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HammerDown
08-24-2003, 04:17 PM
The old 468 at 10:1 compression and 049 heads worked over, is spinning my Aggressor Full>(A) at 51-5250 rpm. 5500 would make me content, for a while.
Without going to a smaller Impeller, or adding NOS, or a Blower...I'm guessing the only way to raise my R's would be with more Compression, bore, or stroke ?(aint to crazy about strokers).
PS. carb and timming are dialed in where they should be for the current RPM.
[ August 24, 2003, 05:22 PM: Message edited by: HammerDown ]
Fired Up
08-24-2003, 06:02 PM
More info needed....what carb or carbs, intake, ignition system, fuel pump set up are you using? What cam (solid, hydraulic, roller) are you spinning?
Snorider
08-24-2003, 06:17 PM
You are already just about at your compression limit to where pump gas doesnt work well, so more compression is kinda out of the question. Granted, 10.25:1 is probably still safe for 91octane, but you wont gain much.
See if you can get some more portwork done to your heads, or get a set of aluminum ones... With aluminum heads you can bump your compression higher because aluminum dissipates heat better than cast iron. Most of your horsepower is made in the cylinder heads - the more they flow, the faster you go (within reason)
kojac
08-26-2003, 06:57 AM
Hammerdown,
My brother has a 468 with 049 heads, 10.5.1 compression. Pulls a "B"to 5700 5900 depending on air. We tried an "A"impellar and pulled it to5500 5600 depending on air. Get with me and I will go over the specs with you and see if there is something simple (hah, On a jetboat!.NOT!)we can change or switch to improve your rpm's.
dale...
HammerDown
08-26-2003, 08:41 AM
kojac:
Hammerdown,
My brother has a 468 with 049 heads, 10.5.1 compression. Pulls a "B"to 5700 5900 depending on air. We tried an "A"impellar and pulled it to5500 5600 depending on air. Get with me and I will go over the specs with you and see if there is something simple (hah, On a jetboat!.NOT!)we can change or switch to improve your rpm's.
dale... Thanks Dale...I will PM you what I have in the motor...but Im keeping my Aggressor full (A)..lol
HammerDown
08-26-2003, 12:52 PM
Kojac...check your PM's>>>>