How much to cut out for fenderwell headers?

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pettybludart

pettybludart

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I,ve purchased some fenderwell headers from Hedman part #(75110-66),these were custom order so there...on there way.Does anybody have pics or measurements for how much of the inner fender I have to cut-out?I,ve seen Blownfishes and 66340sedan,s(Keith)jobs and they look very clean.Any help with some measurements,pics would help greatly.Thanks

P.S These are going on my 1966 Dart with a 408 and P&P Eddy RPM,s.
 
I hope this helps. Mark

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Try to contact the header manufacturer or the retailer and see if either one has a template. They must have access to one somewhere.
 
Give me a few days and I'll try and get some measurements and I'll dig around to see if I have any photos of the engine compartment before I assembled the car, and no! they didn't come with any templates. I just cut away a little at a time until I got the fit I wanted.

Just remember, with the Headmans, you will need to notch the shock mount or at least heat them and dent them.

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Thanks guys,I had noticed Keith(66340sedan)had kept a cutout piece and reattached after installing.Looks done properly.YooHoo K e i t h...:read2:
 
What size tubes did you order? If you went with 1 3/4 you'll have to trim a bit more around the shock tower. you also may want to consider a brace for your shock towers.
 
dart4forte said:
What size tubes did you order? If you went with 1 3/4 you'll have to trim a bit more around the shock tower. you also may want to consider a brace for your shock towers.
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The headers are 1 7/8 tubes.Yes,braces will be in order for strength.
 
Blownfish. The radius cut corners on your car really make all the difference world. Really gives it a look of quality and craftsmanship.
 
1968FormulaS340 said:
Blownfish. The radius cut corners on your car really make all the difference world. Really gives it a look of quality and craftsmanship.
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Thank you!

I tried to take the extra steps where ever I could, I also filled the original hood hinge area since I was running a lift off hood and filled any unnecessary holes in the engine compartment that I could.


Here are a few photos without the engine in the way. The right shock tower needs to have a pretty good size notch for the #4 header tube and the left side needs a small notch for the #3

My cut line along the rear, runs where the fenderwell and the support on the firewall meet, then I just followed the shock tower along the front, you can pretty much see where they run along the top which I just cut out as I mocked it up. You may want to see how it fits in your car before you cut it because I have my engine raised about 1/2" above stock.

You will need to get header collectors also, the Headmans are race headers and don't come with any. I bought a set of the 2 bolt Flowmaster collectors for mine, they look like oversized catalytic converter collectors. They have more ground clearance than your standard collector since they don't have the flange like the typical header collector, and they don't leak. You will also need to re-locate the little tabs they use to hold both halves together or they will tear up your front tires when they touch.

The additional support wouldn't hurt but there is no reason for additional shock tower supports unless your running coil over shocks, it doesn't support the cars weight or anything and the notches are above the point where the shocks mount

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pettybludart said:
The headers are 1 7/8 tubes.Yes,braces will be in order for strength.
Click to expand...

You will have to do some surgery around the shock towers. As far as braces it's been my experience that cutting around the shock towers creates stress in the unibody. Buddy of mine has stress cracks in the area of his shock towers. Of course his car wheel stands quite a bit and coming down that hard does put stress on that area of the body.
 
Great pics Blownfish,thanks for taking the time to post.These will be saved for when it,s time for surgery.(next week)
 
pettybludart said:
Thanks guys,I had noticed Keith(66340sedan)had kept a cutout piece and reattached after installing.Looks done properly.YooHoo K e i t h...:read2:
Click to expand...

I actually made those covers out of sheet metal, thanks for the nice comments, I will try to post some pics later tonite for ya!!!
 
 
Mine are Mopar Performance which means they are Headman's that JR headers put on slip on collector's. Here is one picture of how much I cut up on top of the inner fender.

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Blownfish said:
Thank you!

I tried to take the extra steps where ever I could, I also filled the original hood hinge area since I was running a lift off hood and filled any unnecessary holes in the engine compartment that I could.


Here are a few photos without the engine in the way. The right shock tower needs to have a pretty good size notch for the #4 header tube and the left side needs a small notch for the #3

My cut line along the rear, runs where the fenderwell and the support on the firewall meet, then I just followed the shock tower along the front, you can pretty much see where they run along the top which I just cut out as I mocked it up. You may want to see how it fits in your car before you cut it because I have my engine raised about 1/2" above stock.

You will need to get header collectors also, the Headmans are race headers and don't come with any. I bought a set of the 2 bolt Flowmaster collectors for mine, they look like oversized catalytic converter collectors. They have more ground clearance than your standard collector since they don't have the flange like the typical header collector, and they don't leak. You will also need to re-locate the little tabs they use to hold both halves together or they will tear up your front tires when they touch.

The additional support wouldn't hurt but there is no reason for additional shock tower supports unless your running coil over shocks, it doesn't support the cars weight or anything and the notches are above the point where the shocks mount

Photo0061-1.jpg

Photo0062-1.jpg

P1010671.jpg

P1010672.jpg

P1010705.jpg

P1010706.jpg
Click to expand...

How did you get that chrome heat shield to clear your headers....I have one of those and couldn't not get it to clear for nothing.
 
Very cool threa! It's a well known fact that our A bodies have very limited header clearance. Thats why Im tossing the inners!!
 
moparlee said:
How did you get that chrome heat shield to clear your headers....I have one of those and couldn't not get it to clear for nothing.
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It is close and I had too finesse a dent over the one tube but it fits.

This brings up another tip with these headers, you have to have the MC off or moved out of the way to install the left header. I would also recommend using dot 5 brake fluid, it will help if you have any heat issues and it won't hurt the paint if you were to spill any.
 
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