Help Please
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Laughing Gas
Joined: Jan 2008
Posts: 758
Likes: 0
From: Alabama
Help Please
Hello. New to the forum. I have come to a point in my rebuild that I am stuck and need your expert advice. Over the years I have done several engine rebuilds but have always went stock on everything. This is my once in a life time rebuild of an old truck and I went to the darkside. I have a 53 F100 that has a 351 windsor motor. The motor was completely worn out. I had a local shop to vat and bore the block. Then I replaced everything. It now has a comp cam with a .500 lift and duration @ .050 Intake and exhaust .224. Lobe lift is .313. Lobe seperation is 110.0. The heads are stock cast heads that had flat tappet rockers. I replaced the valves with stainless valves and .550 springs. Now for my question, I am stuck as to what type rockers to use. I looked at the Summit web site and there are so many types of rockers I'm not sure what is best to use. I see alot of 7/16 and 3/8 stud mounts. The stock rockers were held in place with a 5/16 bolt. Anyone out there that has experience with this and can point me in the right direction? It would be greatly appreciated. Lakota
Cargo Master
Joined: Aug 2004
Posts: 2,575
Likes: 36
From: Greenville, SC
You may want to post this question on the engine forum. https://www.ford-trucks.com/forums/forum55/
Junior User
Joined: Nov 2007
Posts: 67
Likes: 1
From: Azle, Texas
You want pedestal mount type rockers. Your cam specs should tell you what ratio you need, 1.6 or 1.7. You'll also need to get a shim kit for the mounts in order to adjust the valves. About 1/2 turn from zero.
Cargo Master
Joined: Apr 2007
Posts: 2,063
Likes: 38
From: Valley Center, California
Ditto on the Engine Forum.
Even though .500 lift is reasonably tame, if you have press in rocker studs, you should replace them with screw in type. For that application you'd be fine with a stamped roller rocker like Comp Cams sells. Whatever you choose be sure to have the Tech Support folks match your parts up (pushrods etc). It's not wise to mix and match brands unless you really know what you are doing.
Good Luck.
Even though .500 lift is reasonably tame, if you have press in rocker studs, you should replace them with screw in type. For that application you'd be fine with a stamped roller rocker like Comp Cams sells. Whatever you choose be sure to have the Tech Support folks match your parts up (pushrods etc). It's not wise to mix and match brands unless you really know what you are doing.
Good Luck.
Junior User
Joined: Nov 2007
Posts: 67
Likes: 1
From: Azle, Texas
You may not be able to use stock length pushrods if the heads have been milled. If you can't get the proper valve adjustment with stock length pushrods, you'll need to to get a pushrod length checker to determine what length you need to order. Summit sells a Comp Cams pushrod length checker for about $22. I like to check both ends of the heads to determine if the heads are square before ordering pushrods. Summit sells several different lengths by Trick Flow that are not always listed, so you may need to call them.
