Well there is more to valvetrain control than just spring pressure. The 918s have MUCH lighter total effective mass compared to the 987s and WILL hold RPM better, but its whatever. If you already have the 987s, then use them. They are good springs.

 

I cant understand why you would put a cam in and use the crappy stock rockers.They are known to be out of spec anyhow.I know money is an issue...but I like to TRY and do things right,at least get the roller tipped rockers....end rant.

 

I run the factory rockers in my Stockers. I go thru the traps at about 7200 rpm and have never had a valve train failure. Last year I tried swapping in a set of Crane 1.5 roller rockers and gained nothing!

Daren

 

The real killer for the stock rockers is spring pressure, too much over 350 pounds and they will have a great chance of failure.

 

Thanks for the replies guy's. Hey Gump how are you turning 7200? My pcm doesn't have ignition tables past 7k?

 

DFI

 

I see..