It's pretty much normal for the power to get a bit weaker right after 7K right?

I can feel a pretty definite drop off of acceleration when I go to 8K (although being able to rev higher does mean you can have the revs higher in the next gear, although that only matters when you're going full throttle between all the gears).

Yes, I realize peak power is like 7K.

 

I feel a definite drop in power above 7k. I think the stock tuning gets super rich up there and that's part of the reason for the drop off in power.

 

now is there the same amount of difference in the N/A S4's?

 

I think a lot of it is that its an older car with lower comression, so the power band is shifted down some. Plus it is normal in a stock port engine to drop off near the redline anyway.

 

my 172rwhp s4 n/a with s4 rotors and manifold still drops off after 7k, on the dyno and on the butt dyno.

 

the opposite is true, the sealing integrity is less important as rpms climb due to the reduced amount of time at the high rpms for gas to leak from the working chamber...

the sealing is most important at lower rpms, your low rpm torque will be down if the gas can leak becuase it has more opportunity to leave the chamber when its moving slowly.

 

My 86 has never seen 7k with me in it, so I wouldnt know, but I would say that it would drop off over redline for sure, you know, redline is there for a reason.

 

Yes, but the redline is 8K on the S5 (probably just because of the lighter forged rotors).

BTW, what the hell did you have to do to get 170+ RWHP on an NA?

A street port?

Those do change the powerband, though... I wouldn't think a streetport's power band would drop off until 8K or so...

 

The rotors aren't forged, but other than that you're correct. Even with my rebuilt motor it still drops off as the revs climb above 7k.

 

hope this is on topic, but........why does the automatic s5 redline at only 7000? how come the tach only reads up to 8000, not 9000 and shift at up to 8000? Not like it matters that the manual can shift at a higher RPM, but im just curious.

 

i'm not sure how he got 178 but i got 182 with mod. tb,rb header
grounding kit safc2 secondary ports welded open cs cat back with
cat delete on a low milage s5my own air box and intake piping 3.5"
noligy wires w/ ngks a few other things in there too
i dont have any power till 5000 though i also rev to 8500-9000
peak power drops at 8800
stock cars have a very rich condition after thay hit open loop at
6800ish but it can be tuned out

 

Oh yeah, they're machined, not forged... either way would be better than the cast S4 rotors (unless you're making a turbo drag car...lol).

 

Why haven't you redlined your car?

GO! BEFORE THE CARBON MONSTER GETS YOU!

 

The slush box can't take any more than 7000rpm.

 

^^haha thats wut i thought......damn i wish i had manual