My oar on exhaust wrapping

[kirby.a.smith@lmco.com]

Failing to resist the urge to contribute, as my common sense dictates, 
I offer the following factoids to the discussion about wrapping and 
coating exhaust parts.

On the turbocharged Corvairs, which have horizontally opposed 6 
cylinder engines with one turbo above the right bank, the exhaust from 
the left bank is brought over the the right via a mild steel pipe 
routed roughly below the bell housing, more or less directly in the 
breeze below the car.  It is a significant aid in apparent torque to 
wrap this pipe with aluminum foil covered ceramic insulation.  Kits 
for this have been available since 1967, at least.  Claimed horsepower 
gain was 15 (over 180 hp stock).

The long term effect of wrapping the pipe was deterioration of the 
steel temper to an eventual point of brittleness.  As this pipe was 
relatively inexpensive, and easy to access, this was not considered a 
problem.  Note that the location of the exhaust manifolds themselves 
precluded wrapping them unless engine cooling (and passenger heating) 
was to be degraded.  Interior ceramic coatings were not available to 
my knowledge at the time the wrapping was commonly employed.  (Which 
is not to say I'm not interested for the future.)

I also can't resist noting in passing that the exhaust manifolds were 
connected to steel tubes mounted in the aluminum head exhaust ports.  
The manifolds were retained by 3 steel clamps held on by three nuts on 
3 studs.  Stud breakage due to thermal expansion was unheard of!!!!  I 
will resist comparing the time required to remove and replace a 
Corvair exhaust manifold with that for my Audi, which recently cost me 
more than the shock absorber upgrade I would have rather spent the 
money on.

***                 ...Kirby    (Kirby A. Smith)                 ***
***                      2 X 1988 90q                            ***
***              ksmith1@mailgw.sanders.lmco.com                 ***
***              [=]   kirby.a.smith@lmco.com                    ***
***  Opinions expressed herein are entirely those of the author. ***