What is the performance difference ?
 

what is the performance difference between equal length shorties and regular shorties as far as performance goes?

just trying to get some more hp from this 86 gt.

Equal lengths outflow un equal lengths by a small margin.

When I say a small margin, I mean small;)

If you want max. HP gain then I would go with a setr of long tube headers.
If you're already set on buying shorties, then I would recommend the unequal length headers because getting to the header bolts will be much easier.(or is it the plugs?)
I forget now but getting to one of those will be a bitch to get to with the equal length.

i think getting to the plugs on the passenger side with equal shorties will be a pain in the @ss

I think you are entirely correct :)

I had bought equal length shorties and ran them for a year, had nothing but problems with plug wires burning and installation was a B*tch. Not worth the hassle, I got rid of them and went with MAC ceramic coated unequals.. I didn't see a single power difference or mileage, and they look great either way and plugs fit nice and wires don't burn. Definetly screw the equals.. Not worth the hassle.

I like my equals and while they did change the exhaust tone a tad bit, I cannot say that the performance changed any. I occasionally toast a wire before I tied them together and the passenger side plugs require some acrobatics to get in but nothing spectacular. How often does one change plugs anyway? Not often enough for that extra 2 minutes for the 2 trouble plugs on one side to really matter _that_ much. A tiny performance gain is still a gain.