Hi all.

Do any of you have experience with dyno runs before and after installing adjustable cam sprockets on a stock engine?
I started wondering about this after reading the workshop manual, which says that the belt should be checked/ retightened after 1600 km`s I think it was..
I was thinking this maybe vould be a cheap tuning, although a time consuming practice..


Jørgen

 

Do a search on all the work done by Porken here. Latest was on +/- 2 degree moves on an S4. He used to make kits to put adjustable S4 cam wheels on 16V engines. Note that these are NOT things that make the timing adjustable while running! Sterling has fitted a 944 Variocam system to his S4 (GT?, Stroker?) some time ago, also listed here.
Please list your model year, type, and transmission when you post questions, so as to get the most relevant answers.
jp 83 Euro S AT 53k

 

Thanks! (and I`ll start listing)

Jørgen

 

My experience is only with 2 valve engines, there is a definite effect that can be measured. The advance on the cams will make the idle rougher, can get quite rough so you have to balance this with the increased power you will also get. On a 300 rwhp engine you can change the HP is a range of 15 to 20 HP with the midline of that setting in the neutral position.

 

I have found that there is a limited useful range for 16v and 32V engines as both have only one cam gear. If both the intake and exhaust cams on a 32V were adjustable, then there would be more tuning possibilities.

Advancing has the greatest palpable effect, at the expense of horsepower.

 

I should have said that only advancing the cams will increase power. Further retardation only takes away power.