Alternative stainless rear box, any ideas?

[thor]

So...I've now ordered a replacement SS back box for my S130 from the helpful Susan Miller,but apparently it doesn't look like the Sprint one on the picture, with the upturned rear pipe. Anyone have a photo of what the Sue Miller one looks like ?

[twincamman]

I use cherry bombs 18 bucks Can sounds like an f2 car ----or also tractor mufflers work ----but the harrow slows one down slightly ---ed

[thor]

Lovely rear box fitted from Susan Miller, larger rear pipe than the one I had, and VERY quiet...Not sure I'm altogether happy about that , and unfortunately all the charming backfiring seem to have dissappeared also... shame.
This because the battered main pipe was completely loose inside the connection to the downpipe. I've fitted the system a lot closer to the body than on the Sprint picture on this post, not a good idea. Will hang it further down. Also a Bad vibration from where the clamp touches the gearbox by the downpipe, after I replaced the cracked shit hoseclip holding this connection together.
It seems that at this point there's absolutely NO space for a normal clamp, so I've bought two stainless super heavy ratchet hose clips. Bad idea?

[schroeder]

Thor

Very surprised that the clamps are touching the gearbox. I can only assume that you have the box very high. The center pipe and silencer pipe have bends and thus by rotating the center pipe will raise and lower the silencer to some degree.

My system is only mounted to the car via the rear box at three locations (and of course the exhaust manifold bolts). Two rubber bobbins at the front and a strap hanger at the rear. The bobbins will set the clearance from silencer front to body, rotate the center pipe with all the joints loose to get the system in the right place and use an appropriate length of strap at the rear. Then simply tighten the joints. I've never had a problem with U-Bolt clamps.

One other thought, when I first bought the car it had a morris minor silencer, (Not Recommended). I replaced it with a PECO silencer. This had an integral bracket to which the bobbins fitted.

Many years later I got a SS silencer from Paul Matty. Very nice but no integral bracket. The parts manual shows the bracket seperately. Not sure about the Sue Miller design.

Hope this helps

Stu

[thor]

The centre pipe is a bit (a lot!) war scarred, so I have a suspicion it's been grounded in the past, hence the higher position due to the downpipe joint being pushed up.- MINIMAL clearance to the gear box. Or because of the Spyder spaceframe?
I need to redo the clamps at the back to lower it a bit (currently hanging optimistically high 4mm under the heat shield), at that might do it.
If I twist the pipes the back box ends up not hanging level, which I found really annoying with the old one. Hope I can do it with remaking the hangers on the back and fitting a smaller clamp to the downpipe joint. And must also remember to move the nuts of the clamped joint before the box to ABOVE the pipe.....

[schroeder]

Thor

4mm, That is close. I have about 2 3/4 inches of clearance, about 70 mm. I have taken several pics. Thought they may help. Now if I can just get them to load?

Better Idea. I will send you a pm with the pics.

Stu

[thor]

great!

[schroeder]

Thor

Did PM's with Pics arrive? Had some trouble but thought they went. Six shots in all

Stu

[thor]

No, didn't get them I'm afraid. Think I've sussed it now, sideways clamp on the front now about 2-3mm from the gearbox, and the downpipe doesn't move much.
Hung it about 70-80mm down on the back, had to make/hammer/bend new homemade brackets again. And then finally down on the wheels, no vibration, but CLANG CLANG CLANG CLANG CLANG on a rough unwarmed idle .... Put the last clamp before the rear box upside down to save the nuts from speedbumps, one of the nuts ended up 2mm from the underside of the chassis, not a good idea. Up with the car, back on with the suit, and turned the bracket sideways. Now it's perfect.

And the backfiring hasn't altogether gone, just a lot quieter, wouldn't want to lose it altogether....