FORD RACING ROLLER ROCKERS

...I would be more concerned with the bolt diameter!! At 5/16", how many revs do you think they will take before it snaps off at the threads? I went to roller rockers; but did it the 'Right' way and machined the pedestals down and drilled and tapped for 7/16" Chrome-Moly Studs (Morroso) with their smooth shoulders and Large Fillets, Near 'Bullet Proof'!! I see NO need for stud girdles...

You need to stay close to stock with the spring rates. The bolt and the pedestal are more vulnerable to failure as you up the spring rates.

I don't know where the danger level is spring rate wise but lets just say they are for a 6,000rpm engine.

You may need to adjust the "bolt downs" with the shims provided. Especially if you are cutting the valves.

They are a good way to go for the average enthusiast.

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with the shims provided

Shims are another part number and are NOT included, but I have them ready and waiting if lifter preload comes out too tight.

Larry - average enthusiast? Most folks who know me would surely not describe me as average

I ran the Crane Cams conversion kit on my last set of heads before putting on the aluminum ones and never had a problem. No machining, and included pushrod guides. I agree with Marlin though, the way to go is to machine the heads and use quality stuff in such a critical area.

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No machining, and included pushrod guides.

But with the guides, didn't you also have to upgrade to hardened push rods?

The Ford Racing conversion requires nothing new other than the rocker conversion.

And isn't the Crane kit an adjustable system, requiring more 'thinking' for installation?

Larry

The guides have a plastic insert so hardened pushrods not required. You are correct in that you do need to adjust the preload.
Forest

Larry, you purchased some good rockers, I'ved used them on my own Mustangs, and installed them in cars belonging to others, no failures. Ford has sold them for decades. I believe they're actually Crane rocker arms, just anodized blue instead of gold. Anyway, they're billet, not cast, good stuff. These are the rocker arms I am always recommending others to install. Those rockers and their allen head cap screw will easily "clamp" the spring pressures of the springs specified with ANY hydraulic cam, without worry. You see Ford hires these guys called engineers, and they do stuff like specifying bolts. The thinking goes like this: Non-adjustable rocker arms.....hydraulic cams.....lower spring rates....5/16" cap screw. Adjustable rocker arms ... solid lifter cams...higher spring rates...7/16" studs.

There's 2 considerations: the threads of the bolt/stud pulling out of the head, and side forces flexing the bolt/stud. The 5/16" threads have proven over the years they do not pull out of the heads in applications with hydraulic cams. With the mondo spring pressures encountered with some solid cams, yes the 7/16" threads are required. Side forces with the adjustable rocker system are applied directly to the stud, thats why that nice big radius is required at its base. BUT side forces with your rockers are applied to the pedestal, NOT the 5/16" bolt. The pedestal is plenty beefy. All the bolt has to do is keep the assembly clamped together and not pull out of the threaded boss in the head.

The shims mentioned are to raise the rocker arm to achieve correct geometry, they go between the rocker pedestal and the slot in the head. When all is said and done, you may need new push rods, you won't know until your heads are back and mounted on the motor, the rockers are all set for best geometry.

Anyway, the stock rocker arms are junk, and you have purchased the correct replacement.

That's great advice about how to save $70 bucks, very nice of you to share that.

I had a set of these rockers on my 4V closed chamber heads. The problem that I had was that I ended up having to buy adjustable push rods to get the valve lash adjusted correctly. Once they were set up, I never had any problems and put at least 50k miles on them. They were taken off last year when I upgraded to CHI aluminum heads, which had screw in studs.

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I had a set of these rockers on my 4V closed chamber heads. The problem that I had was that I ended up having to buy adjustable push rods to get the valve lash adjusted correctly. Once they were set up, I never had any problems and put at least 50k miles on them. They were taken off last year when I upgraded to CHI aluminum heads, which had screw in studs.

Valve lash? Sounds like you were using solid lifters. This specific kit is designed for hydraulic lifters only.

Now these rockers - just the rockers - are also used with the stud (7/16") conversion. Is this what you had? I can understand a push rod length issue with solid lifters.

I'm confused by your post - can you clarify?

Thanks,

Larry

You won't need new pushrods. You are cutting the valves. You may need to shim .010" though.
Don't worry about it now. It's no big deal.

What difference can I expect with these rockers on 4V heads and "3/4 race cam" (that’s what the previous owner called it)?
I have stock rockers installed now.

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Originally posted by LF - TP 2511:

quote:

I had a set of these rockers on my 4V closed chamber heads. The problem that I had was that I ended up having to buy adjustable push rods to get the valve lash adjusted correctly. Once they were set up, I never had any problems and put at least 50k miles on them. They were taken off last year when I upgraded to CHI aluminum heads, which had screw in studs.

Valve lash? Sounds like you were using solid lifters. This specific kit is designed for hydraulic lifters only.

Now these rockers - just the rockers - are also used with the stud (7/16") conversion. Is this what you had? I can understand a push rod length issue with solid lifters.

I'm confused by your post - can you clarify?

I have a hydraulic lifter cam, but with the piston on TDC and with both valves closed, the rockers were too loose. I know that with a hydraulic set up, you just tighten it down, but it didn't work for me with these rockers. It could have been my spring set up. They might work fine for your set up, but they didn't for mine without the adjustable push rods.

Thanks,

Larry

Finished the roller rocker install this past weekend - tedious and time consuming, but not difficult. To call them "bolt in" is a bit optimistic.

Haven't driven yet, but motor starts, makes no funny noise and leaks no fluids. Some tune up work, install a bunch of pieces still on the floor and workbench, and go for a drive tomorrow or Friday, time permitting.

Larry