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Old 12-22-2002, 01:14 PM
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Post engine math

i picked up a winter projest for free, a 75 dodge pick up.
i want to build up the 318 a bit and i need a bit of help.
i am shooting for a daily driver/parts hauler.
mild performance.
automagic trans, shift kit, stock converter.
this is my first engine project, and i would like to get 1hp. per cube or just under. about 300 hp. i think that is reasonable.
i guess i don't know where to start.
ihaven't taken the engine apart yet.
anyway, i don't know the bore and stroke of a 318, or how to figure compression ratios.
i'll be using the stock heads, and a 0.030" over bore if all goes right.
any help or direction would be a great help.

i had every thing all planed out, then i sat down to type this out, and i lost it. shucks!

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Old 12-22-2002, 02:20 PM
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Hey Josh.
First thing to do is tear the engine apart and see what you have. It could have already been bored over and rebuilt once already.
For compression, find out what heads you have and the cc on em, then when you check on pistons just get the ones that will give ya 9-1 up to 10-1 for pump gas.
As far as cam goes, figure out the rpm range your wanting to run and talk to the cam company, they can hook ya up.
If you dont know bore, stroke, ect... from info on here. Try www.moparchat.com They can tell you everything on there. Its strictly mopar. Hope I helped. HG
I was built with the body of a God! To bad it was buddah.


Hemmies rat journal below.

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Old 12-22-2002, 02:39 PM
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300 to 320 horsepower in your 318 should be quite easy.
If you want to keep it simple, use your stock heads, have a top notch, three angle valve job laid on them, pocket port the bowl of the heads, and do a mild gasket match on the intake and exhaust, if they have the air injection tubes in them, you can block them off. You can opt for the earlier, 360 style heads if you wish, they will flow better, with a bigger valve, and improved ports, but they wouldn't be necessary with the power level you want.
I would stick with a stock set of flat-top type cast pistons, just do what's necessary to make it dimensionally sound.
Keep cam timing on the conservative side, Mopar performance has some nice grinds, but the old 340 hydraulic cam comes to mind. Crane makes a blueprint copy of that particular cam, and will make good all-around power.
If you want to save some money, hunt around for an old 340 cast iron, Thermo-Quad intake, and matching carb. The T-Quad will make the best power, if it's rebuilt right. Follow up with small tube headers and dual exhaust, tune it, and it will shock you with it's power and mileage.
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Old 12-22-2002, 07:22 PM
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thanks a bunch guys!!!!!
merry christmas
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