PV clerance help

89-LX

89-LX

Forum Member
I was wondering if anyone is familiar with checking PV clearance with stud mount rockers? I am switching from the E7TE's to AFR's with stud mount rockers, and I think I am doing something wrong. Exhaust has A LOT of clearance, but the intake "seemed" to be at .050" from what I could measure.

Here is my setup:
-Stock bottom end
-TFS Stage 1 cam
-Trickflow 6.400" hardened pushrods
-FRPP 1.6 stud mount roller rockers
-AFR 165 heads, upgraded springs

I will be coming back into town (Warren/Sterling Heights) on Thursday night, and I was wondering if someone could take a little bit out of the night to give me a hand. I need to get the car running Thursday night or Friday morning to get it out of my brother’s driveway. Any help will be paid with free beer, or another kind of compensation.
 
Gotcha...Ok rule of thumb is .90 for stick...120 for auto. with a steel rod.

.50 is a lil tight...But that depends on how hard you are going to spin the motor...
 
The Big Cheese said:
Gotcha...Ok rule of thumb is .90 for stick...120 for auto. with a steel rod.

.50 is a lil tight...But that depends on how hard you are going to spin the motor...
Click to expand...


It’s a street motor, stock bottom end with stock forged steel rods, running a 5-speed. Max speed will be about 6000 rpm's, but I can bring that down a little bit. It is also a daily driven car in the spring-fall time. A few of my concerns were:

-Using the old head gasket. It’s compressed quite a bit.
-Its my first time with stud mount rockers. I'm used to pedestal where you just bolt them down. I am wondering if I am tightening them down a little too much, and putting preload on the rocker, causing the measurement to go down to a smaller figure.

That why I was wondering if anyone would be interested in helping me out. Once I see how it’s done, I will know it for life. It’s a little more complicated them what I've read online. Like I said, I will compensate anyone who helps me, dinner for you and your wife/gf, beer, anything. I just need to get this car done.
 
Well I love to help but I am clear across the state from ya..
Heres the deal tho..
@TDC and @MAX Cam Lift thats is where you measure PV.
SO if you have pre checked everything.
Mount the rocker on the stud...rotate the motor couple times with clay on piston and measure..do this thur out the motor if you are using custom pistons...custom heads
Again..rule of thumb is 90 for manual 120 for auto..50 is tight but your not going to spin it too high...so you might be ok..
A new head gasket may add a lil depends on brand..but you have to remember also that as you increase gasket you lose compression points..
Not too familar with SBF..maybe someone else on here will say...
 
The Big Cheese said:
Well I love to help but I am clear across the state from ya..
Heres the deal tho..
@TDC and @MAX Cam Lift thats is where you measure PV.
SO if you have pre checked everything.
Mount the rocker on the stud...rotate the motor couple times with clay on piston and measure..do this thur out the motor if you are using custom pistons...custom heads
Again..rule of thumb is 90 for manual 120 for auto..50 is tight but your not going to spin it too high...so you might be ok..
A new head gasket may add a lil depends on brand..but you have to remember also that as you increase gasket you lose compression points..
Not too familar with SBF..maybe someone else on here will say...
Click to expand...

The car is in Warren, at 14 and Schoenherr.
 
Hopefully some of the Ford guys will get on here help you out..388monte(Mike) is a rep for Diamond Pistons if he gets back to ya he should know...I would say 50 is tight..but again your not spinning it so..
 
The Big Cheese said:
Hopefully some of the Ford guys will get on here help you out..388monte(Mike) is a rep for Diamond Pistons if he gets back to ya he should know...I would say 50 is tight..but again your not spinning it so..
Click to expand...

I appreciate the help. Any help right now is what I need.
 
That does seem awfully tight for those heads and that cam. Cheese is correct though. If that .050" is correct I wouldnt run that. If you float a valve its gonna hit and do damage. You have the valve geometry correct? How are you adjusting the valves with the solid roller? I am close to warren and *MIGHT* be able to help. Hard to tell what my days are like with the kids and the wife.
 
orangejuiced86 said:
That does seem awfully tight for those heads and that cam. Cheese is correct though. If that .050" is correct I wouldnt run that. If you float a valve its gonna hit and do damage. You have the valve geometry correct? How are you adjusting the valves with the solid roller? I am close to warren and *MIGHT* be able to help. Hard to tell what my days are like with the kids and the wife.
Click to expand...
Thanks for jumping in Ryan....
 
orangejuiced86 said:
That does seem awfully tight for those heads and that cam. Cheese is correct though. If that .050" is correct I wouldnt run that. If you float a valve its gonna hit and do damage. You have the valve geometry correct? How are you adjusting the valves with the solid roller? I am close to warren and *MIGHT* be able to help. Hard to tell what my days are like with the kids and the wife.
Click to expand...

Not too sure about valvetrain geometry. Like I said, this is pretty much new to me. I'm used to pedestal mount rockers and stock heads, but I want to learn with these. If you could help for about 1-2 hours at most, it would be a HUGE help. Even less than an hr just to show me and double check to see I am doing it right.

But pretty much, I am twisting the pushrod and tightening the rocker down till I cant switch the pushrod anymore, then I lock the lifter there and check the clearance.
 
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