[Devilman]

Has anyone used these heads on an 86 block that originally came with 86SE heads? My concern is the the missing valve relief on the pistons. I have been researching it and I have found people who say it would be ok and other who say the piston to valve distance is too close. Anyone know off hand?

[BlessedHellride]

I would dare say it's ok, but I'm not 100% sure. Just have to be mindful of PTV clearance when selecting a cam

[1slo5.0]

Originally Posted by Devilman Has anyone used these heads on an 86 block that originally came with 86SE heads? My concern is the the missing valve relief on the pistons. I have been researching it and I have found people who say it would be ok and other who say the piston to valve distance is too close. Anyone know off hand?

Probably not. Everything about the 86 engine is different from the 87-93 engines. The pistons, heads, intake and throttle body are all different. You would be better off buying a complete 87-93 engine.

[93mustank]

I've done it twice..... one car cleared the other didn't. Always measure.........

[chad05gt]

helped a friend w/ the swap years ego, worked, but wasnt worth much...

[Devilman]

yeah I gotta measure it.......I am putting a 91 GT cam in it. It just sucks to have to bolt the junk E6SE heads back on it when I have a 91 set of E7TE heads for it. I do know I don't want to do it again. What really sucks is this is one of those autoZone rebiuld motors that is slapped together with mismatched parts. D1 rods, E7 block (roller), E6SE heads and pistons (thunderbird or something). Of course it has the oddball 5.0 rings (155hp) all put together and stuffed in a 91GT. hopefully I can come across enough folks who have done it and not bent stuff up.......

[93mustank]

Originally Posted by chad05gt helped a friend w/ the swap years ego, worked, but wasnt worth much...

Hmmm....

I gained 7 tenths from the complete swap... 13.9 to 13.3 with no other changes.

[superbean]

87+ production short block are pretty dang cheap...

Or take that 86 block and buy a new set of pistons with more valve relief and not worry about it.

[Devilman]

Originally Posted by superbean 87+ production short block are pretty dang cheap... Or take that 86 block and buy a new set of pistons with more valve relief and not worry about it.

It is an E7TE block but someone bolted the other E6 stuff in it. I'm pretty sure I'll end up putting pistons in it....

[oldslo88]

I don't know that I would risk putting it all together, only to find out... you know? What was plan B incase they don't work? Maybe try that first?

[Devilman]

I'm clay testing it today, but most likely will bolt the E6 heads back to it. I mean, it will run fine it just won't have the top end range it should. In an otherwise stock car it shouldn't be a big deal. we'll see and I will let ya'll know witht the PTV clay test...........

[93mustank]

Originally Posted by Devilman I'm clay testing it today, but most likely will bolt the E6 heads back to it. I mean, it will run fine it just won't have the top end range it should. In an otherwise stock car it shouldn't be a big deal. we'll see and I will let ya'll know witht the PTV clay test...........

You converted to lifters to solid correct?

[chad05gt]

Originally Posted by 93mustank Hmmm.... I gained 7 tenths from the complete swap... 13.9 to 13.3 with no other changes.

Really, it was worth .15, and we even smoothed out and filled the emissions 'nipple'!


This car had 600cfm carb, 3.73's, headers, 1.7RR's, udp's 'bolt ons'... so stock cam and bottom end w/ 5 speed.


I dont know if you had stock bottom end/cam?


(reguardless, this threads takin' me back! GOOD stuff! )

[1fst5.0]

i did with a pair of 93 heads, no problem, its been about 4 years now. they did make a difference

[Devilman]

Originally Posted by 93mustank You converted to lifters to solid correct?

No I haven't, a little more detail and tell if ya see a problem....... the block was an E7TE with a rollor cam in it. It was a SO spec built engine with a like firing order I have found. It had E6SE heads bolted on it. Again it was an Autozone rebuild special with flat top pistons like an 86HO or any other SO 302 thru like 89 or so. Upon finding this abortion built motor I installed a 91 GT camshaft to get it to a Mustang firing order. I am installing it in a fair condition stock 91 Mustang. With all this said, the valves(E7TE) were real close to the pistons (1/8 or so) with the 91 camshaft. I think I should go with the E6SE heads to keep it safe. Whadda you think?

[Devilman]

Originally Posted by 1fst5.0 i did with a pair of 93 heads, no problem, its been about 4 years now. they did make a difference

Did it have flat top pistons? I would like to put the E7TE heads on it...........

[1slo5.0]

Originally Posted by Devilman No I haven't, a little more detail and tell if ya see a problem....... the block was an E7TE with a rollor cam in it. It was a SO spec built engine with a like firing order I have found. It had E6SE heads bolted on it. Again it was an Autozone rebuild special with flat top pistons like an 86HO or any other SO 302 thru like 89 or so. Upon finding this abortion built motor I installed a 91 GT camshaft to get it to a Mustang firing order. I am installing it in a fair condition stock 91 Mustang. With all this said, the valves(E7TE) were real close to the pistons (1/8 or so) with the 91 camshaft. I think I should go with the E6SE heads to keep it safe. Whadda you think?

What 93Mustank is saying is you have to use a solid lifter when checking piston to valve clearance because you will bottom out the hydraulic lifter which will show more clearance than what you really have.

[Devilman]

Originally Posted by 1slo5.0 What 93Mustank is saying is you have to use a solid lifter when checking piston to valve clearance because you will bottom out the hydraulic lifter which will show more clearance than what you really have.

oh. No I don't have any handy. with this little note, Then I probably have even less clearance then I believe I have now.... as much as I hate it, I am gonna bolt the 86 heads back on it to be safe. I appreciate the insight.......Brightside, I have learned alot here when it come to mismatching parts, what works with what and such. Downside, time spent though has cost a lot more than if I had of just sucked it up and bought a Mustang engine........