Anyone here ever built a Flowbench?

Buying one right now is out of the question. But I'd like to get into porting heads, intakes, etc... for a little extra side money.
I've ported a couple heads before, but without a bench I really don't know the true effects of the work. The seat-of-the-pants meter usually tells me it's good, but if I were to sell a set of heads to a customer, I'd think they'd want to know what those heads are really flowing. I know I would.

I've heard of people building their own benches before and just wondering what the cost involved would be, and whether it's worth it...

[addsig]

i did not do this but it seemed cool at the time- about 1977 car craft magazine built one using a cheap manometer and a shop vac- i think they spent like 50 bucks and it worked!if memorey serves me it was in conjunction with valley head service who they seemed to pushing at the time.if yu are going to the micro fim it could b as early as 1975 as vans and gas mileage were big topics-could one of you whipper snappers hand me my geritol

here's a link to building an actual flow bench. Takes a little cash though if you build it the same way. It could give you a few ideas though. I built one with a Shop vac and a vaccum gauge. Any improvements cause a drop in the vaccum reading. This doesn't give you flow in cfm, but you can calculate the improvement in percentages.

http://www.diyporting.com/flowbench.html


Nathan