-------------- Original message from George Graham <rx7ez@yahoo.com>: --------------


>
> I made a nice intake manifold, that is still working well after
> almost seven years.
>
> I started with a three inch square aluminum tube, 1/8 inch
> thick,
> about one foot long.
>
> I cut the holes to match the engine intake ports, and the
> carb base on the top. One of the mount holes goes through the
> square tubing, the other three bolts just clear the outside
> edges.
>
> I filled the tube with urethane foam insulation board, two
> pieces
> one, one inch thick, the other two. I then carved the ports and
> runners in the foam, and glassed them with two plies. The foam
> supported runners then slide in the end of the support tube,
> and I sealed the ends (I used fiberglass, but aluminum would
> work better).
>
> I did reinforce my carb flange studs, with 1/2 inch wide by 1/8
> inch thick steel strips, which were tapped for the studs.
>
> I worried about the exhaust being too close to the intake
> for fiberglass alone.
>
> I have plenty of that tubing, if anyone wants any.
>
> George Graham
> Mazda Rx7ez N4449E
> Homepage