Author Topic: advice anyone??  (Read 2706 times)

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Offline mstrdinan

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advice anyone??
« on: April 18, 2009, 10:22:39 PM »
we have a 300 inch chev   holley 750 double pumper         12 to 1 compression
victor jr intake ...    36 degree advance       
running 112 octane gasoline
getting 484 hp@8300  at sea level

 jets are .078 in front...088 in rear

 any ideas what to change in jet department for the salt
or anything else for that matter
 engine man say he should get another 50-60 hp ...has tried a few things but all changes resulted in less hp
                                                                                                     thanks to all

Offline fredvance

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Re: advice anyone??
« Reply #1 on: April 18, 2009, 11:15:00 PM »
IMHO I think you dont have enough compression for 112 octane gas, high octane gas burns slower. It would probably make more HP on pump super premium,
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Offline Dynoroom

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Re: advice anyone??
« Reply #2 on: April 18, 2009, 11:34:25 PM »
Working with what you have IMO I'd leave the jetting alone. I always run lean best power on the dyno here at sea level. This makes the tuneup for five miles at altitude close when running a carb. Then I'd bump the timing because of the low compression and altitude depending on the type of cylinder heads you've got. It's hard to get compression with a small engine but it pays for your efforts at the salt. What class are you running? There is no silver bullet when running normally aspirated so what ever you've got is what you've got.

Good Luck & have fun.
Michael LeFevers
Kugel and LeFevers Pontiac Firebird

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