I would also be interested in the results Joe, if youre going to dyno with shorties and full length.
I had a Luv with a 383 that I ran some old junky 1 5/8" shorty (block hugger) headers which I port
matched. They were like the old ram horn manifolds as they all came together about 6" below the
center two cylinders. They had 2 1/2" 3-bolt collectors, after which I ran 3" pipes with an X-pipe, then
necked down to 2 1/2" Dynomax turbo mufflers. The 383 made 483hp/495tq with some nice 1 3/4"
dyno headers. But I used the junky 1 5/8" block huggers that came in the Luv truck when I got it.
It ran decent with the shorties, 11.30s @ 122. Then I bought the Hooker Super Comp 1 3/4" full
length headers, stuck them in (with the same exhaust) and went back to... unfortunately something
was wrong with my Luv, it just ran like crap, and I couldnt figure out what was wrong with it,
it just felt like it was down on power everywhere. It was NOT the full length headers, because
it had run great with then on the street before. The only thing I found was a possible vacuum leak,
and to this day I dont know what was wrong with it, and more importantly how much the full length headers
would have been worth at the track. I will say this, it felt like it had a bunch more (30-40?) tq from
around 3000-5000 above that it was about the same power wise. But the thing to consider is the shorties
were 1 5/8" dia. and 6-9" long, and the full length were 1 3/4" (which is what the engine really needed I believe)
with 32" long primaries. So the shrties may have been on the small side diameter wise which may have helped
with tq a bit, but the primary length was way too short for power below 6500rpm, which should have been around
32" for that low a rpm band.
Now I'm in a similar dilemma, I just picked up a nice street Vega which looks really tight and shortie headers
would be so much easier then the 1 3/4" Hooker super comps which they make for it. So I need to figure out if
its worth the hassle to do the full length Hookers or just get some shorties for it and be done with it...
the same 383 is going in the Vega.
Thanks for any input.
girly rollers on pumpgas:
420 - 641hp BretBauerCam, 1.39, 9.79 @ 137.5
383 - 490hp 224/224, 1.56, 10.77 @ 124.6
502 - 626hp 252/263, 049s 1.44, 10.08 @ 132.7
62 Nova cruiser
383/200-4R/12-bolt w 373s
224/224 HR cam
1.57 10.97 @ 121.2