Just a word of caution here for those of use running a non-vented fuel sys with EVC. Short story is that if u top of the fuel tank u'll also fill up ur charcoal canistor with fuel.

Ok the long story:
I spent a few good days installing a recirc from the fuel bowl itself back to the tank with a orifice restiction only - no regualtor. Well my new Carter street pump works great and i read 6-9 psi right from the cockpit as i tee'd off the fuel bowl with an electric (Holley $70) press sender (the other tee end for recirc). No regualtor here as the Carter has internal reg for 6-8psi and works great (as most mech pmps do).
Problem happened when i topped off the fuel tank. Well i started to get black smoke and studder right away. Then while at idle with hood open raw fuel was flowing out under driver side of eng comp - bubbling out of EVC. More than a little embrassing as an old vette with the hood open always attracts onlookers. :o
Anyways my guess is that with an unvented sys as the car leaned enough to drivers side the tank now pressurized with 6-9psi forced fuel right past my liquid/vapor separator. I had dissasembled and tested the separator - but only with water in the sink - when i recently replaced the fuel tank but my guess is that it really can't handle 6-9psi as it's just a small float/ball type inverted vlv.
And yes i had just replaced the $52 charcoal cannister. And now NAPA wants $80.
To get back on the road i just removed the fuel tank cap and reved to hi rpm to clear out the what-ever. Hey does this give me bragging rights to the first coal powered corvette???

My fix for now is to run a vented cap, EVC disconnected, until i can find a better lquid/vapor separator - well no-one sells replacements anyways so a search for a donor vehical is due. I would have saved myself a lot of effort by just staying with stock pump and return as that would have been enough for my little 350" combo. But i had wanted to run a non-vented sys with recirc and electric press gauge to monitor because recirc makes a lot of fuel vapor. At least now i know the fuel press right at the needle and seat.

Mr.Wave r u using vented or non-vented sys? Through EVC?? Becareful! If u can c flow waves u b making a lot of vapor. BTW i installed a .050" orifice (drilled brass at the tee) to reduce the return flow.

Well the good news is that carb lars rebuilt for me is working great. Without choke i just rev to 1200rpm for only 30sec and it idles smooth. No adjustments other than to match rpm for idle timing - never touch idle screws, just bolted her on. Oh one mod i made is i drilled into the front of fuel bowl/filter fitting housing to insert a tee. Drilled, tapped and JB welded tee onto the housing very carefully to prevent chips from entering. But again this was all over kill for my application - just for my peace of mind (well maybe a bigger mtr later).

My 2 pennys: don't top off and leave ur tank vented. cardo0