RSS plenum gains verified on my 997- dyno results by p0rsch3

By stevegolf
( 4 )

3 minute read

RSS plenum gains verified on my 997- dyno results


Compliments of p0rsch3 @ www.6speedonline.com

I wanted to put this in a separate thread for those here searching info on the IPD/RSS plenum. Per my dyno tests last week and this week, removing the RSS plenum from my pcar definitely caused a loss in HP/TQ. IMHO the plenum works as advertised. Not sure if my estimated gains are average for this product, but I can guarantee it is remaining on my car.

Today's dyno runs without the RSS plenum (1st chart below)

1st run was with stock mufflers, kn intake and no rss plenum.

2nd and 3rd runs were with AfterHours mufflers, kn intake and no rss plenum.

We did six runs total but only a few are graphed because output was consistent. I left run 2 and 3 since there was some high / low deviations, could have been due to the dyno operator.

I wanted to see what additional gains the plenum was giving me at last weeks previous dyno testing. It is clear to see that removal of the plenum does indeed drop HP/TQ. BTW I drove for 1 week after taking the plenum off before dynoing today.

Shop temp was 80.5 degrees.

Last Week's dyno runs with the RSS plenum (2nd chart below)

1st run was with stock mufflers, kn intake and rss plenum.

2nd run was with AfterHours mufflers, kn intake and rss plenum.

We did six runs total but all runs were spot-on same with results / chart plot.

Shop temp was 80.3 degrees.

RSS Plenum Results Summary:

My stock muffler run was 257 TQ and 296 HP without the plenum.

My stock muffler run was 273 TQ / 313 HP with the plenum. 

-So a net gain of 15 TQ / 17 HP at the wheels with the plenum, stock mufflers and kn intake, not too bad for just a couple of minor mods.

AH Muffler Summary:

In both dyno sessions (with and without the plenum installed) the AH exhaust added an average 11 TQ / 11 HP additional gain over the stock mufflers. 

AH + RSS Summary:

With the plenum and the AH pipes together, I estimate a total avg. gain of 26 TQ / 28 HP.

So this confirms my feeling that the car runs much stronger overall with both of these mods.

This is my best attempt at trying to accurately document everything, which I hope helps others who are considering either of these parts for their pcar.

Nice job RSS for providing a product that works as advertised, at least per my experience and results.

Todays dyno chart (no RSS plenum installed):


Last weeks dyno runs (with RSS plenum):



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