BHP estimates please
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BHP estimates please
My mates nearly finished putting together his latest engine set up and i was wondering what bhp he should be expecting.
Its a 440 Mopar with a mild roller cam, roller rockers, CR is down to 9:1 and hes slapped a slightly underdriven 8/71 blower with 2 x 750 (IIRC) carbs on top.
Its a 440 Mopar with a mild roller cam, roller rockers, CR is down to 9:1 and hes slapped a slightly underdriven 8/71 blower with 2 x 750 (IIRC) carbs on top.
10.612 @ 129.77
176.5 standing mile.
176.5 standing mile.
Hi
He would pick a mopar! the only big block that has heads that range from terrible to not all that bad from the factory. I think they rated factory output from about 175 bhp to 390 odd depending on cam and heads with most ratings between 225 and 335 so really you need to find out what the original output of the engine those heads came from. If it is under driven by about 20% and the heads came off an engine rated at 335 bhp, you would probably see about 550 to 650 bhp, if they were off a 175 bhp engine and the same underdrive you would probably see 350-375 shortly before it all went bang.
This engine does not like to rev so it is all about head flow to get it to make power.
Best regards
Mike
He would pick a mopar! the only big block that has heads that range from terrible to not all that bad from the factory. I think they rated factory output from about 175 bhp to 390 odd depending on cam and heads with most ratings between 225 and 335 so really you need to find out what the original output of the engine those heads came from. If it is under driven by about 20% and the heads came off an engine rated at 335 bhp, you would probably see about 550 to 650 bhp, if they were off a 175 bhp engine and the same underdrive you would probably see 350-375 shortly before it all went bang.
This engine does not like to rev so it is all about head flow to get it to make power.
Best regards
Mike
poppet valves rule!
Hi
OK I stand corrected, just every article I have read on this engine (and I have read quite a few as I was thinking of building one once) recons it won't rev beyond about 5500 on standard crank and rods without going bang. Quite a bit more on a forged lightweight crank using BBC rods and journal sizes but they said the standard items were to big and heavy and tended to crack the block if reved.
Bestr egards
Mike
OK I stand corrected, just every article I have read on this engine (and I have read quite a few as I was thinking of building one once) recons it won't rev beyond about 5500 on standard crank and rods without going bang. Quite a bit more on a forged lightweight crank using BBC rods and journal sizes but they said the standard items were to big and heavy and tended to crack the block if reved.
Bestr egards
Mike
poppet valves rule!
I forgot i started this
Tonys back home now and finishing off the install of the blower.
To add.... previously it put 300bhp @ wheels on John Sleaths rollers at modest rpm but had more to give.
The Interceptor is in full street trim and has run 12.5 over the 1/4 on the NA set up. A pair of small MT street radials, a trick box and a moderate stall converter all help a little too.
Hes hoping for 600+, I think he may get more. A fully street trimmed Jensen will soon be running mid 11's I think. Then hes got the gas to play with. It had 400 @ the wheels on a 125 shot.
Tonys back home now and finishing off the install of the blower.
To add.... previously it put 300bhp @ wheels on John Sleaths rollers at modest rpm but had more to give.
The Interceptor is in full street trim and has run 12.5 over the 1/4 on the NA set up. A pair of small MT street radials, a trick box and a moderate stall converter all help a little too.
Hes hoping for 600+, I think he may get more. A fully street trimmed Jensen will soon be running mid 11's I think. Then hes got the gas to play with. It had 400 @ the wheels on a 125 shot.
10.612 @ 129.77
176.5 standing mile.
176.5 standing mile.
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The owners club will snub him to death! We could be twins
You can calculate the worth of a man by the number of his enemies, and the importance of a work of (automotive) art by the harm that is spoken of it.
Gustave Flaubert, Letter to Madame Louise Colet (June 14 1853).
You can calculate the worth of a man by the number of his enemies, and the importance of a work of (automotive) art by the harm that is spoken of it.
Gustave Flaubert, Letter to Madame Louise Colet (June 14 1853).
It's an engine Jim.....but not as we know it