Just finished install on my 4r70w - 1972 302. I heated and bent my headman headers to fit nicely but with a few months of winter left I was curious if people have used the Doug thorley headers and how well they fit around the bellhousing area on this transmission. For that matter the same thing would likely apply to the aod guys out there too. I'll post a picture of the crossmember just to show it. It's a modified version of frank aod.
Well with the lack of discussion, maybe I should ask the aod people. How have the Doug thorley headers worked for you?
I can't see the problem as much different than a C4. Bellhousing is probably going to need trim, size is mostly dictated by circumference of block. In either case it's going to require custom bent pipe to route from header outlet to under chassis. This is my Comet prior to cutting finger from C4 bell, needless to say I'm less than impressed.
Wow that is closer than I expected. Seeing this picture alone is enough for me to just keep with the headers I'm currently using. Thanks
Did you modify the header extension to clear the pit arm? I didn't have an issue w/ C4 and Hedmann shortie headers; only had/have issue contacting pit arm on left turns?
The muffler shop cut the extension and routed away from pitman arm. I believe there is some minor interference at full lock, but not enough to decrease turning radius. I suppose the fact headers fit with column shift is a plus. I now have complete floor shift setup including column, trans lever, etc. Gonna try to get on that this spring.
I'm still in shock about how tight they are considering the 88300 managed to fit well past the everything even with the larger bellhousing. Besides the fact I did go to floor shift. For the $720 they are asking I'd expect a little more. Although I'm sure the quality is superior in itself.
Quality of construction is no doubt a cut above anything else, actually a bit over built. Extra heavy tubing, plus the three bolt outlet somewhat limits adjusting angle of pipe. Assuming one has access to a lathe, could be opened up 1/8" or so. I bought mine in '13 for $399(market seemed flooded at time), would not been in consideration at $700+.