double hump heads-1.94 or 2.02 identification
relic7680
06-10-2007, 07:34 PM
i have a set of #3890462 double hump sbc heads dated sep '66. they are 64cc/straight plug/no accessory holes. my casting # book gives 3 different applications as follows:
327 66-68 PASS/CAMARO/NOVA/CHEVELLE 4BC Q-JET 275 HP
327 67 CORVETTE 300,350 HP
302 67 CAMARO Z28 HI PERF
now does the date code on the heads correspond w/ the year of the car or does the year info in the book mean that my heads are definitely from a 275hp engine? and short of measuring the valves with a dial caliper, how do i determine if mine are the desirable 2.02" intake heads? any help would be greatly appreciated.
327 66-68 PASS/CAMARO/NOVA/CHEVELLE 4BC Q-JET 275 HP
327 67 CORVETTE 300,350 HP
302 67 CAMARO Z28 HI PERF
now does the date code on the heads correspond w/ the year of the car or does the year info in the book mean that my heads are definitely from a 275hp engine? and short of measuring the valves with a dial caliper, how do i determine if mine are the desirable 2.02" intake heads? any help would be greatly appreciated.
silicon212
06-10-2007, 07:52 PM
i have a set of #3890462 double hump sbc heads dated sep '66. they are 64cc/straight plug/no accessory holes. my casting # book gives 3 different applications as follows:
327 66-68 PASS/CAMARO/NOVA/CHEVELLE 4BC Q-JET 275 HP
327 67 CORVETTE 300,350 HP
302 67 CAMARO Z28 HI PERF
now does the date code on the heads correspond w/ the year of the car or does the year info in the book mean that my heads are definitely from a 275hp engine? and short of measuring the valves with a dial caliper, how do i determine if mine are the desirable 2.02" intake heads? any help would be greatly appreciated.
In short, you really can't without pulling the heads and looking at the valves. A 9-66 date could mean a 1967 model year.
327 66-68 PASS/CAMARO/NOVA/CHEVELLE 4BC Q-JET 275 HP
327 67 CORVETTE 300,350 HP
302 67 CAMARO Z28 HI PERF
now does the date code on the heads correspond w/ the year of the car or does the year info in the book mean that my heads are definitely from a 275hp engine? and short of measuring the valves with a dial caliper, how do i determine if mine are the desirable 2.02" intake heads? any help would be greatly appreciated.
In short, you really can't without pulling the heads and looking at the valves. A 9-66 date could mean a 1967 model year.
relic7680
06-10-2007, 08:35 PM
heads are not on a motor so i guess i'll just measure...still doesn't guarantee that somebody didn't retrofit the bigger valves if they come out to be 2.02"
silicon212
06-10-2007, 09:26 PM
heads are not on a motor so i guess i'll just measure...still doesn't guarantee that somebody didn't retrofit the bigger valves if they come out to be 2.02"
There is no difference in the castings between 1.94 and 2.02 intakes. You can easily retrofit a set of 1.94s with 2.02s, the biggest thing would be some mild bowl blending and if necessary, unshrouding.
There is no difference in the castings between 1.94 and 2.02 intakes. You can easily retrofit a set of 1.94s with 2.02s, the biggest thing would be some mild bowl blending and if necessary, unshrouding.
relic7680
06-10-2007, 10:41 PM
well the heads look to be pretty untouched (even paint appears to be original) so whatever the valves measure out to is what they probably started as...thanks for the help
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