Use/don't use stainless flex pipe-Modding Pypes down pipes

[79 USA 1]

Have you contacted Pypes about this problem? Looking at this picture you posted,

The flanged pipe is not welded square into the 90 degree bend. If you were to tighten that up to seal to the cast donut on the manifold it would put the pipe into the oil filter or the floor pan.
If Pypes will not do anything about it, It may be worth finding a local muffler shop with a tube bender and see if they could put a slight correction bend in the tube after the 90.

 

[pagrunt]

I'm using the '64-'77 down pipes with a pair of '76 manifolds. Basicly running a custom fit. I didn't want to put in press bends in the pipes unless I really had to. I would like to keep everything with mandrel bends but that may be alittle anal. At times I wonder why I wouldn't use the Hedmans instead of selling them.

 

[79 USA 1]

I used the same manifolds on my 406 when it first went into my 79 Monte Carlo. At the time I ended up using a set of head pipes for a 74 Monte Carlo and had the rest of the system bent from the transmission crossmember back.
Might be worth a call or email to Pypes to see if you ended up with a down pipe that went down the assembly line on a Monday morning.
I understand not wanting compression bends in a mandrel bent system.

 

[pagrunt]

I'll have to give them a call tomorrow then. The down pipe looks like the bend is a 90.

 

[fleming442]

Slice the pipe, and weld a wedge in.

 

[565bbchevy]

Basically running a custom fit. I didn't want to put in press bends in the pipes unless I really had to. I would like to keep everything with mandrel bends but that may be a little anal..

It seems to me that your only option is to hold off finishing this portion of the build until you can either buy or borrow a welder since all of the other options you are considering are "band aid" fixes to get around doing it the right way which is cutting and welding and being a "little anal" about it means you shouldn't settle on anything that isn't done right. IMO

 

[pagrunt]

I talked to Pypes today about the drivers side down pipe. The guy I talked to said this issue is starting to be a problem with them as I'm not the only one calling about it. It was bent based on the sample pipe that was made years back that wasn't 100% on but was never changed/corrected to match the angle of the earlier style manifolds. He couldn't even understand that. He sugested to bend it in the area best to correct the fit. I'm going to swap out the MagnaFlow 91006 cats fot the 53006 cats (5-1/2" vs. 4-3/8" wide) to get some more clearence.

It seems to me that your only option is to hold off finishing this portion of the build until you can either buy or borrow a welder since all of the other options you are considering are "band aid" fixes to get around doing it the right way which is cutting and welding and being a "little anal" about it means you shouldn't settle on anything that isn't done right. IMO

I'm not rushing at this point. As this whole project is literally a one man project (only possible help is in-laws who would rather scrap everything before spinning a wrench, no gear head nieghbors) I'm trying to work on everything in a way that allows me to complete eash phase that budget freindly & looks clean. My welding skills are not even close to the work some on the other members kids can do so I don't want to do a hack job. If I can do a clean job with cutting down & using the proper bends, I'll go that way. I like the advice I have got & will try to apply it. With the welder I have, I'm going to barter with the wife to slide some time from house work to garage work to update the wiring so I can weld (or my imitation of welding.)

 

[pagrunt]

After a two month break from the exhaust, decided to take another look at it. First, compaired my newer style manifolds to a set of junk older style. The drivers side dump angle is a few degrees more to the rear so it will be abit easier to adjust by either find the right spot to put a slight bend of just use a ball socket set. Now the passenger side has had some other adjustment issues come to light. The newer & older styles do have a slightly different angle too, but the dump is alittle further out from the block. I could adjust the down pipe & not worry about it but the cat will not fit in the hump of the crossmember (pipe sits just off the outer side.) Now I'll just have to figure out how I want to position the cat to work the passenger side.

 

[pagrunt]

Well I found a surprise from when the UPS guy bounce/ tossed/ delivered the exhaust kit, the folking right tail pipe is bent!!! 😡😡😡😡😡😡 I was thinking cause everything was loose & able to move about it would be in the right position when everything was clamped tight. So I position & snug just enough so I can still adjust the tails, position the mufflers then...the muffler is angle up, the tail hits the bumper. 😵 I'm looking to see if I bumped something, bent a hanger. Got out the tape, started to measure. Yep, it's bent. That was the pipe that was packed with mud. Called Summit to see what they could do since I already had them comp me. I have a complete kit on the way now since they couldn't just get the tail pipe. 👍 Had to give back the $47 comp but was need to for the UPS claim. So if UPS doesn't bother me within ten day I'll have an extra Pypes kit for parts. So I'm on another break from the exhaust until I have to pack the first kit to give to back to UPS (I hope they don't want it.)