I'm currently in the process of building a D15B7/Z6 mini me. I'm planning on dropping a stage 2 crower (all motor) cam in the head, and leaving the bottom end alone. My question is what sort of RPM tolerance do the Z6 valve springs have? I know the stock redline is 7200, and I wasn't planning on revving past 7500, since the D15B7 has weak *** rods and, from what I've found, the bottom can't take revving very high because of that. Would the stock valve springs be able to rev to 7500 with that cam?

 

stock valvetrain keep it at teh stock limit 7-7200... passed that would be a no no...

but i would get the valvetrain upgraded to get all you can out of the cam..

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by guardian_ang3l &raquo;</TD></TR><TR><TD CLASS="quote">I'm currently in the process of building a D15B7/Z6 mini me. I'm planning on dropping a stage 2 crower (all motor) cam in the head, and leaving the bottom end alone. My question is what sort of RPM tolerance do the Z6 valve springs have? I know the stock redline is 7200, and I wasn't planning on revving past 7500, since the D15B7 has weak *** rods and, from what I've found, the bottom can't take revving very high because of that. Would the stock valve springs be able to rev to 7500 with that cam?</TD></TR></TABLE>

Rods aren't really the weak point. It's the rivet-sized rod bolts. ARP's should be on order.

 

its actually a combination of a rod that is way too thin for what ur doing and a rod bolt that has no business even being in an engine.

d15b7 rods and rod bolts are incredibly thin and weak and by no means should be used for higher horsepower applications unless u have the money to replace the block after a while. there notorious for self destructing.