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Working to get my car on the road and putting a set of American Racing Headers on my small block L-46. Finishing up replacement of the positive battery cable (worst job ever) and bolted in the hears to check initial fitment.....not great...
Headers appear way to high and to the outside to properly bolt up to the mid-pipes, which will definitely hit the floor pans. I doubt they will move that much when doing the full install and bolting exhaust up first and the header flanges to the block last.
Anyone have any suggestions or experience with these headers?
I had the same problem with their headers and sent them back for refund. They were nice about it. I will never understand why exhaust manufacturers cannot make a set of headers and pipes that fit on a production car. I have complained to several, and the standard answer is that "Corvettes in the 70's had a large tolerance in manufacturing....so one car can be substantially different than others". I agree with that,....except, its bullshit. Maybe a 1/4 inch tolerance. The very expensive headers I have bought are INCHES from being right.
I had the same problem with their headers and sent them back for refund. They were nice about it. I will never understand why exhaust manufacturers cannot make a set of headers and pipes that fit on a production car. I have complained to several, and the standard answer is that "Corvettes in the 70's had a large tolerance in manufacturing....so one car can be substantially different than others". I agree with that,....except, its bullshit. Maybe a 1/4 inch tolerance. The very expensive headers I have bought are INCHES from being right.
Thanks for letting me know! Yeah they are like 1” off in each direction and have tons of room to otherwise fit correctly so I have no idea what’s up.
Last edited by monza_man; Oct 8, 2020 at 12:15 PM.
I actually talked in person with Nick, the owner of ARH. He prototyped a set of C3 LS swap headers on my car. They had my car for 3 weeks to get it right. He also said the tolerance on cars is big. Not only body to frame but who knows who’s engine mounts are used and there are a lot of other variables that go into this equation. I have installed dozens of headers from various manufactures over the years and they are all over the place. That is not an excuse and I am not saying any header place is better than the next. I have found that most good muffler shops will be able to bend and adjust for a proper fit. Never found a “box” system that fits worth a crap.
I actually talked in person with Nick, the owner of ARH. He prototyped a set of C3 LS swap headers on my car. They had my car for 3 weeks to get it right. He also said the tolerance on cars is big. Not only body to frame but who knows who’s engine mounts are used and there are a lot of other variables that go into this equation. I have installed dozens of headers from various manufactures over the years and they are all over the place. That is not an excuse and I am not saying any header place is better than the next. I have found that most good muffler shops will be able to bend and adjust for a proper fit. Never found a “box” system that fits worth a crap.
I have to agree, but it sure makes it tough to buy a $2000 system, and have to have custom pipes bent. The quality of welding and pipe bending on ARH was outstanding, and I liked the choices they made on bends which provided great clearance on steering box and idler arm, but I did not understand why one header ended two inches aft of the other side????? If there was a reason, I don't know what it is. It seems they should end at the same place in space front to back. But,.....I used StainlessWorks since that was the pipe and muffler system I had wit the 350, and when I build I installed the 406, I bought new 1-3/4 inch headers to replace the 1-5/8 inch headers. I had to get one custom pipe made by StainlessWorks for the left side. The right side fit.
I also have a set of these that I purchased about 2 years ago and haven't installed them. I haven't fit-tested them and now --------- I'm worried.
You should be, as it is way past time to return them. I returned mine. BUT.....again, these are very well made, including excellent bends, and excellent welds. I just don't know why they do not fit a stock car. But to be fair, I had same problem with StainlessWork and Magnaflow. My car has not been in an accident, is straight and I know it because I made the measurements during the body off, and there was no sign of damage anywhere in the chassis or body. SO....all that is left is this weak idea of "tolerances". Really, I don't expect exhaust to just fit perfectly, I can accept a little "massaging"......but these exhaust were WAY PAST massaging. I don't build cars this way. It simply should not be this difficult to fabricate an exhaust system to fit a production car.
Last edited by Shovels and Vettes; Oct 7, 2020 at 11:01 PM.
That borderlines on Bubba solution. It should not be necessary.
Yes, sir, it's actually well across the bubba line - but - I'm sure you are aware these were 1100 bucks a couple of years ago - I can only imagine what you paid recently. Another pipe bend would easily be tolerable but it looks wayyyyy close to me. That would take some pretty fancy bending. The flexible pipe may just as well still contact the car causing rattles rubs and possibly burns in the contact area. This is some pretty disheartening news about the AR headers. I am, however, very glad that monza_man started this thread. I have some 'stuff' to try and remedy before this mess catches up to me...Thanks for the comments and info.
The ARH headers fit great on my car, significantly better than the Hedmans they replaced:
For what it’s worth, my car is a 78, with a Dart SHP 400, AFR 195 Eliminator heads (slightly higher exhaust ports than factory), energy suspension engine and transmission polyurethane mounts, TKO 600 mounted to a G-Force crossmember.
The tightest area - and it’s very tight - is the idler arm.
My fitment issue with ARH headers and transition pipe was not clearance to the floorpan area. Mine had about the same clearance to the floorpan as Shark Racer's pictures show. My problem with that the transition pipe on the left side, provided by ARH, was WAY OFF from going through the hole in the crossmember. It was not even close. I had great clearance at the idler arm. In fact the way better than the StainlessWorks headers I now have. BUT.... ARH headers also ran much closer to the mini starter I have. So, understandably, with large tube headers, there is only so much space. I could have, and maybe should have, worked with someone to bend a custom pipe to transition the left header to the crossmember hole, as ultimately, that is what I had to do with the StainlessWorks headers, but I assumed, again wrong, that StainlessWorks headers would fit.
I will add that I too have AFR 195 heads, which have raised exhaust ports, but remember, they are only raised 0.100 inch, which is less than 1/8 inch. I hardly think that changes much. Shark Racer has TKO600 transmission, so that may have an effect on fitment if the transmission relocates the aft mount in space. His pictures appear to show the headers are pointing down and not parallel to the floor, as the transition pipe IS parallel to the floor??
'IF' i had the car laid up for a while (which i probably won't even in winter when i can get it out dry)..unless catostrophic failure...
i would make my own headers..because of these issues..
mine is stock L82 with every accessory so if i didnt have all that and custom maybe not..
i would document on here..
i would center the collector in the 2 holes and custom bend everything to avoid every are possible.. kinda like jamming in hideaway mufflers between spare and fender antenna etc..
i would buy something like this.. used and / or share on this forum or bite the bullet on a kit new and share..
premade flange and collector..and practice practice practice..tack with mig i have..
send out for TIG welding to complete and or the real reason.. i want a TIG welder to learn..
if happy .. send out for ceramic..
i would price it as a welding class experience and adventure..
My plan as of now, since I’m in these for $1K+, is to cut the collector off with a pie cut on the inside at the narrowest point and then re-weld them back up.
I think I should be able to adjust the angle quite a bit inward to avoid the corner of the floor pan and then bolt them up to the ARH midpipes. Wish me luck...more updates and pics forthcoming!
My fitment issue with ARH headers and transition pipe was not clearance to the floorpan area. Mine had about the same clearance to the floorpan as Shark Racer's pictures show. My problem with that the transition pipe on the left side, provided by ARH, was WAY OFF from going through the hole in the crossmember. It was not even close. I had great clearance at the idler arm. In fact the way better than the StainlessWorks headers I now have. BUT.... ARH headers also ran much closer to the mini starter I have. So, understandably, with large tube headers, there is only so much space. I could have, and maybe should have, worked with someone to bend a custom pipe to transition the left header to the crossmember hole, as ultimately, that is what I had to do with the StainlessWorks headers, but I assumed, again wrong, that StainlessWorks headers would fit.
I will add that I too have AFR 195 heads, which have raised exhaust ports, but remember, they are only raised 0.100 inch, which is less than 1/8 inch. I hardly think that changes much. Shark Racer has TKO600 transmission, so that may have an effect on fitment if the transmission relocates the aft mount in space. His pictures appear to show the headers are pointing down and not parallel to the floor, as the transition pipe IS parallel to the floor??
I’m running the G-Force crossmember, and before that a BTO 700R4 crossmember with the TKO. I can’t compare to the TH350’s placement, as I never worked on that transmission when it was in the car - but I wouldn’t imagine that the crossmember is laterally changed much. Pinion angle vs tailshaft angle has to be maintained, up-down and left-right to avoid vibration problems.
Another benefit of the crossmember is elimination of the exhaust holes, replaced with slightly raised pieces of box steel, with a much wider “margin of error” than the factory crossmember.
Personally, I’m not bothered by headers requiring fabrication to meet the midpipes, it’s a fact of life, particularly compared to stock exhaust where they have a lot more room to fix the run before it reaches under the car, since they clearly didn’t prioritize primary tube flow over packaging. I also wouldn’t expect the aftermarket manufacturers to work together on a single common collector location.
I would expect the headers to avoid anything the car should have - idler arms, floorpan, steering box, etc.
Help!! ARH exhaust install on ‘69.
