Stroked 400
Posting Guru
Joined: Aug 2000
Posts: 1,127
Likes: 3
From: (near) Denver USA
In another venture far afield from the original topic of this thread, I'll add a few tidbits.
Most of the detonation problems in the 400 were a result of the engine's original design flaw, excessive compression with the open-chamber 351C 2V cylinder heads and 351C 2V pistons.
To solve this problem, the 400 piston was allowed to sit lower in the cylinder at TDC (giving more deck clearance), and early 400 heads were made with a slightly larger chamber than the 351C 2V heads. With the higher octane leaded fuels that were available in 1970-71, these compromises were adequate.
When unleaded fuel (with lower octane) was mandated nationwide in the US in MY1975, the 400's original design flaw came back to haunt it mercilessly. In their desperation to solve the problem, Ford resorted to severe ignition timing retard and dished pistons that dropped the 400's static compression all the way down to 7.33:1.
The changes made to the 400's tuning specifically for emissions were not unique to that engine. Ford retarded camshaft timing and lowered compression across the board, in all of their engines by MY1973.
A lot of 302 and 351W blocks and other components were cast at the Cleveland Foundry.
From 1967 to 2000, Cleveland Engine Plant No. 1 produced over 16.9 million 302/5.0 engines. From 1969 to 1981, Cleveland Engine Plant No. 2 produced 3.7 million 351C and 351M engines. From 1969 to 1997, the Windsor Engine Plant produced a little less than 8.5 million 351W engines (out of a total of over 20 million V8 engines).
From MY1975 to MY1979, the 351M and 351W were used interchangeably in most of the mid-sized and full-sized car lines.
Right now, the Lima Engine Plant produces 3.0 V6s used in Taurus/Sable cars and Ranger pickups, and the 3.9 V8 used in the Lincoln LS and Thunderbird.
Most of the detonation problems in the 400 were a result of the engine's original design flaw, excessive compression with the open-chamber 351C 2V cylinder heads and 351C 2V pistons.
To solve this problem, the 400 piston was allowed to sit lower in the cylinder at TDC (giving more deck clearance), and early 400 heads were made with a slightly larger chamber than the 351C 2V heads. With the higher octane leaded fuels that were available in 1970-71, these compromises were adequate.
When unleaded fuel (with lower octane) was mandated nationwide in the US in MY1975, the 400's original design flaw came back to haunt it mercilessly. In their desperation to solve the problem, Ford resorted to severe ignition timing retard and dished pistons that dropped the 400's static compression all the way down to 7.33:1.
The changes made to the 400's tuning specifically for emissions were not unique to that engine. Ford retarded camshaft timing and lowered compression across the board, in all of their engines by MY1973.
A lot of 302 and 351W blocks and other components were cast at the Cleveland Foundry.
From 1967 to 2000, Cleveland Engine Plant No. 1 produced over 16.9 million 302/5.0 engines. From 1969 to 1981, Cleveland Engine Plant No. 2 produced 3.7 million 351C and 351M engines. From 1969 to 1997, the Windsor Engine Plant produced a little less than 8.5 million 351W engines (out of a total of over 20 million V8 engines).
From MY1975 to MY1979, the 351M and 351W were used interchangeably in most of the mid-sized and full-sized car lines.
Right now, the Lima Engine Plant produces 3.0 V6s used in Taurus/Sable cars and Ranger pickups, and the 3.9 V8 used in the Lincoln LS and Thunderbird.
Freshman User
Joined: Dec 2003
Posts: 30
Likes: 0
From: Great White North
Battered_Bronco, of course your right: running a dual pattern cam on any 335 is a great idea, you could get a cheapo single pattern and run it with worse results......
Good for you folks for knowing so much Ford history! You are most helpful in planning future projects...
Good for you folks for knowing so much Ford history! You are most helpful in planning future projects...
Elder User
Joined: Apr 2003
Posts: 821
Likes: 0
From: Normal, IL
Check out Isky's website, and go to tech. Read through the tech tips series, very interesting. If you can pick up power by increasing exh. duration, think what you could do with an increase in int. duration. Can you spell "screamer"?
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yankeerebel
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