quadrajet plumbing question

[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

[Danny Ashley]

If you want to see how the quickest Quadrajet equipped Super Stocker on the planet plumbs his, check out Don Kennedy's thread----Let it all hang out in Vegas GT/AA page 6. Definitely works for them! Congratulations to Frank and Phil on your Shoot-Out win! Danny

[Mike Voth]

Wow. We haven't been able to run that style regulator in many years! The automatic beast is definately different than the stick shift beast.

[Paul Merolla]

Originally Posted by Danny Ashley

If you want to see how the quickest Quadrajet equipped Super Stocker on the planet plumbs his, check out Don Kennedy's thread----Let it all hang out in Vegas GT/AA page 6. Definitely works for them! Congratulations to Frank and Phil on your Shoot-Out win! Danny

You lost me, Danny. That looks nothing like what you're describing.....

[Danny Ashley]

Paul- One thing I've learned in the Q-Jet business is that everyone's car is different and some things are not set in stone. I still believe the system I described is ideal because the y-block set-up acts as a reservior for more available fuel to the carb., and mounting the regulator in front of the carburetor allows inertia to work for you pushing the fuel into the carb. I know that Phil is really high on the brand of fuel system they run and that may have something to do why their system works as well as it does. Maybe someone else's pump and regulator wouldn't work with this plumbing arrangement. You must understand that needle & seat size, bowl volume, line size, and fuel pressure all contribute to an effecient fuel system. Obviously, Phil and Frank have everything working together to perfection. Hope this helps. Danny

[Buicksstage1]

Hi, my name is Chris and i'm new here. We are building a SA car so everything has to look stock right down to the pump, carb fuel etc. I have a spare BG400 and reg, keeping in mind that regulator/lines all have to be hidden and stock looking how would you guys build this return fuel system. I'm gutting the stage1 pump and installing a bypass in the can part off the pump, Thank you........ Chris Skaling

[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.

[Bob Gullett]

Sort of a little off topic but I'm sure Danny will agree that no 2 carbs are the same. You could take 2 new carbs, do the exact modifications to them and one of them seems to always be a little faster or one could be a complete dud. We have modified a new quadrajet that is not as fast as a crusty old carb that is 30 years old. Thats the way things go. If you can find a good carb, keep it.