[1970]: Help, mismatched cylinder heads: 3998920 & 3986336
07-17-2003, 10:17 PM
#1
Team Owner
Thread Starter
[1970]: Help, mismatched cylinder heads: 3998920 & 3986336
Can some of you please check out this thread? A friend's vette has mismatched heads.
http://forums.corvetteforum.com/zerothread?id=607440
http://forums.corvetteforum.com/zerothread?id=607440
07-17-2003, 10:47 PM
#2
Le Mans Master
Re: [1970]: Help, mismatched cylinder heads: 3998920 & 3986336 (scorp508)
scorp im gone to say there 76cc since world products heads says there torquers heads are 76cc and they have that number as a direct replacement.
07-18-2003, 12:59 AM
#3
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Re: [1970]: Help, mismatched cylinder heads: 3998920 & 3986336 (patsnitrovette)
The LT-1 heads in 70 were 68cc resulting in 11:1 compression (2.02/1.60 valves). The 71 LT-1 heads were 78cc to reduce compression. I would guess the base motor in 70 was also 78cc. Don't know about the 350/350 in 70. What is the motor?
07-18-2003, 11:43 AM
#4
Drifting
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Re: [1970]: Help, mismatched cylinder heads: 3998920 & 3986336 (scorp508)
1970 LT-1 heads were 68cc with 2.02 intake (With Push Rod Guides)
1970 350/350 were basically the same head as LT-1 (With NO Push rod guide)
1970 350/300 were 68cc with 1.94 intake valves, no guides.
1970 LT-1 & 350/350 used domed pistons = 11:1 Compression
1970 350/300 used flat top pistons = 10.25:1 Compression
1970 350/350 were basically the same head as LT-1 (With NO Push rod guide)
1970 350/300 were 68cc with 1.94 intake valves, no guides.
1970 LT-1 & 350/350 used domed pistons = 11:1 Compression
1970 350/300 used flat top pistons = 10.25:1 Compression
07-18-2003, 04:48 PM
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Re: [1970]: Help, mismatched cylinder heads: 3998920 & 3986336 (Barry's70LT1)
Corvette Black Book lists three heads used for the 70 350: part # 3927186, 3927187, & 3973414 186's were used on all combos, while the 187's were used only on the 350HP version. 3973414 heads were used only on the 370HP version. Hope this helps.... :cheers:
