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5.0 1986 roller heads
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Posted by: jcmtang

I have a set of 1986 roller heads i want to put them on a 79 302 flat tappet eng does anyone know if they will fit on a older 302 block 1979, i know the rocker arms are the same as a flat tappet eng, that is the parts man said the rockers were the same parts number ,so i would think the older push rods should work,anybody done this ,thanks jim.

Posted by: VETTKLR

Does that 79 motor have notched pistons for the valves?

I remember the 86 302's had flat top pistons and the heads were the least to be desired.

Seems like something was up with the PV Clearance, flow numbers, or both...geez, it's been years since I've seen anything regarding those 86 heads.

At any rate, the heads will bolt directly to the block and the rockers will work. Pushrod length may vary, depending on the head. 86 Mustang GT's were roller cams, so the pushrods would be shorter than an 86 F-150 head because it would have still been a flat tappet engine.

Posted by: jcmtang

yes my pistons have 4 valve notches in them , i have the heads on the eng now and i am having low compression readings 80lbs is the best ive got so far i cc the heads an they were at 56cc give or take a little, am stump? should have at lease 120 lbs. o these heads are s code thunderbird i think.

Posted by: VETTKLR

Ah hell, are the rings new on the pistons? Were the heads cleaned up and treated a valve job before the install?

Posted by: jcmtang

yea all new but, i have it running an i still have 80lbs of compression all around lol ? i didnt think it would start no compression .sounds ok but i dont have it in the vechile yet i always start one on the floor before i put it in .maybe i need to go to a bigger cc head an take some pressure off the rings its just a old standard bore with some ware lol,i have a set of e7te heads and a set off a 1987 351w havnt looked at those yet.

Posted by: VETTKLR

With the rings being all new, they would probably require some seat time before you actually got 100+ psi to show.

Get some breakin time on it and see what she does then.

Posted by: jcmtang

yea am going to run her some ,i have a set of e7te heads with a little bigger cc chamber may have to go to them an take some pressure off the rings lol.

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