Compression

Old 10-25-2008, 02:29 PM
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hammertime
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Default Compression

Hey guys, thinking about bumping my compression up this winter, not 100% trying to figure out if the hp/et gain is worth changing up my combo.
Now it has 12.5 going to 14.5-15, 582 BBC made 970hp

What hp and on track et you think i'll gain by 2 points ?
thanks in advance !
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Old 10-25-2008, 03:53 PM
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jmarksdragster
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May help a little with consistency as well as HP. I'm going between 15 and 15.5 on my 460.
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Old 10-25-2008, 04:26 PM
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zipper06
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Alcohol love's compression, you can't get too much. Look at it this way top alcohol cars are running 12 to 1 and spinning the blowers at 40% OD pushing 40lbs boost. In the mid 80's i was running a 1471 blown alcohol 540" B/blk with 13 to 1 and spinnig the blower at 40%. I've got 11 to 1 in my s/blk with a 1471 and spinning it 1 to 1. I have 13.7 on the 377" and 14.5 on my 434"

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Old 10-25-2008, 06:02 PM
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pickup in hp and et for sure.
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Old 10-25-2008, 07:12 PM
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i know you have heard enough about PAR racing engines lately...but here we go again.... all his raw motor engines is nothing less then 15 to 1..
My 15 to 1 565ci with smaller heads (valves) than yours is making 30 hp more than your 582ci

you put your 582ci 15 to 1 and i personally think you will put that bad boy close to the 1100 hp mark if the rest of your combo is right for the job. :wink:

I will say 80 to 100 hp gain and 2 to 3 tenths quicker...your 4.70's and 136 mph range now..right ?

IMO
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Old 10-25-2008, 07:35 PM
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hammertime
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Originally Posted by itsabird
pickup in hp and et for sure.
How much is the main questions I guess, we talking 2-3 hundreths ?

Its very consistent as is, just thought if I was leaving a good tenth on the table ?

I've did this move before 10:1 to 15.5:1 on a alky motor, seen very little gain which I thought was odd.
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Old 10-25-2008, 07:38 PM
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Originally Posted by bjuice
i know you have heard enough about PAR racing engines lately...but here we go again.... all his raw motor engines is nothing less then 15 to 1..
My 15 to 1 565ci with smaller heads (valves) than yours is making 30 hp more than your 582ci

you put your 582ci 15 to 1 and i personally think you will put that bad boy close to the 1100 hp mark if the rest of your combo is right for the job. :wink:

I will say 80 to 100 hp gain and 2 to 3 tenths quicker...your 4.70's and 136 mph range now..right ?

IMO

Most high end builders are 15.5-16:1 making 1080-1100. I'd go out on a limb and say mine goes 1040-50 maybe higher on any dyno but Nyes. That dyno has to be bar none the most honest dyno I've seen.

80-100hp gain that'd be worth the jump for sure. Right now 4.7'[email protected] instead of 136
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Old 10-25-2008, 10:10 PM
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michael1
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I wanted 12.5 and my engine builder told me to put at least 15-1 he said it would be a major difference but I'm building a 632 18* motor with two dominators. Ask Pat at Nyes you know he won't stear you wrong,he is very honest.
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Old 10-26-2008, 07:30 AM
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bjuice
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Hey compression is HP anyway you spread it..weather its achieved thru a turbo,blower,NOS or just built into the motor Naturally aspirated. there are no 11-12 to 1 engines setting any records out here...unless its static compression with a 30/35lb huffer sitting on top...lol
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Old 10-26-2008, 07:54 AM
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BJUICE you gona run that new one on alcohol or gas?
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