I was wondering what stock rocker arm ratio, and the stud size, is on my 400m. I was thinking on getting some roller rockers over the internet while im at college for the week and I'm not able to measure my heads. The heads are stock on the engine. Your help would be greatly appreciated. Thanks.

 

The heads are pedistal mounts too, I was planning on sonverting them to studs by buying a stud kit. Is this a good idea.

 

i'm running pedestal-mount scorpion roller rockers from tmeyerinc.com.
they match stock ration of 1.73 and bolt right on stock heads AND fit under stock valve covers...

 

Thanks did you convert from pedistal to stud mounts too.

 

The Scorpion roller rockers are pedestal mount - you still run them with the square pedestal that mounts in the recess on your heads. No machining required. Ford Racing also makes a pedestal mount roller rocker for that head.


If you want to run adjustable stud-type rockers, you will have to have your heads machined to accept 7/16" studs. That requires machining off the "ears" of the pedestals, so the top of the threaded boss is flush across the top. You won't be able to go back to the OEM pedestal mount rockers without replacing the heads. Any shop that rebuilds heads should be able to do it for you for $80-150 bucks.

Stud kits don't get glowing reviews. Even Crane says their stud conversion kit isn't for performance use. If you want to run an adjustable valvetrain, definitely go with the stud mount rockers.

Stock ratio is 1.73

 

Where could you get these, how much do they cost?

 

We sell the Scorpions for $239.

They have a life time warranty on them also.

course they consider 5 years a the life of them

 

Does Ford Racing make thier own, or do they all come from the same manufacturer?

 

The Fords sell for about $375 a set. I don't know who makes theirs.

 

What size are the studs/bolts?

 

On the scorpion kit

 

5/16 bolts like the Fords also. That is your existing thread.

 

Alright thanks for the help.

 

Do these fit on the aussie heads also? is this the same?
Another q to hijack this thread: does anybody know if the aussie heads have standard size valves, and if so, what the size of these valves are?
I'm thinking of using these scorpions with new ferrea stainless valves and hardened seats..

 

Aussies are same as U.S. 2V heads, except smaller, closed combustion chamber design. Same rocker setup, same 2V valve size.