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Discussion Starter #1
I recently purchased an 86 GT and noticed it doesn't make the power that my 87 did. I've heard that a head change in 87 made alot more power, and i've also heard rumors of the 86 upper intake being more restrictive than the 87's also. Upon inquiring about getting some stock 87 heads, i was told that there might be valve clearence problems, but only if i get it up above 7k rpm...
Is there any truth to any of this?
Can i put 87 heads on? and will i make any more power with an 87 upper also?
Does anybody know the full story? What else might be different?
Thanks
 

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True Dat...
the 86 makes 25 less hp and a few less pd ft of tq. It is faster than your 87 0-60..but after that loses steam real quick due to its shrouded High Swirl heads. You should be able to swap the E6's for the E7TE's with no issues whatsoever. However to be on the safe side always check vlave clearance. As far as the 7k thing...why would you ever spin the stock 5.0 up that high? It doesnt make any power up there..so I know of no one that has had problems with this idea.

The upper intake TB opening is 2mm smaller...doesn't sound like much, but can make a difference. You could replace it with a belly button stock upper from the 87-93 cars...but why? You can find Cobra/GT-40 aftermarket manifolds for almost nothing now days...bolt on a 65mm TB and make some VERY noticiable power.


Hope this helps!
 

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Discussion Starter #3
Well I can get some e7's and an 88 gt upper for $25 which is nice and in my kind of price range. I don't ever intentionally put my car up to 7k, but I was told that things like a missed shift in an 86 with e7's might be hazardous, but only maybe... How can i go about checking valve clearances so that I can know for sure one way or the other... I don't really like having grey areas.
Thanks for your help!
 

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I just did the same thig on my brothers 86. I ported and pollished the E7's and left the stock valves in. Added 1.7 crane RR and a GT-40 intake. 1988 TB and a cold air kit. He says its like night and day !!! I would say this is a great modification.
 

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Discussion Starter #5
well if it will clear 1.72 RR with un-notched 86 pistons i'm sure i have no worries, thanks again for ya'lls help.
 

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Mighty Mouse said:
True Dat...
the 86 makes 25 less hp and
Nope. More like 5-10 hp. But, you are correct tha 86's eat other stangs in the 0-60.

seijirou: What do you mean by "down on power". In street driving, the 86's are better. They have more low end (below 2000). You may have a clogged h-pipe or worn cyls.
 

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with the 87 head install..shouldn't that make his 86 have a crap load more low end power?? raising the compression.. wouldn't that give his car a lot more low end torque?? im curious..cause im in the middle of doing the same thing...but.. i have a set of heads off my 89 that i was gonna use...is there a difference between the 87 and 89 head...does it have anything to do with the mass air and map??? let me know befor i got and install these 89 heads :p thanks


Ben
 
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