waterbum

I need to shorten my CMI tailpipes and was wondering how to "flare" the inner pipe to the outer pipe after it is cut. I can't find anyone in the area with a big enough flaring tool. My welder says he can run a bead around the opening (leaving the top open for water exit).

Any suggestions?

Thanks,
Doug

US1 Fountain

iTrader: (1)

Thats kinda how Corsa modified my Gil risers. Just cut to length, then tacked a SS rod to the inner tube at bottom creating a somewhat dam. Can't weld to both inner and outer pipes do to the different temps making for different expansion rates.

I tried muffler shops at first since they have hyd expanders, but none were big enough.

Mr Gadgets

You dont want to weld them together, because of the different temps and expansion of each pipe like US1 said.
If you cut the outer pipe a bit shorter, you can weld a metal strap to the inner pipe. Make the inner about 1/8" longer, take 1/2" SS strap, wrap it around the OD of the inner pipe and cut three slots about 1/4" wide. Actually you end up with three pieces. Make the strap as wide as the gap and push it between the two pipes. That worked for me on a set of pipes I built some time back..

Good luck

Dick

Mbam

Yuo can do it in a hydraulic press, you just need something tapered that you can press in. You will be amazed how the pipe will expand. Never tried it with the inner & outer together though, usually done before the pipes are assembled.

RedDog382

Doug,

Did you consider sending them them back to C.M.I.? I had some modifications done to my tailpipes in the past by them. I think you want to talk to Randy(?).

Chris

waterbum

Thanks for all of the suggestions. I thought about sending them to CMI, but it seemed like a pretty simple procedure if it could be done locally. I have to slide mufflers over the ends anyway, so I was not too concerned how they looked. I just want to make sure there is enough restriction to force water to the top of the pipes for cooling.

I'll try a couple of truck repair shops that work on large pipes (exhaust).

US1 Fountain

iTrader: (1)

I was charged $100 and 2 week turn around time for the modifications. Was under impression they would be cut and reexpanded, not the simple cut and weld a rod in. You can do this yourself in lesss than 1/2 hr.

US1 Fountain

iTrader: (1)

I think the amount of restriction will be noticable on a WP gauge. Should be able to get real close by trying to match the amount of opening needed to the amount presently.

blue thunder

waterbum, I am curious what the length of your tailpipe is going to be. I just shortened two sets of eickert tails to about 6.5" and was not going to do any damming because they are so short. The water is introduced on the top and I believe, as did Innovation Marine, that there will be sufficient splash at that length pipe to keep the top cool.

BT

mcollinstn

No big deal. Just get some stainless tubing appx 5/8" OD. Run it thru a roller bender until you make a loop the same size as the OD of the outer pipe.

Then use a 36 grit beltsander to grind one complete side of the loop until the tubing has a "C" crosssection instead of an "O" crossection.

Now leave the open part of the loop at the top and weld both the inside and outer pipes to the loop. The open section of the "C" will allow flex for thermal expansion and it will present a clean and finished end.