Air filter box. Aluminium or steel?

JP147 · Post by **JP147** » Thu Oct 23, 2014 8:50 pm

I have been using that little open chrome filter on my Weber 32/36 and it was good in the winter. Now in the summer, the carb is getting too hot when the car is not moving.
I will adapt the stock blue filter box to fit the carb with a hose taking air in near the headlight. I have cut the bottom out of one and will make a new bottom out of metal.
I need something that will insulate the heat from the engine well, but I am not sure if steel or aluminium will be better for keeping the filter box cool.

steptoe · Post by **steptoe** » Fri Oct 24, 2014 7:07 am

try to get some of the aluminium waffled sheeting heat shield found under many cars installed as exhaust heat shield along the floor - it is so excellent !

T.Farm.Brumby · Post by **T.Farm.Brumby** » Fri Oct 24, 2014 2:51 pm

Aluminium every time, whatever you can get really, it pretty much all acts as a heat-sink.

+1 for the sheeting Steptoe.

If you can get away with it, rip some headunits apart, they all have a nice big chunk of aluminium on the ass end that you can hack the teeth off, which acts wonders, also easy to work with if you have a decent grinder wheel.

Also, the CPU fans from computers are made of a nice aluminium alloy if you can get your hands on some, plenty of "blades" on them that you can sandwich together. Air gaps between them act as extra insulation as well (think voids in asbestos insulation).

Cheers,
Tom.

EDIT: PS. if you're sandwiching the fan blades together, it's pretty structurally pitiful, mostly just for thick insulation.

YouTube · Post by **El_Freddo** » Fri Oct 24, 2014 11:04 pm

If you're talking about what metal to use in the air box to make it fit the weber I'd go the sheet metal (steel).

IMO the aluminium would quickly/easily heat sink and transfer this to the air in the air filter.

Plus you can't weld aluminium to steel as far as I know...

Cheers

Bennie

JP147 · Post by **JP147** » Sun Oct 26, 2014 11:07 pm

So I made this thing. It is a bit rough, but I didn't have much time or tools and it does the job. Maybe with the body lift I will be able to fit an adaptor to put a normal Subaru airbox on the weber.

I glued some insulation foam that is used for boat engines or something on the bottom. It is silver underneath and lets no heat through, keeping the bottom of the box very cool even when everything else it hot.

Later on I might put a hose on the intake leading near the headlight for extra coolness.

YouTube · Post by **El_Freddo** » Tue Nov 11, 2014 9:04 pm

That's pretty neat and looks easy to do!

Now all you need is an inverted V piece of flat bar that is mounted to the two outer lid retainer nuts with the third one mounted in the middle at the top point of the V

That'd complete the three bolt retainer nut factory look!

Cheers

Bennie

Tweety · Post by **Tweety** » Tue Nov 11, 2014 9:16 pm

That looks fine. Out of sight out of mind. And its functional.

No need to feel guilty that it looks "rough". Looks good to me