351W head ?s

[blueovalguy]

I've got a 351W, bored .30 over, Edelbrock Performer RPM cam, intake and carb, Accudrive gear drive, Crane springs, Comp Cams roller rockers + a bunch of other ****. At what point do you need to change from press-in studs to screw-in studs on the heads? Also, what does it cost to have them drilled and tapped for the screw in studs? I've also heard that they need to machine some off the "pedestal" where the studs screw in due to the height of the "head" of the screws. Is this true?

 

[Max Power]

Depends on what cam and springs you are running.

It's not that expensive, and any good machine will know what to do.

The real expense will be getting decent springs, installing hardened seats and doing a valve job with porting. Not much point in taking the heads off just for studs.

 

[blueovalguy]

Depends on what cam and springs you are running.

It's not that expensive, and any good machine will know what to do.

The real expense will be getting decent springs, installing hardened seats and doing a valve job with porting. Not much point in taking the heads off just for studs.

I'm running the Edelbrock Performer RPM cam, crane springs/wcomp cams roller rockers. I already have the hardened seats, exhaust bumps are ground off, and valve job done. The guy who did the motor for me said I wouldn't need the screw ins, but since then, everyone I talk to says I need them.

 

[D.Hearne]

You'll only need them when those pressed in studs, start pulling out of the heads with the stiffer springs and higher lift cam. You'll know when they do pull out, you'll start seeing bent pushrods. By the way, how did you adjust those rockers with positive stop Windsor studs?

 

[D.Hearne]

Some of the pedestal needs to be removed to gain clearance for the guide plates, you'll need under the studs. Othewise the rocker fulcrums are going to bottom out on the pedestals

 

[brianj5600]

I have used studs that look like small head studs. I think they are Ersons. They worked with a 600 lift solid and roller tipped rail rockers. I pulled the press ins and tapped the holes. If it aint broke, don't fix it. If a lifter starts tapping, limp it home.

 

[302 coupe]

By the way, how did you adjust those rockers with positive stop Windsor studs?

thats what I was wondering.....maybe he put washers under the nuts to get a little extra adjustment. I made the mistake of trying to adjust rockers on the positive stop studs one time, but the nuts always bottomed out before the rockers were tight enough.

 

[blueovalguy]

You'll only need them when those pressed in studs, start pulling out of the heads with the stiffer springs and higher lift cam. You'll know when they do pull out, you'll start seeing bent pushrods. By the way, how did you adjust those rockers with positive stop Windsor studs?

Now I'm really going to sound stupid, but what do you mean by positive stop studs?
The guy who assembled the motor did everything, and I bought what he suggested!

 

[Max Power]

Positive stop studs are studs that are designed so that you don't have to adjust the rocker arms, you just torque them into place. Really convenient if you have no mods, but if you change anything, they often don't work very well.

I have never seen bent pushrods from studs pulling out, just clattering valvetrain components, which is pretty harmless. Not saying it couldn't happen though.

At this point, if you are not having a problem, I would leave them alone. Too much work to fix and if they start to pull out, it won't ruin anything of value.

 

[D.Hearne]

If they do pull out, you could possibly have a rocker get side ways on the retainer and drop a valve, last time I checked, this is a serious situation, not harmless at all. I've had FE pushrods get loose enough to bend pushrods, and the same thing on a 400M. Small blocks aren't immune to this happening. I think if I were you , I'd find another machine shop for your work. Using pressed in studs with a cam like that, isn't a good idea, anyone who knows Fords, also knows this.

 

[66SilverStar]

yeah you know you've got a problem when the motor is running and you can see the press in studs pulling out. the tapping can cause some problems as far as bending the pushrods or cracking the rocker arm. I've seen both happen personally. its not a good feeling when you just put the motor together and you have to pull the heads back off and spend another $150 on studs, guide plates and machine work. the cam in the motor i built was one of the smallest dual energy cams from comp and their listing said it would work with stock valvetrain. huh so much for that.

Jimmie