thendawg

Have a buddy's car Im working on that using the YT 1.7:1 rockers on stock LQ9 heads. The heads havent been clearanced for the rockers, but they appear to clear. I used a feeler gauge to check the clearance between the rocker and the side of the head, and through the entire motion (rotated crank by hand) they have about .004 to .005 clearance. Is this enough or will we run into issues down the road at high load/rpm? Ive attached a couple pictures for reference.

Bama99z

iTrader: (7)

Interesting, I personally think that is a litte tight for them JMO. I will be doing the same thing as soon as my new heads arive, I was told by several that I would have plenty of clearence with my heads TFS but I have never heard exactly what a acceptable dimension is.

garygnu

that is pretty close ,expect some valve train deflection at higher rpms.have you shimmed the rockers for proper valve tip swipe pattern ?

thendawg

Yes, ended up needing one .040 shim under each pedestal. Pushrods and preload were adjusted accordingly. Still waiting to hear back from YT and Texas Speed as to what they think about the clearance... Anyone else care to chime in?