Van,
Don't you have an Etec

I thought they sipped gas? Let me tell you about my 350 Carborated Chevy.
Toys like that sound cool but it is pricey. I think maybe $600. A freind of mine has one, it worked for a couple of years and hasn't worked right for about 5 now, it came with the boat when he bought it, used.
So I'd say save your money, $600 will buy more gas! Go buy feel and sound. On my boat I can tell when the secondaries open up and if I'm just messing around I take it easy.