hes talking about the different grinds you can get on the cam lobes. it changes how far the valves open and for how long they are open. you dont want too much lift on the stock head or the springs can bind.

 

^ It'd be useless on a stock head.

 

Stock as in no port work or stock valve train?


Going with some cams without any port work should some some gains with the right turbo setup.


I ran schrick cams with stock valves/valvesprings, pushing 500whp and up to 8k rpms without any issues. After 8k I ended up floating the valves.

 

mike do you still have your hydraulic lifters on there?

500hp and 8k rpms is a little dicey with the stock valves n springs, no? i thought the stock sodium filled exhaust valves dont hold up very well at those power levels. i mean sure you can get lucky and not drop a valve but wouldnt it be best to just make sure that wont happen?

you do seem to have a bit of luck on your side though, i saw the exhaust wheel of the 30r you pulled off lol.

 

Yes I still run hydraulic lifters and run them to 8200-8500 rpm every time I run the car down the track.

I have aftermarket valves/springs/retainers now, changed them out when the stock ones got bent after they floated and hit the piston.


Well its not power thats a problem, its very high EGT's that could cause the stock sodium filled exhaust valves to fail. Time is also a factor. Thing is in the last 9 years I haven't really seen all that many A4 owners drop a exhaust valve, not even on A4's that are 11 years old with high miles. Yes it might be best to change them out at some point, going with solid aftermarket valves when trying to make big power or looking to push beyond 8k rpms.


Yeah still not sure what damaged the exhaust wheel, might even have happened way back when I used to use the "anti-lag" which was way back in 2005-2006.