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Discussion Starter #1
i',ve got a Chevy 402 short block out of a 71 truck. 2 bolt mains, steel crank. I'm thinking of throwing a set of 990 heads (once i find a decent set) on it and trying to make roughly 500 or so horses. i figure if i keep it under 6500 rpm's it'll stay together. does anyone have any info or advice on this?
maybe something i should know before i attempt to run this block.
any info would be appreciated.
it's going in a first run XH511. 12 degree Casale with 15 gears.
thanks.
 

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i',ve got a Chevy 402 short block out of a 71 truck. 2 bolt mains, steel crank. I'm thinking of throwing a set of 990 heads (once i find a decent set) on it and trying to make roughly 500 or so horses. i figure if i keep it under 6500 rpm's it'll stay together. does anyone have any info or advice on this?
maybe something i should know before i attempt to run this block.
any info would be appreciated.
it's going in a first run XH511. 12 degree Casale with 15 gears.
thanks.
396/402 are fine in a boat - cruising rivers and a little jet boat action . build it with a blower and a set of ls6 rods a steel crank and a decent valve train and you will have years of fun .

Do take the time to go threw the oiling system . I think early blocks had the groved rear cam bearing - this can be a issue !
 

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steelcomp was here
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i',ve got a Chevy 402 short block out of a 71 truck. 2 bolt mains, steel crank. I'm thinking of throwing a set of 990 heads (once i find a decent set) on it and trying to make roughly 500 or so horses. i figure if i keep it under 6500 rpm's it'll stay together. does anyone have any info or advice on this?
maybe something i should know before i attempt to run this block.
any info would be appreciated.
it's going in a first run XH511. 12 degree Casale with 15 gears.
thanks.
Before you spend $$ on a set of 990's, you might want to look at these. The 990's will make that 402 pretty lazy under 6500.

http://www.performanceboats.com//showthread.php?t=20842
 

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Do take the time to go threw the oiling system . I think early blocks had the groved rear cam bearing - this can be a issue !
That is correct, on a 65, maybe 66 block, but the 1971 factory 402 should be fine.

I have a nice set of 990's for sale, but agree that you are probably better off with 049's.
 

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steelcomp was here
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That is correct, on a 65, maybe 66 block, but the 1971 factory 402 should be fine.

I have a nice set of 990's for sale, but agree that you are probably better off with 049's.
Dang it... Sorry Barry...didn't mean to step on toes...
 

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Discussion Starter #7
well what i f i was running say 12.5 to 1 comp. a big solid cam and a tunnel ram with two 750's?
 

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Dang it... Sorry Barry...didn't mean to step on toes...
You didn't in the least Scott, I was giving him a push towards a set of yours actually.

well what i f i was running say 12.5 to 1 comp. a big solid cam and a tunnel ram with two 750's?
If you are going to try and turn higher rpms,, as previously stated, perhaps over 6500 the larger heads might work a little better.
 

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well what i f i was running say 12.5 to 1 comp. a big solid cam and a tunnel ram with two 750's?
it will be fine - just buy race gas . and rev the piss out of it , When it gets mad at you . YOU will know it ;)
 
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