Guys, I have to thank the experts on the Corvette forum and the search button. While installing my new headers, they would not fit on the passenger side. After doing some reading, I found that some people had a lip on the frame that required grinding. My car had almost an inch of material past the spot welds next to the bellhousing. After some grinding to remove the excess material and a bit of black paint, the headers fit perfectly with plenty of clearance. Fortunately, the spot welds were right up against the frame, so I removed material up to the spot welds, leaving a very small lip. Hope this helps someone else doing an install, as this seems to happen occasionally.

 

Thanks for the info. What brand headers did you go with. I just got LG's last week. Was unable to install them this weekend so I will have to do it next weekend.

 

I had to make similar moodifications when I put 1 7/8" headers on my NONz06 C6. I dont think 1 3/4" headers require these moodifictions.

 

This issue is an easy fix and is brand related. Grind it back (the frame)and paint. NO issue. One of the big three.
This brand has wider spread. Lets say brand A. Brand A also has the
cats futher back behind the x in the x-pipe.
Brand B has a narrow spread where the tubes run closer to the block.
plus brand B has the cats ahead of the of the x in the x-pipe.
but doesn't have the issue of the tubes hitting the frame.
Both are great quaility. I have owned both and installed and reinstalled
both, they both fit well!

 

Just did 1 3/4 AR's and had the same issue . Well the shop did. They grinded the blk frame and painted it for me. I was actually getting some wicked hissing noise prior to it so not sure if the contact was making that happen or the o2 sensor. So that was corrected after the grind. Only problem I am having now is some rattling but seems to be coming from my NPP's maybe something loosened up when they did the headers. When the shop asked me if it was ok to trim the frame I was told my face turned ghot white but it turned out being nothing. Sounds much worse than it is.

 

I believe this happens by tightening down the drivers side first but I could be wrong.
That is how I installed mine and they weren't touching the frame but close enough that I went ahead and cut the extra metal off and then sanded down and primed/painted the small area.

Love my AR Headers!

 

50 years from now some restorer will be cussing the "imbecile" that cut this other wise perfect frame just to install a set of poor fitting headers!

Tom

 

Gunter, they are AR Headers. I have bought them in the past and found them to be excellent quality and fit with great customer service. They also have very good resale value when you remove them before you sell your vehicle. AR Headers do everything right, they fit perfect, don't leak, come apart, rust or rattle and most importantly, they are made in America. Much different than headers from the 70's and 80's. I am a loyal customer. Rock'n, I don't agree that this issue is brand related. I have read posts about the same problem from others of the big 3. TCW, if someone is restoring this car in 50 years, they will be smoothing every edge and finishing it to be a show car. The extra metal removed from the edge of the frame does not affect the structural integrity in any way. This to me is clearly an issue with manufacturing standards. The extra metal in question fits within the standards and does not interfere with the OE exhaust, so why should GM change it? Now I have called those before me names when they would take a torch and cut a 4x6 inch hole in the frame of a 69 Chevelle to make a set of headers fit, but that is not the case here. Like others that have posted before me, I too love my AR Headers. Thanks Nick for making a great product!

 

Typical on AR 1 7/8"

 

I had the same problem with my LG 1 7/8 headers, but I didnt gring the lip. I took a big pair of vise grips and bent the lip down. That way it can always be bent back if the headers come off.

 

Does anyone have a picture of where this is rubbing... I only have it at part throttle...

 

Does this issue come up with AR 1 3/4 headers too?

 

This is precisely what I did with my A/R headers. Actually I think I bent mine up with a BFH. I got one of the first sets off the die. I spoke to Nick about it, and he told me that it's hit or miss to this day. Some cars need the massage, some don't!

 

You'll see it. It's helpful if you can put the car on a drive on lift or ramps, so the weight is still on the tires and the frame isn't tweaked like it can get on jack stands.

 

This has been an issue with any headers on a C6. Some need the metal lip "massaged" a bit and some don't. This is not a brand or primary tubing size specific issue. It has more to do with manufacturing clearances in a tight area. If you do a search, you will find this has come up before and virtually every brand name has been mentioned. It is not a big deal, just something you need to know going in so you are not caught off guard.

 

Seems to be C6 related only, doesn't really matter which of the big three. The 1 3/4 Kooks on my C5 fit perfectly - I haven't heard of any fit issues on the C5 on that matter.