1999porsche. Is this true for exhaust changes also? If so what changes can be made to increase peak power hp/tq? If not true what changes can be made for bang for buck excluding super/turbo charging?

 

It is my understanding that there is ongoing litigation between AWE and RSS predating the great dyno war debate. AWE reportedly ( this info came to me from a retailer of RRS parts for the record) used the RSS design for their own plenum piece w/o authorization. Those seemingly well intentioned AWE dyno runs showing "no gain" may not be as innocently objective as some thought. It seemed peculiar to me at the time that one aftermarket manufacturer would do what AWE did to another, ie RSS. Unprecedented as far as I know. My internal dyno has been sleeping well at night, as I have previously reported. Gerry

 

Actually, exhaust mods do effect peak power immediately as they effect the breathing of the engine and the wave scavenging in the exhaust. The subject is too involved to get into here, but the exhaust energy waves greatly effect the power available to the engine. Flow velocity also plays an important roll.

In short:

Longer headers will increase power below the engine’s torque peak and shorter headers will increase power above. If you increase the diameter of the headers and collectors, you will limit low range power and increase high range power. In contrast, smaller diameter headers and collectors will increase low range power and limit high range power.

Material of the exhaust headers also has a big effect on performance. Some materials, such as stainless steel, do not transfer heat to the outside air as fast as do headers made from steel. Keeping more heat in the header increases the exhaust flow which is beneficial to performance.

Exhaust mods are a compromise as are most engine mods. You can have more power at the low end and less at the top, or less power at the low end and more at the top. Or, you can balance it somewhere in the middle. If you are one who likes screaming down the road at high rpm's, then a more open exhaust would be for you.

Your 997 iis setup to be pretty efficient as it comes from the factory. Programs that adjust timing and fuel mapping can add some small performance gains, but any real gains requires forced induction or other method of increase 02 to the engine. Weight reduction is a great way to improve performance. Your's and the car's.

Remember, peak hp does not automatically translate into performance.

 

Thank you for the response. It helps with mods next in line

 

+1 this has been explained time and time again but always good to go back over it.

 

When I bought the plenum I did not buy it as a stand alone item . Just as an engine consists of many parts combined to operate the car I felt that modding required intergrating various aftermarket parts to create a desired result .

 

and the controversy goes on...

Too bad none of the disbelievers when to the dyno day to check things out.

 

I hope RSS does a dyno day here in Florida so I can attend.

 

I'd like that rumor to be put to rest here and now. We had no ulterior motives when doing our plenum testing.

There is no current, past, or pending litigation between the two companies, and when RSS pointed out the patent infringement possibility with our 997TT design, that was another reason for us to partner with them on reselling the product. We had discussed with them the possibility of a patent license if we also signed on to be their dealer. We had *every* reason to conclude that their 997 plenum made power.

In fact, we did find that their 997TT plenum made about 5-6 more whp over the stock one. Forced induction is a different animal from NA, though, so the different results between the 997 and 997TT did not surprise us.

I just want to go on record that we stand by our results 100%, we feel they were conducted in a rigorous scientific manner based on several years of in house Porsche dyno testing and product development, and we feel that we have satisfactorily demonstrated how easy it is to get a false positive or negative when dyno testing a modern Porsche.

Please let us not confuse the matter at hand with insinuations of ulterior motives affecting our testing.

Now back to your regularly scheduled programming!

 

Folks had a right to know upfront about your "history" w RSS, Todd, whatever spin you choose to put on it. Surely you have learned this by following the democratic primaries.

 

I see this debate is still raging. Greg at RSS has offered to dyno my car at another independent dyno. We will see where that goes. AWE is above reproach here. Please don't cast aspersions on AWE, they did this testing for us at my request. Time is money and dollars don’t grow on trees. I am thankful that they did this work. More later. \

Doug

 

Yes, no one is hiding the "history" here, I am just ensuring that it is documented accurately. Stating that there is litigation involved between the two companies is false, not matter how one "spins" it.

There was no hostility or bad will between RSS and AWE Tuning during this testing. If there was, why would RSS have even sent us product to test?

Let's leave the conspiracy theories out of this, because all that is doing is confusing the forum.

 

Or you might argue "why would RSS have sent us a product to test that didn't work?" Litigation, real or threatened or only in the realm of possibility is not the issue here. It is the appearance of conflict of interest. The dyno's in question should have been done by the consumer as far away from you as possible. There can't be much arguement about that in hindsight. Personally I find this whole thing tiresome at this point. No conspiracy but maybe bad judgement.

 

You are the one creating an impression of conflict of interest and I am here to set the record straight.

There was no conflict of interest, and just because you make insinuations of conflict of interest does not make it true.

Your insinuations are incorrect and have no place here. Please do not confuse the matter.

This is my last post here, too.

 

Then please STFU on this particular branch of the subject - you are the one dragging it out. The only valid party to contradict Todd's statements is RSS. You are not their spokesman. Drop it and move on.