[M758]

Originally Posted by mAd924

my sheet is in my cars garage info. the best run was 91.9kw = 123.24rwhp with approx 25% loss is pretty much still factory power.

Remove the cat and I bet you can pickup 7 hp easy. May be 10 hp. Most 944 spec cars put out 128 to 135 whp based on dynojet. I don't know any 944 spec racer that uses a cat converter.

One of the major problems with 8valve 2.5L NA motor is that there is an airflow restruction somewhere from the AFM to the head. Not sure exactly where it is. Some say it is the barn door style AFM itself, some say it is port design in the head (too big and that slow input velocity which limit cylinder filling at higher RPM). Personally I am not really sure. However what I do know is that the 944 NA 2.5L 8valve is insensitive to alot of standard tuner mods. Bolt on for the most part get you a fraction of the advertized gains.

Now the 944 Turbo is easy to gain hp due to the ease of adding boost. The 16valve motors use a different head and intake tract so their ablilty to gain power is different.

Not the reason I bring up 944-spec is that these cars are some of the few cars that have development looking for hp in the motors. We are regulated by the need to keep thing stock, but alot of our rules are stuctured around ways to keep power equal. If we allow a mod to be open or free it mostly because it does not do anything to change the balance of power. 5hp is good gain our class so if there was 5 hp to begaind by changing the airbox it would be done. If that required some $500 special airbox to it it would be banned for cost reasons.

However because it is open nobody had found anything yet. Most guys run the stock box because it works.