SonicBlueFiveSlow

I've got a set of GT40P heads and I had the pedestals milled and drilled and tapped for 7/16 studs. I go to put them together tonight and it seems as though the studs are bottoming out before the nut part of the stud ever touches the guideplate. The studs are ARP 100-7101 with a base thread length of .750.

I'm wondering if I can get studs with a shorter base but what's really worrying me is that there was too much material taken off the pedestal. If I remember correctly, you're only supposed to take .230 off but it really looks like there is more than that gone. One of the tapped holes on each head actually went into an exhaust passage it looks like.


I hope I've made sense.

TrimDrip

The stud in the exhaust port should be okay. If they are too long, why not cut a thread off or two?

SonicBlueFiveSlow

Yeah, but if I have to cut them because there was too much material taken off the pedestal won't there be negative effects on valvetrain geometry? Or will it be correctable with proper size pushrods? The rockers I have are comp ultra golds 1.6 ratio.

SonicBlueFiveSlow

Had the studs cut down to .600 (leaves about .480 exposed with the guide plate), used a bottom tap and they still don't ****ing go down all the way...I really don't know what the hell is going on, but I am getting frustrated beyond belief.

SonicBlueFiveSlow

Sure wish I had a pair of stock heads to compare to, but they look awful short to me.

SonicBlueFiveSlow

130 views and no feedback? Wow

projectresto83

What did the machine shop say about it? Are they bottoming out at the same spot since you cut them down? have you tried putting on a couple rockers to see where they sit on the valve tip?