I just want to know what is better: An S4 Trurbo or an S5 Turbo? What's The Difference? I already know I'm gonna get flamed for this but I really want to know. I have an S4 N/A I want to convert and I'm trying to get some opinions and I've Already read the FAQ's and searched threads and it offered lot's of great info, I just am looking for a little more info. It also says I shouldn't convert to S5 from S4 but it doesn't say why? Thanx to anyone who actually answers this.

 

I think the answer's in there somewhere but...

Go s4 turbo b/c you can just drop it in and plug it in. The s5 wiring isn't compatible, which means you have to manually redo it all, etc. The s5 turbo has more horsepower, but only because it has more boost. With a little self education you can do the same to your s4 turbo.

 

Thanks. So it's pretty much boost alone that makes the difference in HP?

 

Rotary Ressurection has more differences listed between S4 and S5 if you're wondering about anything else.

http://www.rotaryresurrection.com/2ndgen/techmenu.html

 

Misleading info...the S4 NA to TII conversion isn't plug and play, although easier than swaping between S4 and S5. Harness mods. are necessary, both inside and under the hood.

S4 to S5 TII: turbo's and manifold and contol are different, the rotors are lighter, but I'm not a turbo guy, so don't remember much more. Oh, 182hp vs. 200hp in case you haven't seen the numbers.