O.K.
I have a question. My freind has an S4 TII with an RB exhaust from 1987, and an fcd about as old. I am doing a TII conversion to my GXL. I will have an S4 block with an S5 intake manifold, AFM, boost sensor, and turbo. I will have an FCD and a custom exhaust. 2.5" pipe-highflow cat-Magnaflow mufflers. I am a more experienced driver But I was wondering who would be faster. The S4 or the S5.
peace,
Charles

 

barring the conversion goes ok, you would be faster mainly due to the fact the the s5 turbos produced more power. One factor is they ran more boost, another is the manifold the s5 bolts up to are a lot better than the s4.

Be a good race i bet.

 

Sweet.

 

Well, the s4 and s5 have the same times in the 1/4 due to the extra weight of the S5 I believe. You're also converting the heaviest hard top non turbo to a turbo, as well as using lower compression and heavier rotors due to the s4 block. If everything were equal I believe the S4 will be slightly faster, however you say you're a better driver so that little advantage might be negated.

-David Guy
Andern Research Labs, LLC.
dguy@andern.org

 

Are you running an NA block with a turbo added or a TII block?

 

Full TII conversion. Block, tranny, diff. everything. And I'm gonna lose some weight in the car as well.
Charles

 

Sounds like you two are about even except you have a more efficient turbo..so i'll give it to you if ur a better driver...

I have about the opposite S5 TII block/Intake Manifolds, S4 Turbo as a loner.

 

Heh, I ve been driving him around for the past 3 months because his car was broke. I also race a helluva lot more than he does. I have prolly 3 time as much track time than he does. I'm not sure if I feel like beating him in the 1/4. He thinks hes the **** in the twisties but he has never even been on a twisty road. He pisses me off sometimes. He thinks that just because he can drive good in video games with joy sticks he can drive like a god on the road. I still beat him in thoughs vid games. I just want to let this punk know what hes dealing with once and for all.
peace,
Charles

 

S5....

I raced a friend with an AE, we pull about the same. He gets a jump on my at launch since my clutch is going, but from a roll, we stay door to door. Here are the mods:

AE - 120K miles Bonez DP & cat, RB mufflers, balanced injectors, K&N drop in

mine - 155K stock exhaust, dirty injectors, K&N drop in.

 

eh...I'd say your friend needs to check his compression. I think it's accepted that stock for stock s5's are faster, but once mods start going on this is totally out of the window. Or maybe the bonez dp just doesn't open up the car enough. With just my dp/mp and a cone filter on the TID I was trapping 103. That's like 9 mph over stock with a simple bolt on. I don't think a full intake full exhuast s5 is going to be faster than a s4 full intake and full exhuast car. Yes I know s5 turbo has the nice dual wastegate design, and I hear a 'more efficient' mannifold...but I don't see where that comes into peformance. I will tell you that the s5's are about 200 pounds lighter to begin with, and that definitiely has an effect on peformance.

 

I think stock for stock the cars are equal, the S5 being easier to drive off boost or with the AC on since the slight bump in compression helps in that area. His motor is slightly tired and mine was bought from an original owner who took very good car of the car, I may have more miles, but it runs very strong.

S5 vs S4 mod for mod is equal IMO
S5 vs S4 stock for stock is equal IMO

It all comes down to individual setup and preferences. I like the S5 look, but the S4 mechanicals.

 

its more like the other way around... an s5 t2 is about 150lbs heavier than an s4. the 0-60 and 1/4 mile times are pretty much the same... s5 is maybe 0.1 seconds faster

 

I can't believe you're asking this. this is elemantary, and i would expect more out of someone who's been on the forum as long as you! I've owned BOTH, and the S5 is quicker and a far better design. a little more weight, but nothing that can't be brought down reasonably.

 

heh thanks for catching that, I type to fast sometimes


quicker stock for stock, or mod for mod? Why is it a far better design (peformance wise) than the s4. There are a few things I like about the s5:
1. front spoiler/ rear spoiler/wheels (cosmetics)
2. turbo has the nice dual wastegate passage.

aside from that I really don't see why the s5 is superior to the s4. I'm not trying to 'defend' the s4 I just want a non bias input from someone who self admitedly has owned both.

 

i've raced one S4 10th AE in my 91 T2

he had:
fresh malloy mazda rebuild
3" DP, MP
RB catback
SAFC, cone intake,
S5 turbo w/ported wastegate...
from a 3rd gear roll, he was at 8psi

i have:
stock motor
cone intake, Bonez 2.5 DP, ,MP
50mm RP catback, ,ported wastegate
hitting 7psi from a 3rd gear roll

after flooring in 3rd gear at about 50mph, we were dead even for a few seconds and then I pulled maybe a half a car...

i was super stoked seeing that he had more mods. He did have a passenger, but I guess my S5 T2 was heavier to begin with

 

The s5 (stock vs stock) is .2 faster in the 1/4 (easily made up with driver error). I think the s4 will be a little faster, in your case.

 

I have been here for awhile, But I never really cared about performance of the different cars until now. I'm also sorta new to the whole turbo thing. You could say I'm a converted N/A guy. Goin to the dark side. I'm getting more up for mods and speed these days. The punks over here are getting anoying.
peace,
Charles