quadrajet plumbing question

wickedmalibu · 10-31-2008, 09:56 PM

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 · 11-01-2008, 12:55 AM

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 · 11-01-2008, 08:42 AM

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 · 11-01-2008, 08:58 AM

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 · 11-01-2008, 12:31 PM

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 · 11-01-2008, 12:32 PM

Sorry, it's Mr. Voth. My bad

Danny Ashley · 11-01-2008, 07:19 PM

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 · 11-01-2008, 10:40 PM

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 · 11-02-2008, 09:22 AM

Quote:

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 · 11-02-2008, 10:27 AM

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

10-31-2008, 09:56 PM	#1
wickedmalibu Junior Member Join Date: Aug 2007 Posts: 19 Likes: 0 Liked 0 Times in 0 Posts	quadrajet plumbing question 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....

11-01-2008, 12:55 AM	#2
Mike Voth Live Reporter Join Date: Jun 2008 Location: Buhler, KS Posts: 527 Likes: 5 Liked 57 Times in 14 Posts	Re: quadrajet plumbing question 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. __________________ Mike Voth 5189 GTN - 5188 GTO Voth Racing Last edited by Mike Voth; 11-02-2008 at 06:33 PM.

11-01-2008, 08:42 AM	#3
Dave Goob Cook Member Join Date: Dec 2006 Location: Indy Posts: 422 Likes: 0 Liked 0 Times in 0 Posts	Re: quadrajet plumbing question 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. __________________ "Despite the high cost of living, it remains popular." Dave Cook NHRA N375

11-01-2008, 08:58 AM	#4
Mike Voth Live Reporter Join Date: Jun 2008 Location: Buhler, KS Posts: 527 Likes: 5 Liked 57 Times in 14 Posts	Re: quadrajet plumbing question 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. __________________ Mike Voth 5189 GTN - 5188 GTO Voth Racing

11-01-2008, 12:31 PM	#5
Danny Ashley Member Join Date: Nov 2001 Location: Marion,In. Posts: 267 Likes: 60 Liked 110 Times in 29 Posts	Re: quadrajet plumbing question 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

11-01-2008, 12:32 PM	#6
Danny Ashley Member Join Date: Nov 2001 Location: Marion,In. Posts: 267 Likes: 60 Liked 110 Times in 29 Posts	Re: quadrajet plumbing question Sorry, it's Mr. Voth. My bad

11-01-2008, 07:19 PM	#7
Danny Ashley Member Join Date: Nov 2001 Location: Marion,In. Posts: 267 Likes: 60 Liked 110 Times in 29 Posts	Re: quadrajet plumbing question 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

11-01-2008, 10:40 PM	#8
Mike Voth Live Reporter Join Date: Jun 2008 Location: Buhler, KS Posts: 527 Likes: 5 Liked 57 Times in 14 Posts	Re: quadrajet plumbing question 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. __________________ Mike Voth 5189 GTN - 5188 GTO Voth Racing

11-02-2008, 10:27 AM	#10
Danny Ashley Member Join Date: Nov 2001 Location: Marion,In. Posts: 267 Likes: 60 Liked 110 Times in 29 Posts	Re: quadrajet plumbing question 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