Franks73

I installed Hooker stainless steel headers and side pipes on my 73 small block. The left side is touching the frame, and the right side has maybe 1/8" of clearance. I read the thread on this issue, seems like a common problem. I can't imagine contact with the frame is a good thing. I have polyurethane motor mounts. Wondering if a thinner mount would give some clearance, but I haven't found that option. I don't want to go with solid mounts. I also have not found a good way to dimple a stainless steel header. It seems like my final recourse, is to remove the headers, and dimple them with a ballpeen hammer. As always, thanks for any thoughts on the subject.

stingr69

I would replace the mounts with stock rubber replacements to see if it helps.

Tampa Jerry

A few things come to mind. I put poly motor and transmission mounts on my 70 SS Chevelle. As a result, the stock fan hit the shroud. I switched back to stock rubber mounts and all is well. On my 66, the side pipe on the passenger side touched the idler arm. I marked the pipe with a Sharpie and removed it. I took it to a local muffler shop that put a dent in the pipe using their pipe bender. Depending upon the location of the interference, but this may be an option. Both solutions are a PITA. Good luck. Jerry

Rescue Rogers

you dont want to smack the pipe when you massage it. Put a socket or a round piece of metal on it then smack that object. Force will tansfer to the header and give you the dent you need where you need it with less chance of damage

resdoggie

I had the exact same issue with my Hooker ss side pipe headers.

I used two hammers, one being a ball peen which I placed on the header tube and whacked it a few times for the desired massage. I did have to install/remove several times to get it right but I didn't want to screw around with motor mounts. I like my poly!

Edit: It's a fact that dented headers add horsepower. Engine Masters proved it and they are the foremost authority on engine performance.

Rescue Rogers

Solid mounts wont change the feel of the car or transfer any vibrations to the frame, if thats why you dont like them. I have them in my car with a big block and its actually better

resdoggie

The OP doesn't need to spend any money to fix his issue which is quite common. The dented tube(s) are usually unseen or hard to see unless you really look.

Franks73

I will try to find out the difference in dimensions. If there is enough difference, would give it a try. Thanks.

Franks73

I have never tried solid mounts. I confess, I just assumed there would be vibration. Also thought that was why the factory installed them. I respect your opinion, thanks! I wonder what the consensus is with other C3 Vette folks?

Franks73

I agree, the dents will be down by the frame, hard to see. Of course money is always a consideration, but also what will be the least pain in the butt factors in.

Sayfoo

The easiest thing to do (if your mounts are in good shape) is to not remove the headers, and then stick a pry bar down into where the pipe touches. Wedge the bar back and forth and keep pressing the bar into the opening till you get the required clearance. You probably don't need much--1/16"?? Then you can rev up your engine to see how much it moves and adjust the clearance as needed.

Franks73

That is a very interesting idea! Kept thinking stainless would be a tough metal. Sounds like that would be worth a shot!

wwiiavfan

The motor will move considerably more under torque load than just revving it.

cv67

I Imagine the stainless would be pretty tough to massage. Unless its really wedged hard on the frame Id leave it be

I used the largest socket I could get my hands on, put a towel over the jet coated finish then with bfh wacked it at a slight angle, came out perfect. Was mild steel not stainless though. Hate the way a ball peen hammer dent looks.