j heads..more perf. questions

I didnt want to jump in and change 66dartmans thread on "j-head to eddie swap" but I think I have learned a bit about what I have from just reading that thread. Now, maybe someone can shed a bit-o-lite my direction on my J's that I have dumped toooooo much money in.

long story condensed.
'74 360 .60 over 9:1
Had originally had the j heads reworked and installed the 2.02 valve upgrade and had a performance job done on them....this was quite a few years ago.
ran this with the mopar stick .284/.484 and a sure grip set 3:91 and 727 with a 3000 stall.

My car was a real pig off the line, but once she got rollin hold on! she would take high RPM's like crazy and love d it up there.

Problems. They reared their ugly head shortly after the build.....I had taken the car back to the engine builder to see why no low end. (keep in mind this is about 5-6 years after the work was done) so no goin back on them. They said the car had no compression. What ? took the car back hoime with my tail between, and strated tearing the bastard apart. Removed the heads to find the pistons had a nice wobble side to side in them.....was at .40 over at the time. YUCK. Pulled engine and sent to a known good shop and they cleaned it up. They checked the heads and asked why it worked at all? Apparently they were pretty botched up. (have a list of what was wrong..not important here) they said they could fix them.....I beleive this shop. Got everything back together on the beast and fired it up. Seemed pretty good and ran better than before, but still a pig off the line. Can only get a bark from the rear tires WOT. So, through some research found that my cam como might have been a bit off. Purchased the xe268 Comp. cam and rechecked......gained....quite a bit....very noticeable difference on my take offs, but still only barking the tires.....pulls hard and fast though.
I am lost where to look now. I guess getting the tires to turn isnt a priority, especially cause it isnt going to be a racer, but it should and thats whats bugging me. So here is the current build. Does someone see a problem here?
360 at roughly 9:1 compression
j heads with perf job, large valves (maybe too much work for engine?)
eddy RPM intake
holley street avenger 780 ( I know what your all goin to say, but it likes this carb the best)
double roller/stock type rockers
MP ignition chrome box. accell distributor and super stock coil, 8mm wires
stock exhaust manifolds (this is a killer)
2 1/2 " tubes flowmaster 40s
trans = 727 loadflight / torqueflight (came from a truck) reworked with 3000 stall convertor.
8 3/4 rear with 3:91 sure grip grinders.
thats the main scoop. Shouldnt she burn the skins......can include tire size if any questions....
any one want to take this on? feel free to pm me too.....
sorry so long.

-RPM