Jerry Hey wrote:

Paul,  what are the maximum temperatures the  intake (in the
housing)
will see?   I am selecting the epoxy to bond in the P port throttle
bodies.    I did contact Racing Beat to see what they used.  It is
Devcon but which specific product I could not find out.   I bought
what
the sales person "thought" they used but it is a repair material
about
as thick as peanut butter.  I want something that can be poured
and is
self leveling.  If WEST can tolerate the temps,  I may go with
that.
I
am open to advice from anyone.       Jerry

Epoxy works great. The temp is limited to about 200 F heat soak.
When running it is cooler. There are some high temp epoxies that
work
at
300 F.

Paul Lamar

My search has led  to " Duralco 4525" an epoxy with metal filler that
is stable to 500 degrees.  Said to be ideal for high performance
bonding, potting. repairs, castings and jigs.  Will not crack with
differential expansion of the aluminum housing due to high aluminum
content.   Machinable.   I will call them this afternoon.    Jerry

     Sounds like Tracy's favorite substance...  JB Weld :)

     Paul Lamar

Jerry,
The material does indeed sound like JB Weld. Which is an epoxy with
an aluminum, and other fillers.
 I like the periferial port idea Jerry. I have one other suggestion
as well. If you cut the housing with a slight taper, (small at the
outside), around .005
and match with the stub on the throttle port you can use differential
heating to lock the port in very well. Still use the epoxy, it will
then be functioning
as a sealer more than a mechanical bond. Liquid nitrogen is usually
available from industrial sources. Lacking that, get dry ice from a
local source, and pack
the stubs in it for 1/2 hour and oven heat the housings to about 200.
put your epoxy on the cold part then insert. be sure to line up the
throttle shaft bores
and stick the parts togeather. You will get a super bond and seal.
Good luck Jerry,
Bill Jepson

That is a good idea.  However,  the throttle bodies have been made for
a couple of months and they are not tapered.   I am not worried about
holding the inserts in place.  They are keyed and will have mechanical
lock.  I just want the epoxy to behave at high temps.   I called WEST
and they said their epoxy becomes rubbery above 140 degrees.    I have
ordered the good stuff about an hour ago.    Jerry

 
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