-71 429 heads

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Feb 19, 2001 | 01:49 AM

mask

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From: Iggesund SWEDEN

-71 429 heads

Hi, I have a -74 460 and I stumbled over some -71 429 heads
and I wondering if I can put those on without any problems?
What can I expect in comp. rise and horse power
I think its about 8,0 or 8,5:1 now.
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Feb 19, 2001 | 08:40 PM

mavman

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From: arkansas

-71 429 heads

It depends on which heads you have now. Some '74 engines had the large open-chamber heads (95cc), some had interceptor heads (88cc), and most had 92cc, casting #D3VE-A2A. If you have the latter, the new '71 heads with the 72cc chambers will give approximately 9.4 compression...and a huge jump in torque and horsepower. There is virtually no difference in the 460 heads, except the pre-72's used 18mm spark plugs, instead of the smaller 14mm. just check the chamber cc's of the '71 heads...I dont think they made any different ones, but I'm not positive.

Feb 19, 2001 | 09:27 PM

bb79ranch

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-71 429 heads

The'71 429 heads have 75-77cc combustion chambers(base model/passenger car) & the 72cc heads mavman is referring to are the SCJ/CJ/Police heads. The combo you stated will raise compression like mavman has said between 9 to 9.5 to 1 C.R. There are major differences between your '74 heads(either D4VE or D3VE-A2A)and the '68-'71 heads. (A) like mavman said the plug size is larger. (B)429-460 heads from'68-'71 use screw-in studs, the'73 & on used bolts. (C) '68-'71 use valve stem guided rockers(rail rockers) with 1.75 ratio cast iron rocker arms, the'73 & on use pivot guided stamped steel rocker arms and have 1.73 rocker ratio. (D) '68-'71 heads have longer overall length valves and therefore use longer pushrods. (E) '68-'71s don't have the emission "tube" drilled for air pump use, so you can easily port the exhaust to help flow unlike your '73 & after heads. I hope this helps.

Todd
BB79RANCH

Feb 20, 2001 | 01:45 AM

mask

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From: Iggesund SWEDEN

-71 429 heads

ok, Seams like a god idea. I don't now what condition these heads have but he wants 180$ for them. Can I use valves form my 74 in this head or any other parts? If there are in bad shape?
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Feb 20, 2001 | 07:56 PM

hemi

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-71 429 heads

the cj head uses the smaller peanut plug also, because of intake port size. no room for the bigger plug.

Feb 26, 2001 | 03:13 PM

TBirdGuy

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From: Holland, Michigan

-71 429 heads

The 71 heads will be much better because they'll yeild a higher compression and will make more power and torque. You'll probably have bigger valves in the 71', but I'm not sure. A sweet little trick to make it an adjustable valvetrain for the 71' heads that won't cost very much is to buy big block ch*vy Rocker studs and Lock-nuts and install them. Bolt the studs down to about 55 ft. lbs. of torque and you'll have a fully adjustable valve train. Cost will only be like $60.00 bucks and it's a quick easy change.

TBirdGuy

"Stuck with a m*par, Settle for a ch*vy, Happy with a Ford!!!!"