the greddy, but it's a minor advantage for two reasons: 1. The boost level under 3k isn't very high on the SC, 2. No one would ever be racing from a dead stop starting at 1,000 - 3,000 rpm. Above 3k, the SC doesn't make nearly as much torque, and can't compete until rpms are near redline. Meanwhile the greddy can get peak torque from 4-8k.

 

I would be happy to see 210 at the wheels, 2,500 deep and prepared either for a s/c or some nitrous... The more little things you do to your 8 the happier you will become, but what the people with post counts above 1,000 say is true.... haha

 

I recently discovered that my tuning for my EMU was too rich in the <3000 RPM range.
Its been that way for over a year.
I never noticed, because I never tried looking for boost down there since I did the initial tune, other than to prove that it does make boost down there.
I don't think I've ever had the car <3000 RPM and tried accelerating at WOT.

 

1k on full nitrous setup 1.4k on EMU and the rest u can spend on the bolt ons will nail u about 50whp with a 75shot tuned

 

If you're like me and the 8 is your first rotary car, what you're really missing is TORQUE.

The N/A mods won't give you what you want.

Also, a rotary isn't to be driven like a big V-8; it wants to rev so you need to drive it with a mind to keep it in its very broad powerband (3.5k-9k).

The rotary's exhaust gasses are really hot, which means there's more energy to spin the hot side of a turbo, so lag is minimal...about like what happens on an old hot rod when the 4-barrel kicks in.

You'll also dig the increased torque at less than WOT, since it improves overall driveability.

And, as others have said on this thread, a used GReddy kit will fit your budget; especially if you do the wrenching yourself.

 

The EMU only costs $700 bucks


And to the OP; a properly sized turbo will give you virtually no boost lag. Just downshift. Anyone who tried to floor it from 4 grand in 6th gear is a retard, the car stock won't even move

 

The best Speedsource was able to do with their race Renesis engines for ST class was 260 bhp on their engine dyno. There is probably a bit more to be had if you port the motor like Ray and RG did.

 

finally - something to savour


you should post up the latest Pettit dyno on your thread- think you would find that advantage is not there now that the kit has evolved .
Remember how the greddy kits were only reaching 240-250 whp when they first came out - they too took a whuile to reach full potential .

 

r u talking about the e-manage ultimate CW? I was talkin bout the INT-X...........I wouldn't consider the e-manage ultimate unless MM lived close to me

 

I'm in Long Beach 4 or 5 times a year.

You really need to drive a Pettit car and a turbo car back to back before you "savor" anything.

 

yeah, really. everything changes when you get a chance to drive one.

it's great and all to be NA, that's the way i really wanna stay. but there's no need to exclude it for FIs 'downsides'

g/l, and you're not the only one keeping it NA!

 

^^ I don't think you quite got the gist of what I was saying there...

 

hmm, i probably don't but i hadn't posted in a while and i felt like posting something.

even if it didn't make sense. i think maybe i've been reading too many of taj's posts! jk

 

I don't understand why everyone thinks the Ultimate is the devil. If it is wired properly it is probably the best engine management unit for the power levels the RX8 community is currently seeing. Granted, it has limitations with the timing but we only have 5 or 10 cars that are producting the power numbers that will require more timing adjustment ability. If the Cobb or some other reflash unit is released the timing limitations will no longer be limitations and people will be able to daily drive 400+ horsepower cars without a CEL and without disabling any of the RX8s features.