Just wondering up to what rpm can they usually keep up with if anyone would know. Just curious.

 

I swapped to a pg7 ecu with the higher redline and no probs. Also I've been told they are safe to 8k but dont quote me.

 

several factors come to mind. on a pretty new/low mileage head, the stock valvetrain should be kool up to 8000rpm if acidentally revved up that high. but for racing applications, I would suggest upgrading to the Heavy duty single spring for added protection if it going to be taken up to 8K many times.

on these old D16A6, i wouldnt suggest revving up past 7500rpm since after many years of normal wear and tear the springs arent the way they used to be. so better to be safe than sorry.

Wil