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Hedman Header hitting Idler Arm

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Old Jul 14, 2015 | 09:42 PM
  #1  
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Default Hedman Header hitting Idler Arm

I have 77 L-82 w/o AC and the Hedman Header is 68308, my problem is that i noticed that the pipe off of cylinder 4 is right against the boot of the Idler Arm. It has made a mark on the header, but my concern is that with the excess heat it will melt the boot. It looks as though someone has put a small shim in behind the Idler arm to try to move it slightly, to help it get away but not enough. I believe shimming it more will pull things out of center. Does anyone have any ideas or fixes they could recommend? I'm thinking my only option is beating the header in enough to give clearance. ( there goes that warranty ) LOL
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Old Jul 15, 2015 | 12:19 AM
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There's no excuse for how bad those things fit. I ran a set one time and couldn't believe it. There's tons of room to have designed it properly. And they hang much lower than necessary also.

Most end up with a dent. Shimming is going to move it closer to the tube isn't it? You could put some DEI header wrap around the section.

Make sure to grease the idler frequently because it will bake it all out quickly.

Best bet is to take pics and send it to them and see if they will take them back.


JIM
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Old Jul 15, 2015 | 01:47 PM
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Originally Posted by 427Hotrod
And they hang much lower than necessary also.

Most end up with a dent. Shimming is going to move it closer to the tube isn't it? You could put some DEI header wrap around the section.


JIM
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Old Jul 15, 2015 | 03:39 PM
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before I coated mine I dry fitted them and dented as necessary. The idler arm was one spot I have to dent in.
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Old Jul 15, 2015 | 08:53 PM
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The SHIM is at the top of the Idler Arm, which I think is pushing it away from the header a little i think. As far as the wrap goes, there's no room now for the pipe and the boot - I dont think i could ever get a piece of tape between them, but thinking of maybe putting some on after the denting process. And yes i'm keeping an eye in the grease. Thanks


Originally Posted by 427Hotrod
There's no excuse for how bad those things fit. I ran a set one time and couldn't believe it. There's tons of room to have designed it properly. And they hang much lower than necessary also.

Most end up with a dent. Shimming is going to move it closer to the tube isn't it? You could put some DEI header wrap around the section.

Make sure to grease the idler frequently because it will bake it all out quickly.

Best bet is to take pics and send it to them and see if they will take them back.


JIM
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Old Jul 15, 2015 | 08:57 PM
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qwank - were you just able to dent the pipe at the Arm or was there more modifying necessary down the length?




Originally Posted by qwank
before I coated mine I dry fitted them and dented as necessary. The idler arm was one spot I have to dent in.
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Old Jul 15, 2015 | 11:48 PM
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I purchased a set of these barely used for my 69, only issue was a dent on the passenger side tubes but I was very happy with my repair job until I bolted them on.

Immediately discovered the interference issue with the idler and realized the error of my way. Took it off, re did the modification and all has been great since. You would think after 45 years Headmann would have fixed this issue.
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Old Jul 21, 2015 | 07:30 PM
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I was told I could wrap a come-along around the headers and put a little tension on them, then run the engine to heat the pipes and let them cool, put more tension on them and heat again and cool, to bend them toward the block. There is all kinds of space in there. Does that sound like it would work? Or do you think I will need more heat?





Originally Posted by TX-Techman
I purchased a set of these barely used for my 69, only issue was a dent on the passenger side tubes but I was very happy with my repair job until I bolted them on.

Immediately discovered the interference issue with the idler and realized the error of my way. Took it off, re did the modification and all has been great since. You would think after 45 years Headmann would have fixed this issue.
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Old Jul 21, 2015 | 11:08 PM
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You could put a tie down strap around them so you didn't bend or scratch them and use a come along to pull them over. Probably do it cold just fine. Heat might help...but then you have to re-think the strap thing...

JIM
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Old Jul 22, 2015 | 08:44 AM
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Check trans mount make sure motor is not skewed over to the passenger side also make sure motor mounts are good ..
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Old Jul 22, 2015 | 11:37 AM
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Late to reply here, but I had the same problems as you. I used a body shim to angle the idler arm away from the headers, and a little hammering to create a smooth flatspot. To this day it's worked fine for me.
I will not buy headmans again....
Here is a link to my thread
https://www.corvetteforum.com/forums...an-elites.html
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Old Jul 25, 2015 | 05:21 PM
  #12  
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I want to thank all who helped guide me to a peaceful resolve. I was able to shim the Idler arm a bit and pulled the headers by using a pc of asbestos tape rope and a tie strap ( though I only separated them by 1/8"-3/16" ) I feel more comfortable with just knowing its not resting on the header. On the plus side, I didnt do any damage to the arm, boot, or header. It took a few times of heating and cooling also. Thanks again. I only hope that i will be able to help someone, as youz have helped me.
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Old Jul 26, 2015 | 09:50 AM
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Did you check all mounts using a pry bar and some leverage to ensure they all where good ? Or did you just decide it needed to be bent ? I have 2 inch tubes and mine do not hit , they have 1/4 inch clearence.. BUT at first they did hit and that is when I found the trans mount was the issue.

Usually a header hitting is a CAR issue not the header maker screwing up .. So what you may have done is solve a header issue while leaving the root cause to fester ...

And PS I had and sold the exact same header set you are using and I corrected issue as I stated above and went to 2 inch tubes when i swapped in a SBC 427
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Old Jul 26, 2015 | 11:26 AM
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Thanks for the input diehrd, i had only looked at the mounts briefly - never yanked/pried on them per say. Do you know is there somewhere giving a measurement for distance from the mounts ( like something could have been bent do to say an accident or just plain bottoming out? Otherwise I could be creating another issue down the road..




Originally Posted by diehrd
Did you check all mounts using a pry bar and some leverage to ensure they all where good ? Or did you just decide it needed to be bent ? I have 2 inch tubes and mine do not hit , they have 1/4 inch clearence.. BUT at first they did hit and that is when I found the trans mount was the issue.

Usually a header hitting is a CAR issue not the header maker screwing up .. So what you may have done is solve a header issue while leaving the root cause to fester ...

And PS I had and sold the exact same header set you are using and I corrected issue as I stated above and went to 2 inch tubes when i swapped in a SBC 427
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Old Jul 26, 2015 | 12:39 PM
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I have Hedman headers on a BB, with plenty of clearance at idler. I did have to dent the #3 pipe to clear the steering box. That is only because I have after market heads with raised exh ports.
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