quadrajet plumbing question

[wickedmalibu]

my question is about using a bypass regulator. this is a new thing to me, can i set the car up with the bypass in front of the carb with a AN flare tee then run the return line back to the tank? any help would be helpful....

[Mike Voth]

We use an Aeromotive regulator that is mounted up front, behind the passenger side headlight. Two outlet lines to a 'Y' that feeds one line to the carb. We have a return line that comes directly from the regulator back to the tank. The "Y" block has another outlet that we have a pressure gauge screwed into. 4 psi does the trick for us. If you're already familiar with the q-jet, you know that there is limited bowl volume. We have the pump pressure at it's maximum so we don't lose any volume during the launch. If we don't run maximum pressure, then the fuel in the line to the regulator stalls and actually runs the bowl dry. This might be different for an automatic. Hope this helps.

[Dave Goob Cook]

I wonder how it would be to place the regulator after the carb inlet?
You would lose no volume through the regulator, and bypass the excess back to the tank.

[Mike Voth]

Dave - Do you mean running full pump volume to carb, then regulating the rest back to the tank? Q-jets are finicky. They bubble over with too much pressure.

[Danny Ashley]

The regulator location and plumbing that Mr. Roth has on his car is, in my opinion, the best way to feed a side outlet Quadrajet (assuming that is what he uses). However, the best situation, again my opinion, is to use a late model, front outlet Q-Jet with the regulator mounted directly in front of it, using both outlet ports to a y-block, then to the carburetor. The 75' and later Q-Jets have more float bowl volume because of the aneriod cavity and the front outlet eliminates the severe 90 degree turn the fuel must make before the needle & seat in the side outlet carburetors. You can and should do some work on the side outlet Q-Jets to help the fuel turn the corner. This set-up is hard to do on Chevy combinations in Stock because of the thermostat housing but the carb spacers and taller manifolds in Super Stock make it doable. Hope this helps. Danny @ Q-Jet Performance

[Danny Ashley]

Sorry, it's Mr. Voth. My bad

[Mike Voth]

Originally Posted by Danny Ashley

The regulator location and plumbing that Mr. Roth has on his car is, in my opinion, the best way to feed a side outlet Quadrajet (assuming that is what he uses).

That's what we use. We haven't been able to get the front inlet q-jet to run as good as the side inlet q-jet, for what ever reason.