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):

 

ewww...dynapack. what, too chicken to dyno with your wheels on?

all joking aside...just want to point out that your calculation is based on peak hp and peak tq. the RSS plenum's claim of 20+hp is in the mid range. around 4500-5500RPM if i remember correctly, to find it you just need to manually trace it on the computer.

the peak hp doesn't change all that much with the plenum. so what you see combine with exhaust looks about right

 

Here we go again!

I guess this is one way to get the traffic on this forum moving again.

 

Agreed, I am not a fan of dynapack dyno's. At a minimum at least a dynojet or a DTS dyno. Also note it is estimating flywheel hp not rwhp.

Anyway...it does look like he had some good gains..

Dave

 

I felt the hp gains when i installed mine. By the way, I have a used one for sale if anyone is interested. It will fit 997/997S.

 

Its pretty easy to see just by looking at the design aspect of the plenum, that it makes power....

 

Sigh. If only life were that simple....But, just think. If you were depending on folks to tell you what to do with this piece you would have removed and reinstalled it about 27 times.

 

Anyone know how I can get a hold of a member in this forum. I am a new member to this forum, thus I'm trying to learn how to navigate thru this site. His name is jabed92694

Luc

 

Luc - you can read private messages sent to you, but you need 10 posts or more to send a private message to a member.
If you like, I can send a note on your behalf and ask him to contact you.

 

And post 7 more times reply to this post and you're down to 6...

 

Message sent- copied you on it as well.

 

thanks Kurt...