Hi, ive been going through my 76 and have replaced ALOT of stuff on it. Yesterday i replaced the exhaust with mid america duals, and magnaflow mufflers. This is a true dual setup and i need pics of your pipes where they pass by the spare tire carrier. I have mine installed but the passenger side pipe looks to be hanging a little low, and it is close to the crossmember by the tranny. Other than this The kit is very nice and the drivers side went on with no issues. thanks

 

This is to be expected. C3's have pretty wide tolerances in terms of their original construction, so a little close here and a little low there are normal. The best thing to do is bolt it together as best as you can...and if it's not acceptable, take it to a custom exhaust shop and let them bend the pipes to exactly what you need.

 

I've wondered how true dual fit under a 76, since it orginally had a cat converter and the pipes ran under the passenger side only. Does the tranny crossmenber have the two holes in it like the earlier C3's?, or do both pipes go to one side where the cat converter used to be?

Just curious.

 

heres how they run on my 81, both down the passenger side, only had a cutout on the passenger side.

 

sorry the pic was so big first time I tried that

 

My 76 with a 4 speed has duals that are ran down both sides through cutouts in the crossmember on each side of the transmission. If I ever have them replaced I want to have the drivers side with some way to separate it just behind the crossmember so I can work on the gear shift if needed. I don't see any way I could ever replace the 4 speed shifter with a Hurst shifter if I wanted to. You can't get to it for the exhaust pipe.

 

Here are mine (78) before I had to get "legal" in Calif....


two holes in cross member from factory...but not stock exhaust...notice heat shield on only one cat..

 

Two holes in the tranny crossmember right up thru '79. No problem installing true duals. And there's also a kit for '80-up that runs the pipes side-by-side.

 

Thanks for all your help, I ended up just twisting the rear section up about 1/2 inch and that made all the difference in the world. Its still close to the cross member but does not hit so im not worried about it. Isnt it funny how we come about installing some things? this all started with me installing new motor mounts and a tranny mount, and it has gone out of control from there

 

for what it's worth, i added real duals to my 78 pace car (L48). if i had it to do over again, i would have been smart enough to go with the L88 size pipes (2 1/2) instead of 2". since the system is the same when it leaves the exhaust manifold and is enlarged to the 2 1/2 size right below the exhaust manifold flange, it would have been easy. my bad!! never thought of it however at the time. that said, i found that the crossmember hanger kit from corvette central made the whole system a lot more stable by holding the pipes in perfect position as they each went throught the cross member (installing true duals requires that you remove the trans pipe hanger and the rear "y" pipe hanger as neither will provide the proper alignment. before i clamped the intermediate pipe to the head pipe on each side, i used a pry bar (a very long heavy duty screw driver will work just as well) inside the end of the intermediate pipe to turn the pipe into a position i was happy with in terms of clearance under the differential heat shield. then i clamed it together and tightened the hangers for each pipe at the crossmember.

for what it's worth, i chose to go with ansi (or monza) type exhaust tips and resonators ONLY. no mufflers what so ever (emissions control is not an issue on older cars in south florida, hence the cat elimination and the no muffler application). it reproduces the side pipe sound without the actual side pipes. you can accomplish the same affect (if that suites you) and maintain a more tradition apperance from the rear if you choose, by using one of the baffled systems that are available from just about every major parts house. they will cost you a bit more than using stock pipes and the resonator tips, but they will look more traditional and produce the same sidepipe exhaust sound.

 

This was essentially the question I was going to ask. I am picking up my new '72 350 4 speed this weekend and want to get rid of its junky aftermarket sidepipes right away. So I can put the 2.5" LT-1 system on it with no issues around the exhaust manifolds? If so, great. Can someone confirm that for me? Thanks.

 

I assume your 72 is going to be the same as my 76. I installed the 2.5" system and had no problems anywhere except for around the rear crossmember, but i got that straightend out

 

strack350, What part no. did you get from mid america for your 76? stainless or aluminized?

vic

 

My '75 has two holes in the crossmember even though it's a cat car, then branches into two again at the rear of the car.

 

I'll confirm this. A very common upgrade. It's what I was going to do until I found a really good deal on some long tube headers. Just make sure you buy the 2.5" for small blocks, it will have the 2" opening for the exhaust manifolds. Big Block versions have a 2.5" opening. However, there used to be 2.5" small block manifolds, I think they were from the old fuelly 327 or 283's or something like that. Of course for that price you might as well get headers...

What are you doing with the side exhaust kit?
trw

 

I used the aluminized kit part# 603-790, and ordered some 2.5" magnaflow mufflers. I never drive my car in the rain so it should last forever

 

Aluminized are fine for all weather and last forever. The only difference with them and the stainless besides price is that aluminized will grey up a bit and the welds will start to look a little cruddy over time but should not have any rust out problems.
vic