head question
Butt-Head
Joined: Apr 2004
Posts: 9,411
Likes: 2,899
From: Reed Point, MT
Just about any head can be used on a mild build. These heads have the Olympic-size swimming pool chambers (about 97 CC), non-adjustable rocker arms (a plus in my book), and roughly the same sized intake ports and valves/exhaust ports and valves as other non-performance 385 series heads.
You will find that albeit harder to get decent compression (above 9.5:1/below 10:1...it takes a special piston), it's worth it in the long run to have the open chamber heads. They are more efficient and are less detonation-prone than closed chamber heads. Also, with the non-adjustable rockers, it's a bolt it on and play affair....set it and forget it (you just can't too wild with the camshaft).
Also, be aware of the block you are using. 68-70/10.3" Deck, 71/10.310" deck, 72-up/10.322" deck. These will also make a difference in compression (not a lot, but could be the difference in a 'dog' or 'detonation hound').
My suggestion is to find a 68-71 block and use your D3 heads.
Cody
You will find that albeit harder to get decent compression (above 9.5:1/below 10:1...it takes a special piston), it's worth it in the long run to have the open chamber heads. They are more efficient and are less detonation-prone than closed chamber heads. Also, with the non-adjustable rockers, it's a bolt it on and play affair....set it and forget it (you just can't too wild with the camshaft).
Also, be aware of the block you are using. 68-70/10.3" Deck, 71/10.310" deck, 72-up/10.322" deck. These will also make a difference in compression (not a lot, but could be the difference in a 'dog' or 'detonation hound').
My suggestion is to find a 68-71 block and use your D3 heads.
Cody
Posting Guru
Joined: Jun 1999
Posts: 2,404
Likes: 1
From: Everett, Wa
Just some corrections to make. All 460, non EFI heads are closed chamber except the D2VE head. Stay away from that head. It is an open chamber design, is detonation prone regardless of compression and you can not make the head flow regardless of what you do.
The only differnece between the 71 and earlier and 73 and later is the size of the combustion chamber. These heads are closed chamber with the only difference being the size of the combustion chamber. Both heads can be modified for adjustable rockers and can be ported to flow well for a iron head. The later heads will allow more choices when it comes to compression ratios.
I would also get a 72 or later block. The reason for this is so you have room to square the block up. With the early blocks you can not deck them in most cases to truely square them up. You want to run zero deck hieght regardless of the compression ratio you end up running and the later blocks will allow you to machine a nice square block.
The only differnece between the 71 and earlier and 73 and later is the size of the combustion chamber. These heads are closed chamber with the only difference being the size of the combustion chamber. Both heads can be modified for adjustable rockers and can be ported to flow well for a iron head. The later heads will allow more choices when it comes to compression ratios.
I would also get a 72 or later block. The reason for this is so you have room to square the block up. With the early blocks you can not deck them in most cases to truely square them up. You want to run zero deck hieght regardless of the compression ratio you end up running and the later blocks will allow you to machine a nice square block.
