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-   -   454 hp and torque (https://www.offshoreonly.com/forums/do-yourself-boating-budget/322018-454-hp-torque.html)

sutphen 30 01-14-2015 09:18 AM

tq should come in around 500,maybe even alittle more.

92nsx 01-14-2015 10:59 AM

:food-smiley-007:

1BIGJIM 01-14-2015 11:47 AM

Nobody has asked one important question,, what exhaust is he running!

sutphen 30 01-14-2015 11:59 AM


Originally Posted by 1BIGJIM (Post 4249505)
Nobody has asked one important question,, what exhaust is he running!

doesn't matter,,if it everts,,he changes it out for dry tractor pipes.:D

sutphen 30 01-14-2015 12:19 PM

give an idea what a 454 can do.for some other info,my 454 w/ ovals 9-1 comp,,and a flat tappet 230,236 w/ls110 and wet at tips made 527hp and 2 tq peaks of 517tq,4100 and 5100rpm.

http://www.chevrolet.com/performance...ck-454-ho.html

dereknkathy 01-14-2015 01:12 PM

You lose a lot with the low compression. You can get the edelbrock alum heads shaved down to 100cc chambers. That is where you need to be with flat pistons to get to 9 to 1. I am trying a set of L29 heads. Cammed right decent exhaust i am expecting around 400 or so.

apollard 01-14-2015 01:52 PM


Originally Posted by hammerdown500 (Post 4249167)
89 octane. Was told the 781 were 114 cc chambers

Not likely. I've cc'ed several 781 sets and never found one that was under 121 on any chamber. I managed to cut some to 118, but that was running close to getting the deck too thin. 114 would require chambers cast very small and huge deck cutting IMO.

SB 01-14-2015 02:33 PM


Originally Posted by SB (Post 4249150)
No dome on a 454 and open chamber heads = what happened with the parts selection process ?

Or, does he only have 82 octane available near him ?


Originally Posted by hammerdown500 (Post 4249167)
89 octane. Was told the 781 were 114 cc chambers

You missed the seriousness in the joke, including the joke.

CDShack 01-14-2015 04:55 PM

The chart I have says a 781 casting is 118cc open chamber, so I looked online and one had it at 118cc, two had it at 113cc. All I've ever seen were big, at least 118.
I like the 049 castings as well. Probably the two best BBC big oval port heads GM produced.

I would say horsepower is in the 475 range (adjusted) and around 500tq give or take.

dereknkathy 01-14-2015 05:26 PM

049 and 781 have the rep as the 2 best oval open castings. the closed bathtub heads with small chambers are very scarce and time you finish unshrouding the valves, they are back over 110 anyway. that is why virtually all perf big blocks have domed pistons.


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