ioTus

OK, could i get an estimate power rating rating for an s4 compared to s5 with the exact same mods (listed below):



>Super AFC

>FCD

>3" ehxuast system

>Small NPR FMIC

>GSL-SE secondary injectors

>Ported wastegate w/ stock turbo





What would the numbers be from one to the other?



Thanks!

~Geoff

1Revvin7

Its going to be hard to tell, just get on a dyno... The s5 will more than likely have more hp, its has lighter rotors...

ioTus

Yeah well i'm looking to build the car. It isnt built yet hehe. My engine is dead, looking to do an engien swap. s4 will be easeir, but i'm guessing harder to get more HP out of.



s5 would be harder (electric omp), but faster.

Corprin

why GSL-SE secondary injectors?

ioTus

they are 680 cc.

Rotaryman88

Run down would be this...



Same mods on both engines are going to result in very similar gains, but considering the S5 has a higher baseline number, your overall number will be higher by the end of the mods.



S4 = 180 Factory rating, roughly 162whp

Only the exhaust and IC will really NET anymore horsepower. The others listed are more for tuning. You will probably net 2-3 more PSI, putting you close to 9-10. With the FMIC you can run higher levels, but the stock turbo craps out if you run it at over 11psi too often. With the gains from the PSI..you'll net another 20-30whp..putting you closer to 190WHP, to 195WHP. After tuning, you may bump that closer to 200 at the ground and stay pretty safe. However, I have seen a S4 motor dyno at 230WHP with exhaust, intake, and tuning mods(injectors, s-afc,etc)...so it all comes down to the motor's condition, and how well it's tuned.



Now,

S5 = 200 Factory rating, roughly 184whp. Pretty much the same that I mentioned above applies here, except your baseline number is higher, by about 15-20WHP...so expect to have 218WHP to 228WHP after your mods.



Keep in mind, this is my opinion, I have no dynos to prove this, this is just out of past experiences, and everybody is more then welcome to correct me if I'm wrong

ioTus

Thanks rotaryman88. I may also look into larger turbo or something a bit down the road, but for now i'm going for a car that actually moves on its own propulsion, and not me pushing it down the driveway!! ehhe



I'm thinking of goign series 4 jsut to solve the electric OMP issue w/ the gsl-se front cover to put in my FB.



thanks for all the input guys, out of all the forums i post on, this one is the most informative.

Scott 89t2

Rotaryman88 you're missing the fact that the S4 comes stock with 3psi less boost... both engines at the same boost are very close power wise.



you add basic mods to both and run the same PSI on both and I bet it would be pretty close.

1Revvin7

But I also heard that s5 have a better intake design? Bigger primary runners or something..

Suds

Higher comp in the s5 (9.0 to 1 instead of 8.5 to 1) and a stronger rear plate. S4 engines over 400whp like to crack those rear plates. If you plan on going over 400whp get a s5 block.