What heads?
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Fleet Mechanic
Joined: Oct 2005
Posts: 1,369
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From: Gainesville, GA
What heads?
I have a 68 F250 that I installed a 460 from a 75 Lincoln many years ago(1981). I think the compression ratio is about 7:1. Are there any stock iron, inexpensive heads I can use that will up the compression? Thanks.
Senior User
Joined: Dec 2008
Posts: 485
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From: Fowlerville, Michigan
If your 460 popped out of a 75 Lincoln, odds are it already has the inexpensive cast iron heads that were used in truck applications 73-79, which are good, stout heads. You should post the casting number - look on either head right above the exhaust manifold, above the center head bolt.
If the motor's in good shape it should have 8:1-8.5:1 compression. A good, cheap way to up the compression a little and pick up some torque is to buy a good roller timing set with an indexed crank sprocket ($40-$100). Ford retarded the cam by 8deg. to meet emissions standards without having to add a smog pump, and really botched stock performance potential. Most aftermarket indexed crank sprockets give you a 4deg. retard, 0deg., or 4deg. advance. Advancing cam timing takes away a little top end but gives you more low end plus can show 10-30p.s.i. more on a compression test.
If the motor's in good shape it should have 8:1-8.5:1 compression. A good, cheap way to up the compression a little and pick up some torque is to buy a good roller timing set with an indexed crank sprocket ($40-$100). Ford retarded the cam by 8deg. to meet emissions standards without having to add a smog pump, and really botched stock performance potential. Most aftermarket indexed crank sprockets give you a 4deg. retard, 0deg., or 4deg. advance. Advancing cam timing takes away a little top end but gives you more low end plus can show 10-30p.s.i. more on a compression test.
Thread Starter
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Fleet Mechanic
Joined: Oct 2005
Posts: 1,369
Likes: 7
From: Gainesville, GA
It's been rebuilt once a while back, about 1988, with the right timing gears, an RV cam and a small Holley I took off the 390 it replaced. I know the compression ratio is less than stock because of the sunken valves from the rebuilder. Without putting larger valves, or new seats in the existing heads I'd like to start over with a higher compression set if someone knows the numbers. Thanks.
Elder User
Joined: Jun 2004
Posts: 800
Likes: 6
From: Edmonton, Alberta Canada
look for the early small chambered heads. they will raise the compression approx 1 pt over stock.
the casting numbers tolook for are D0VE, C9VE or C8VE. they are basically all the same head so you can mix and match. found on 71 and older cars.
one thing to remember doing this swap is that you will probably need different pushrods. the factory pushrods probably probably won't be the right lenght as they changed the deck height on the blocks and the valves and rocker arms are totally different from each other. you will have to bolt everything up then make a adjustable pushrod to get the proper lenght and geometry and then order some new pushrods.
rgds
Mike
the casting numbers tolook for are D0VE, C9VE or C8VE. they are basically all the same head so you can mix and match. found on 71 and older cars.
one thing to remember doing this swap is that you will probably need different pushrods. the factory pushrods probably probably won't be the right lenght as they changed the deck height on the blocks and the valves and rocker arms are totally different from each other. you will have to bolt everything up then make a adjustable pushrod to get the proper lenght and geometry and then order some new pushrods.
rgds
Mike
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