38KV

I'm working on my new tail pipes and was thinking of welding the tubes together in the rear end and leave a slot open for the water.

Question is, how wide should I make the gap? 4" inner and 4.5" outer tube.

waterbum

I had to do the same thing when I purchased some used tailpipes that were too long. I had them welded at the rear and left a 1/2 inch gap on both sides. This was almost identical to the openings of rear prior to shortening them. We debated on changing the size and location of the openings (maybe top and bottom), but decided since they came with openings at 3 and 9 o'clock, we would replicate the size and placement of the openings. The hard part was finding a welder who was proficient at stainless steel. Had a few welders turn down the work.

Doug

US1 Fountain

iTrader: (1)

This is what Corsa did to my Gils when sent in to be shortened.
If you don't have a large enough gap, your WP will go thru the roof w/o any other means of a dump. Needs to have enough of a restriction to get a full fill of the pipe to keep the outer pipe cool.
Also, Corsa only welded the rod to the inner pipe. I added the weld to the outer pipe to tie them together to rid the rattle. I don't believe you want a solid weld as the inner and outer pipes will expand/move at different rates do to different temps the each see. Hence the reason of Corsa only tacking to the inner pipe. I figured by keeping my weld at a distance from Corsa's weld, the rod will flex enough to allow the pipes to be somewhat independent of each other. Never did see if my added weld stayed in tack.
BTW, a 5yr old can weld SS with a Tig. Easiest weld there is in my opinion.

monsta

you could also weld them shut completely and weld in a bung 1/2"p and dump the water over board via a thru hull. Ive done this many times and if you can handle it the noise although loud is AWESOME. AKA dry exhaust.

offthefront

iTrader: (1)

I am installing these on my 311 and they are too long ..3/4" shy of going thru Transom ..they will dump into silent thunder box ....we are extending them out 4" with SS flex house with extenal flappers ...

KNOT-RIGHT

38KV If you are using the Bassets this is how the Tailpipes were originaly.
with the exception of a 1/4 inch hole drilled in the very end.

Never was able to reach Jasper. Could still use a set. of those Bassets

Gerry

mcollinstn

Stainless is definitely the easiest weld in town. Flows like candle wax, and almost REFUSES to oxidize.

Your "gaps" need to be up high like your sketch to keep water around the inner pipe.

Tubes will expand at different rates due to heat.

I advise rolling some 3/8 OD stainless tubing into a donut that matches the OD of your outer pipe. Then belt sand the donut until you make a C shape thru the cross section. Then weld it on.

38KV

Thanks for the great answers!
Gerry, I am using the Bassets, I just have to shorten the tail pipes and was thinking of making it easier than make new flares.

BTW, I'll keep my eyes open and let you know if I find a set.

mcollinstn, Great idea, Thanks! Takes a lot of belt sanding though...


Jonas

offthefront

iTrader: (1)

Mc ...the ring goes all the way around ? If so where does the water exit ? ok think I got it ....gaps ? Also ......seems like mine and the others the two pipes are welded all the way or almost with no worries about differental in expansion ...

mcollinstn

No, not all the way around, unless you weld in a bung. Water gotta get out.

Welding both pipes requires a filler of some sort. A solid bar invites thermal cracking over time. The tubing gives the expansion a place to do its thing. Also gives smooth finished look to the end, as opposed to the "hazardous" looking raw end on some.

Belt sander with 6" wide x 48" long 36 grit belt will gnaw that gap into the tubing in about 15 seconds. If you don't have access to a beltsander and want to do this, send me the loops and I'll bet sand them for a beer coupon or something.