rizZO-6

My father-in-law is in the process of a restoration on his 69. He recently swapped the auto to a 4 speed. Now we're trying to figure out which front exhaust hanger to use. The exhaust is for an auto and was replaced before he got the car so he is reusing it. But the hanger was missing so he needs to get a new one.

My question is to the people that have done the swap on an early C3, which hangar did you use? It looks like either hanger will need to be modified.

Also, does anyone know the measurement of space in between where the pipes would clamp on either an auto or manual hanger?

Thanks!

Alan 71

Hi r,
Which hanger to use is determined by which transmission and mount is being used.
For a 4-speed transmission and 4-speed mount the 4-speed hanger should be used.
By time the exhaust pipes get back to the point the hanger and clamps are they're both (4-speed/auto) are the same.
Regards,
Alan

Here's the 4-speed transmission, transmission mount and the exhaust hanger… with out the pipes in place.

540 vette

I am doing the same on my 72. This is the hanger I used, there is also a 2 inch one.

http://www.parts123.com/corvettecent...50g&ukey=12771

Nothing will need to be modified if you are using the stock parts and have all the parts you need. Do you have the "tongue" that bolts onto the crossmember to support the 4 speed? You can see it in Alans picture.

Easy Mike

Do your father-in-law a favor and purchase the 69 AIM for him as an early Father's Day gift.

rizZO-6

Thanks Alan. I saw that pic in another thread. Very good pic! He has a Muncie 4 speed and the correct 4 speed mount (like yours in your pic). I read in another thread that the exhaust pipes on a 4 speed go straight through the holes in the cross member. But on an automatic the passenger side exhaust goes through at an angle downward. And that's what my father-in-law's does. If you see the two different hangers you can tell that the one for auto is angled a little on one side, which would work good for his pipes. But it bolts to the back of the tranny so that is not good. I think we are going to go with the same hanger you have for a 4 speed and twist it a little on the one side to accommodate the angled pipe.

rizZO-6

540, have you already completed the swap? If so, you were able to use that hanger without any modification? Has your exhaust been changed or are you still using the exhaust that came with the automatic?

He has the same "tongue" as the one in Alans pic.

rizZO-6

Hey Easy, I was supposed to buy him an AIM for Xmas but instead got him a driveshaft that he needed.

I guess I could get him an AIM now for an early father's day gift. He's hoping to have the car on the road by then!

Alan 71

Hi r,
Thanks for the additional pipe information. I learned something!
When I first looked at the 2 pipes I didn't notice the 'angle'… but now that I look again I see what you mean.
I hope I didn't mislead you too far!
Regards,
Alan

Here are a few pics of the 4-speed front pipes in place. I don't know if they'll be a help to you or not.

rizZO-6

No problem Alan. Thanks for the additional pics.

By the way, your car is beautiful underneath... so clean one could eat off it!


[QUOTE=Alan 71;1593899776]Hi r,
Thanks for the additional pipe information. I learned something!
When I first looked at the 2 pipes I didn't notice the 'angle'… but now that I look again I see what you mean.
I hope I didn't mislead you too far!
Regards,
Alan

Here are a few pics of the 4-speed front pipes in place. I don't know if they'll be a help to you or not.

DUB

Good luck with tweaking your exhaust to make it work. Not meaning to put any bad MOJO in this for you...but I feel you will be fighting with angles that will not work...especially when you go and try to use the correct muffler clamp and seal of the pipe and also attach it to the new exhaust pipe hanger bracket like what Alan has shown.

I am well aware of the bracket that is attached to the rear tail shaft housing of the TH400. It is very unique.

The only reason I am adding my thoughts on this is because I have dealt with this issue and many other issues when getting the exhaust to be secured at the back of the transmission area and not be all butchered up.

DUB

rizZO-6

DUB, I wasn't talking about tweaking the exhaust but tweaking the exhaust hanger. That's why I started this thread to see what people have done to the hanger that have completed the auto to manual swap. I have to imagine that anyone that has swapped trannys has run into this issue. Maybe people are just eliminating the hanger after they have done the swap.

DUB

Yes...the hanger can be cut and re-welded if a person wanted to do that....and take the time to make sure what modifications they are doing are actually going to provide the strength needed to do its job.

I have seen some really poor ideas (that failed) that some people have used to try to hold the exhaust. I know it needs something there...so doing without a good mount location I feel would not be wise.

DUB

ronarndt

"I have seen some really poor ideas (that failed) that some people have used to try to hold the exhaust" Dub- my PO bubba took your run of the mill Autozone rubber strap hangers and MIG welded the metal part of the hanger to whatever part of the pipe was closest to a hole in the frame/floor/whatever to fasten the rubber strap. I guess it's better than using coat hanger wire. I've seen that too.

540 vette

I haven't done the exhaust yet but I have a 4 speed exhaust.

DUB

I have seen what you described ...which simply put....those hangers do not work.

I roll my eyes and begin to cuss because I know I will have to start from scratch.

What often times seems to be funny is that when I am asked to deal with exhaust pipe issues...some customers feel it is a 5 minute job and rig it up so it works.....BUT....little do they know...it often times does not work like that.

This is when I try at all costs to get them to take it to a muffler shop and let them do whatever they want. Because if I can not do it RIGHT...I rather not waste my time.

DUB

rizZO-6

Just a quick update. My father-in-law ended up buying the exhaust hanger for a manual. He says he has it bolted in and it will not require any bending.

How that is, I don't know because I am not there to see it in person. Based off what he told me and the picture he sent me, his exhaust passes through the tranny cross member at an angle. But if he says it works, I'm all for it. One less thing I have to worry about

Alan 71

Hi r,
"But if he says it works, I'm all for it."
This generally a good outcome!!!!
Moving forward!
Regards,
Alan