compression

Old 01-06-2012, 07:00 AM
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bear4333
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what's the best compession ratio for a bbc 632 that would make the best power? I'm looking to purchase a short block, my heads are dart 360 cnc.
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Old 01-06-2012, 07:04 AM
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bear4333
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Most of my racing is done at 4800 ft. not ajusted.Average ajust is around 7500 ft.
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Old 01-06-2012, 08:07 AM
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cncmotorsports
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Depends on the gas your going to be using. We typically do 15 or 16:1
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Old 01-06-2012, 09:46 AM
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bear4333
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I currently use 114, I can go up if i need to. my comp now is 14.5 to 1. I wouldn,t mind going hirer if it will produce more power without problems.
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Old 01-06-2012, 12:12 PM
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Who's 114 octane, there is a huge difference between fuels brands. Adding Compression alwasy increases power.
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Old 01-06-2012, 05:24 PM
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The higher the compression, the better the parts need to be.

---
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Old 01-07-2012, 02:46 AM
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I think those heads will be what limits your hp unless they've had some hand work done to them.
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Old 01-07-2012, 09:27 AM
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roadkill2
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Originally Posted by cncmotorsports
Depends on the gas your going to be using. We typically do 15 or 16:1
OK, at the average corrected altitude of 7500 ft. a 15.5/1 comp ratio would work with 116 oct. and 37-8 of lead, what's the hot tip on going to, say Topeka where you're going to be looking at 800 Actual, probably 3700 corrected and twice to three times the water grains? Are we going to have to step down with a thicker head gasket? If so, how thick? I'm under the impression that .060 is our thickest option.

Or do we just bump the timing a couple and suffer on the top end?

Coming from Bear's dumbassed old crew chief . . . .
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Old 01-09-2012, 11:00 AM
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Originally Posted by BEAST477
I think those heads will be what limits your hp unless they've had some hand work done to them.
Yep, not enough head.
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Old 01-09-2012, 03:55 PM
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Originally Posted by oldandtired
Originally Posted by BEAST477
I think those heads will be what limits your hp unless they've had some hand work done to them.
Yep, not enough head.
:shock: :shock: :shock: :shock: :shock: :shock: :shock: :shock:

Racers rule of thumba.."Heads equal HORSEPOWER!!!"
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