hmmmmm?
11-10-2008, 12:20 PM
#1
AudiWorld Member
Thread Starter
Join Date: Feb 2004
Posts: 409
Likes: 0
Received 0 Likes
on
0 Posts
hmmmmm?
what do you guys make of this<ul><li><a href="http://www.rs246.com/index.php?name=PNphpBB2&file=viewtopic&t=7 3889&sid=7daf924432873bea9b6b121be36cc4c2">htt p://www.rs246.com/index.php?name=PNphpBB2&file=viewtopic&t=7 3889&sid=7daf924432873bea9b6b121be36cc4c
11-10-2008, 12:26 PM
#3
AudiWorld Super User
Join Date: Feb 2003
Posts: 16,402
Likes: 0
Received 0 Likes
on
0 Posts
I don't believe it. Here's why.
The gains appear to be fairly consistent across the entire rev range looking at the torque curve.
If the manifold was a flow restriction, you'd see very little gain on the low end increasing to more gain on the top end as airflow increases and the manifold became a bottleneck.
The fact that the before and after shows a near constant delta between 2500 RPM and 8000 RPM leads me to believe there is some other effect at play...different intake temps, different timing, different A/F ratio, etc etc etc.
If the manifold was a flow restriction, you'd see very little gain on the low end increasing to more gain on the top end as airflow increases and the manifold became a bottleneck.
The fact that the before and after shows a near constant delta between 2500 RPM and 8000 RPM leads me to believe there is some other effect at play...different intake temps, different timing, different A/F ratio, etc etc etc.
11-10-2008, 04:08 PM
#7
AudiWorld Member
Join Date: May 2007
Posts: 364
Likes: 0
Received 0 Likes
on
0 Posts
pdf says it's corrected hp and torque. He said no change to ECU/AFR.
Porting the manifold is an old hotrod trick and 7% is not outside the realm of possibility for an engine that's all about volumetric efficiency.
Trending Topics
11-10-2008, 05:19 PM
#9
Check out this info......
Intake manifold design is apparently already optimized. It seems reasonable that in designing an engine like the RS4, such a fairly simple measure wouldn't be overlooked.<ul><li><a href="https://forums.audiworld.com/a5/msgs/14363.phtml">RS4 engine design</a></li></ul>
11-10-2008, 06:44 PM
#10
AudiWorld Super User
Join Date: Feb 2003
Posts: 16,402
Likes: 0
Received 0 Likes
on
0 Posts
You're not seeing things here.
Correction has nothing to do with how heatsoaked the engine is. You can do multiple pulls on an RS4 and I can almost guarantee that each subsequent pull will give you less power than the last. It's very reasonable to think that a 20 hp swing is possible with no changes done to the car, ECU, or conditions.
The RS4 is a long ways from an old hotrod. Hundreds of hours of computer work doesn't leave horsepower on the table that can be freed up by some bloke with a 6-pack and a dremel tool.
The RS4 is a long ways from an old hotrod. Hundreds of hours of computer work doesn't leave horsepower on the table that can be freed up by some bloke with a 6-pack and a dremel tool.
