OJMiles

LTs are required (recommended?) on Ps because ford rotated the spark plug to a different angle, supposedly makes better power, but interferes with the short tubes ... at least thats what I remember reading

mrbigshot

correct, they are goofy as it was required because they are a fast burn low emission head.

you dont need $500 dollar headers. some shortys will clear (with a few love taps) and nearly all longtubes will clear. also plug wire dont need to changed you just need to go to the parts store and get 4 90 degree terminals, and boots. if you can swap heads im sure you can crimp 4 plug ends. YOU CAN USE THE SAME OLD MAC LONGTUBES THAT EVERYONE SELLS! headers are bad because they dont have any air injection smog stuff, thats why there bad. im sure you could make some explorer or mountineer manafolds work with some creative pipe work.

if your not going to change the stock manafolds out dont bother getting ported heads, they will choke it out.

VigCS

Hmm...these GT40p's are very tempting. Only thing that makes me weep about the LTs is the fact that the kill low end torque, which I want (the torque that is). $579 for a pair of reman'd GT40p's from a good vendor? Sign me up!

mrbigshot

lol i can get them threw my work for $329 a set remaned, and i handle the cores (as im the only engine knowlageable person there) so i could turn in crap e7's. i can also get 69-73 351w's for the same price. no i wont get them for anyone else. the low end loss is negligble is its a loss in the midrange as you can se in the test below. it was done on a bone stock 5.0 using mac shortys vs mac longtubes. same diameter pipe. as you can the the long tubes made more peak and average hp and made more torque up to 3200 rpm, after 3200 rpm the short tubes made more torque up to 4000 rpm, over that the long tubes once again made more torque.

why by shortys? the only area the are better is torque production from 3000-4000 rpm. before 3000 and after 4000 the long tubes made more torque and they never got beat in terms of horsepower.