Trying to figure out whether I need 5/16, 3/8, or 7/16 stud size for Roller Rockers on GT40P heads. Been digging through old forums before I came here but I can't find a clear answer. Thanks.
Engine Roller Rocker Stud Size, GT40P heads
- Thread starter foxbodyclark
- Start date
85GTStangGuy
5 Year Member
89ripper
Founding Member
Your going to put alot of money into these heads doing this.... I would opt for different rockers or get some aluminum heads that will not require all of this machine work that will contribute NOTHING to any performance gain..
I used some roller tip rockers on my " P " heads as I was going to change out my rockers not knowing how many quadzillion times they had gone up and down in their lives..... My reasoning is the roller tip helps prevent " sideways push" on the valves contributing to bore wear....
I used some roller tip rockers on my " P " heads as I was going to change out my rockers not knowing how many quadzillion times they had gone up and down in their lives..... My reasoning is the roller tip helps prevent " sideways push" on the valves contributing to bore wear....
What rockers would you suggest? This topic is a bit out of my wheelhouse so I may have gotten terminology wrong.Your going to put alot of money into these heads doing this.... I would opt for different rockers or get some aluminum heads that will not require all of this machine work that will contribute NOTHING to any performance gain..
I used some roller tip rockers on my " P " heads as I was going to change out my rockers not knowing how many quadzillion times they had gone up and down in their lives..... My reasoning is the roller tip helps prevent " sideways push" on the valves contributing to bore wear....
I am not the guy to ask about " which ones are best" ... I did what would work best for what I wanted.....
You don't have many options for bolt on except pedestal mount without spending alot on machine work " as far as I know"...
If you go down the path of alot of Hi Po parts on your stock P head, you will have more money into your P heads tham a nice set of aftermarket Aluminum heads that will perform better....
You don't have many options for bolt on except pedestal mount without spending alot on machine work " as far as I know"...
If you go down the path of alot of Hi Po parts on your stock P head, you will have more money into your P heads tham a nice set of aftermarket Aluminum heads that will perform better....
You can run full roller rockets, roller tip rockers (not sure they are available anymore), or stock ones. How much wallet do you have and is 10 to 15 hp worth it?
Question: Aside from the cost of the roller rockers, what else has to be done to accommodate them on an otherwise, stock GT40 head?
Blackhawkxx
Advanced Member
- Mar 3, 2023
- 457
- 455
- 73
If the heads are pedestal mount, the Scorpions are nice and you can stay with 1.6 or go 1.72 like I did on my 85 GT when I had it.
Put the stock rockers back on it... Your just throwing money away with anything else..
If it were me, I'd probably go this direction but then I plan boost for just about everything I own.
Crane used to make a pedestal to stud mount conversion kit. I had the kit at one time, but never used it and gave it to a friend.
Pretty sure this was it. https://www.summitracing.com/int/parts/crn-35655-16
Just buy a set of for racing or crane 1.6 or 1.7 pedestal rockers on facebook and shim them as necessary.
No chance I'm going past a valve job on gt40 iron anything, the money just doesn't make sense.
I had not seen that article listed above and while informative that's like $800 in parts and that doesn't include labor. Not to mention that is 2014 money.
You can buy afr enforcers for just a few more dollars.
Pretty sure this was it. https://www.summitracing.com/int/parts/crn-35655-16
Just buy a set of for racing or crane 1.6 or 1.7 pedestal rockers on facebook and shim them as necessary.
No chance I'm going past a valve job on gt40 iron anything, the money just doesn't make sense.
I had not seen that article listed above and while informative that's like $800 in parts and that doesn't include labor. Not to mention that is 2014 money.
You can buy afr enforcers for just a few more dollars.
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