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Re: [T3] vapor lock cont'd

Well, here are the issues with the OTT muffler systems and headers in
Its pretty well know that they are "Bellows burners" as even with a little
clearance between the muffler and bellows  there is NO heat shield like the
stock mufflers have so the heat is exposed right to the bellows.
    The other issue is surface area of hot exaust IN the engine compartment,
with all those tubes running around with a header you have alot more surface
area under there (pre muffler) than you do in a stock setup with heater
boxes that are nicely wrapped in not only cool air but insulation.  THEN you
add a muffler without a heat shield and you tend to make the matter even
worse especially with hot J tubes right under the heads. The OTT muffler is
especially bad as it is large and up high, whereas a stinger or glass pack
has MUCH less surface area to transfer heat to the engine compartment air.
When looking at Ron's OTT setup from Kymco last month, I noticed that that
muffler looked like it *may* have had a heat shield integrated into it, this
would help.

The saving grace is that unlike the beetle our engines suck fresh cool air
from outside the body, but still... introducing heat to the engines
surroundings is counter productive.


> I do have an over the top (ISP West version, painted with POR hitemp
exhaust paint) which is almost identical to a single extractor, except it's
inverted and the muffler is a bit smaller. Everything is under the bellows,
and there is still plenty of clearance between the top of the muffler and
the bellows (like 2 inches). I'm not sure how much more heat this unit could
generate as opposed to other extractor systems (?) but the slight problem
I'm still having seems to imply the post shutdown heating of lines/pump
and/or a blockage in the metal chassis line (it's still hard to start when
hot and then parked for 10-15 min, although I can always get it started, and
it doesn't skip a beat once running). Here are a few photos:
> http://dcr.csusb.edu/dny/img_9075.jpg
> http://dcr.csusb.edu/dny/img_9077.jpg
> http://dcr.csusb.edu/dny/img_9084.jpg
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