Getting a bit miffed about that Raceco exhaust can

[slomove]

Admittedly the exhaust has some 30,000 miles on it but during its life I had to repack it 3 times and weld cracks around the inlet tube twice.

Now I had an internal blow-through where the titanium shell developed a large blue blotch. Well, thought I repack it just another time and found the inner perforated tube is losing the stainless mesh sleeve. Obviously intended to keep the packing from blowing out and extend its life but now the screen itself is blowing out.

While I still like the good noise reduction but I think for the money it should be a bit more durable (or for the durability it should be cheaper). Oh, well.

[Sean]

Gert - Sorry to hear this. Do you have your headers wrapped? I have read on BC (or somewhere?) that due to the relatively short distance between the hot combustion chamber and the silencer on a Seven, they are prone to burning out the packing material more quickly than other cars, and that the degradation of the packing is accelerated by wrapping the exhaust because that increases the temperature at the front of the silencer. Maybe that's just a lot of "hot air" :D:rolleyes:, but it sounded logical to me. I am curious if the area where the screen has been damaged is the hotter front part of the silencer?

[slomove]

Well, the headers are wrapped indeed. But for whatever reason the damaged section is next to the exit of the can. So I don't think it is a temperature issue. Maybe rather condensate corrosion and fatigue?

[GWise]

Well, the headers are wrapped indeed. But for whatever reason the damaged section is next to the exit of the can. So I don't think it is a temperature issue. Maybe rather condensate corrosion and fatigue?

Gert,

Not knowing the design of the Raceco intimately, could damaged section have been swapped to the rear during previous repacking? I see this sort of failure all the time with my kart. The stinger (perforated tube in your case) always seems to fail where and when the packing starts to deteriorate. The solution I've found is just to repack more often as a preventative measure.

[slomove]

Interesting...but no, I did not reverse the inner tube. Actually when I repacked previously I did not actually "re-pack" completely but just "top off" which means push the remaining packing to the back and fill in new packing from the front. Now that I removed everything I do find some of the packing quite lumpy.

Does this contribute? Maybe, don't know. But the mesh shroud is really superfine thread wire cloth. It does not take much corrosion to eat it up.

For now I am good. Actually when I received the can 6 years ago it had a crushed inner tube (too long) that was replaced free by Raceco. I saved it and beat the crumpled parts straight. Just waiting for more packing material and then I should get it back together.

[moosetestbestanden]

The question not asked is... How has it been over the years, and do (did) you like it - how it sounded, looked etc.

And how would a different one have held up under identical circumstances.

Ya'll know that I know him so...

Write Ammo and ask him to send you the new bits you need.

Nothing lasts forever, particularly when well (and I do mean well, knowing how you've used and enjoyed your car over the fair number of years that the can has been on it) and truly used.

Cheers!

[magnusfeuer]

Gert,

I think you, long ago, mentioned that you ran lean while cruising. Is it possible that you produced exhausts hot enough to cause the damage?

/Magnus F.

[slomove]

Well, yes and no. The fueling was a bit screwey in both directions for a while but not THAT bad. Probably better than with any real life carb.

Since I fixed my misreading wideband gage I am spot on. Maybe I just had a Monday muffler.

[JohnCh]

From this recent thread on WSCC.

I did mine with the Competition mat and They (Savaguard) advised NOT to use stainless steel wire wool around the perforated tube as it can cause "localised hot spots if it moves.."

Perhaps it moved when you did an earlier repacking?

-John