First Run ....Not So Good
04-23-2008 | 06:21 PM
#62
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From: Grand Rapids MI
OFFTHEFRONT
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Anyway the blocks are decked,bored and now have .30 Weisco forged pistons tha t are 9.6 to 1. Had the whole assembly balanced and put together. I got two sets of heads from Andy here on the board they are 990's that have been cleaned and milled for straightness. I bought two new AirGap intakes, a Custom cam that is a 228/238 .544.544 and a pair of HP 500 carbs that are going on top. I am hoping for 450-460 RELIABLE HP. we shall see in couple weeks because this is costing a CHIT LOAD OF DOUGH...
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Anyway the blocks are decked,bored and now have .30 Weisco forged pistons tha t are 9.6 to 1. Had the whole assembly balanced and put together. I got two sets of heads from Andy here on the board they are 990's that have been cleaned and milled for straightness. I bought two new AirGap intakes, a Custom cam that is a 228/238 .544.544 and a pair of HP 500 carbs that are going on top. I am hoping for 450-460 RELIABLE HP. we shall see in couple weeks because this is costing a CHIT LOAD OF DOUGH...
04-23-2008 | 07:41 PM
#63
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From: Olmsted Falls,Ohio Marblehead,Oh
I would try 750 carbs to start, I know they are good to 500 hp, the HP500 carbs are 800's and may be a tad too big, if nothing else you have a little better engine then a 420HP, .30 over, cam only a tad less kift on exhaust, otherwise they are the same as 420's should have been that easily..
04-24-2008 | 07:29 AM
#65
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From: Grand Rapids MI
I would try 750 carbs to start, I know they are good to 500 hp, the HP500 carbs are 800's and may be a tad too big, if nothing else you have a little better engine then a 420HP, .30 over, cam only a tad less kift on exhaust, otherwise they are the same as 420's should have been that easily..
04-26-2008 | 09:05 AM
#66
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From: Grand Rapids MI
it is what it is. I am not real happy but it is prolly 100 more HP na side than i had before. Here is the dyno sheet Don't forget to click on iit will get bigger so it is easier to read
04-28-2008 | 07:51 PM
#69
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From: Bay City, Mi
I can relate to your ordeal Car Biz. Two years ago I bought a 1990 272 with a pair of 454's. Boat ran fine for about 5-6 hours of run time. Opened the hatch one day while idling and noticed a water leak between the intake and the block. Checked the dipstick and it was loaded with water. Pulled the motor, cracked block. I went the easier way and threw in a 420 crate motor. Last winter I matched the other motor with a complete rebuild. Last summer was pretty much trouble free. 1st year sucked.
