Slow or what ??????????

Phantom5oh · 10-15-2001, 09:13 AM

you might have a bit left in your combo, but the 351 heads are killing you... the combustion chambers are not shaped or sized right for use on a 302, let alone a 289... they bolt right up, but they aren't the best heads for that combo... sure they flow better and can fill the chambers with more volume than stock, but its the chamber size and shape as well as the ports that aren't made for use on a smaller bore motor... it can be done, but its just not as efficient as a head made for a 289/302 i would also suspect that unless they are ported/gasket matched then there is turbulance around the intake ports becuase of size differences... i bet you would get more from a pair of stock heads... maybe even toss a home port job on them, and she will be faster... mine is an '83 too and its a bit heavier than a newer one (maybe cause it convertible) but i know its heavier than my buddies 89 GT... anyways i have 2 pairs of stock head if you want one... good luck, i hope this helps

Phantom

------------------
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Loose Cannon Racing
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10-15-2001, 09:13 AM	#5
Phantom5oh Registered Member Join Date: Mar 2000 Location: Boston, MA Posts: 334	you might have a bit left in your combo, but the 351 heads are killing you... the combustion chambers are not shaped or sized right for use on a 302, let alone a 289... they bolt right up, but they aren't the best heads for that combo... sure they flow better and can fill the chambers with more volume than stock, but its the chamber size and shape as well as the ports that aren't made for use on a smaller bore motor... it can be done, but its just not as efficient as a head made for a 289/302 i would also suspect that unless they are ported/gasket matched then there is turbulance around the intake ports becuase of size differences... i bet you would get more from a pair of stock heads... maybe even toss a home port job on them, and she will be faster... mine is an '83 too and its a bit heavier than a newer one (maybe cause it convertible) but i know its heavier than my buddies 89 GT... anyways i have 2 pairs of stock head if you want one... good luck, i hope this helps Phantom ------------------ Project Bird Turd Loose Cannon Racing Scarzi Machine Works