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Lobby / Re: leaf spring traction
« Last post by lightning boy on May 23, 2024, 01:38:02 PM »Okay, thanks Cliff!
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Quadrajet Parts and Numbers / Re: 73 Z-28 7043213
« Last post by MRSOFTE on May 22, 2024, 09:45:00 AM »Oops, I have a (704) 3213 not a (714) previously stated.
yes the NOS one I did locate would have the nipple facing away. Its first three numbes start with the same #'s as my 704 carb. So maybe that means something. Or its just coincidence?
Bought from you before Cliff and soon I will order your full rebuild kit.
yes the NOS one I did locate would have the nipple facing away. Its first three numbes start with the same #'s as my 704 carb. So maybe that means something. Or its just coincidence?
Bought from you before Cliff and soon I will order your full rebuild kit.
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Quadrajet Parts and Numbers / Re: 73 Z-28 7043213
« Last post by Cliff Ruggles on May 22, 2024, 02:27:34 AM »Not sure about NOS. I have a few of the original type pull-offs for those. Some of them had the vacuum nipple facing away from the carburetor, your 1973 may have been one of them.
I do stock jets and metering rods for them, and the correct Power Piston spring, plus the best rebuild kit in this industry with the high-flow N/S assembly and lifetime warranty on the accl pump......
I do stock jets and metering rods for them, and the correct Power Piston spring, plus the best rebuild kit in this industry with the high-flow N/S assembly and lifetime warranty on the accl pump......
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Quadrajet Parts and Numbers / 73 Z-28 7043213
« Last post by MRSOFTE on May 21, 2024, 10:52:50 AM »The vaccum break has been replaced on my 7143213 , I'm searching for a correct NOS one. Where can I go to find the correct part #? Or perhaps somebody knows?
Also I know it has 76 jets and 45 rods installed, modified from stock which would of been 74/44.
Any suggestion for jet/rod for my altitude of 5000 ft?
Thank you.
Also I know it has 76 jets and 45 rods installed, modified from stock which would of been 74/44.
Any suggestion for jet/rod for my altitude of 5000 ft?
Thank you.
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Diagnose a Quadrajet carburetor problem / Re: 7041540 Buick 455 goes lean at WOT
« Last post by Cliff Ruggles on May 21, 2024, 05:59:56 AM »So I said 6 but it could have been 7, it was regulated for Quadrajet use on the dyno and feeding the carb direct.
Even with a small float and .145" seat those carbs will EASILY take 8-9 PSI fuel pressure w/o issues.
When you reduce fuel pressure you kill volume to the bowl, especially since all of it has to pass one N/S assembly.
The rumor or myth that Q-jets can't handle high fuel pressure comes from the early designs with the short hinge pin and huge float. Those are tough units to keep full and will give troubles with higher fuel pressure and larger fuel inlet seats.
First thing to do when you go lean at WOT and high RPM's is to kick up the fuel pressure. If that doesn't get it install a larger N/S assembly until the problem goes away. If you can't correct it with those moves fuel delivery is not adequate for the power level.
I'd also add here that you MUST have adequate fuel delivery and keep the bowl FULL on hard runs before any tuning can be done to get the A/F where you need it to be.......
Even with a small float and .145" seat those carbs will EASILY take 8-9 PSI fuel pressure w/o issues.
When you reduce fuel pressure you kill volume to the bowl, especially since all of it has to pass one N/S assembly.
The rumor or myth that Q-jets can't handle high fuel pressure comes from the early designs with the short hinge pin and huge float. Those are tough units to keep full and will give troubles with higher fuel pressure and larger fuel inlet seats.
First thing to do when you go lean at WOT and high RPM's is to kick up the fuel pressure. If that doesn't get it install a larger N/S assembly until the problem goes away. If you can't correct it with those moves fuel delivery is not adequate for the power level.
I'd also add here that you MUST have adequate fuel delivery and keep the bowl FULL on hard runs before any tuning can be done to get the A/F where you need it to be.......
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Diagnose a Quadrajet carburetor problem / Re: 7043251 set up advice
« Last post by Cliff Ruggles on May 21, 2024, 05:52:31 AM »72 jets are huge in one of those carbs if you still have the stock MAB sizes. They are typically fine on mild builds with 69 or 70 main jets in them.
Some will act a little lean at light load with the 48B's in them. I remove the factory APT screw and replace it with an adjustablle screw that I make and sell here. This allows for full control of part throttle A/F without taking the carb apart.
Haven't seen a 455 yet that didn't enjoy some idle bypass air and not sure why it would be blocked?
Was the carburetor commercially "remanufactured" at some point?
Is the steel post still on the bottom of the power piston?....
Some will act a little lean at light load with the 48B's in them. I remove the factory APT screw and replace it with an adjustablle screw that I make and sell here. This allows for full control of part throttle A/F without taking the carb apart.
Haven't seen a 455 yet that didn't enjoy some idle bypass air and not sure why it would be blocked?
Was the carburetor commercially "remanufactured" at some point?
Is the steel post still on the bottom of the power piston?....
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Quadrajet Carb Talk and Tips / Re: 17057216
« Last post by Cliff Ruggles on May 21, 2024, 05:47:08 AM »Rebuild kits are here:
https://cliffshighperformance.com/product-category/quadrajet-rebuild-kits
They are the most complete/correct in this industry and the ONLY kits that come with a lifetime warrantly on the accl pump seal.
I also include the .135" fuel inlet seat and you can substitute .140:, .145" or .149" at no additional cost.
Each kit is also built exactly for your carburetor and needs. So you will only get the gaskets and parts required for your carb number and not looking at a bunch of gaskets that don't fit or work for what you are doing.....
https://cliffshighperformance.com/product-category/quadrajet-rebuild-kits
They are the most complete/correct in this industry and the ONLY kits that come with a lifetime warrantly on the accl pump seal.
I also include the .135" fuel inlet seat and you can substitute .140:, .145" or .149" at no additional cost.
Each kit is also built exactly for your carburetor and needs. So you will only get the gaskets and parts required for your carb number and not looking at a bunch of gaskets that don't fit or work for what you are doing.....
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Lobby / Re: leaf spring traction
« Last post by Cliff Ruggles on May 21, 2024, 05:43:40 AM »No pics, sold the car about a year ago.
You are basically making a box with shims to move the rubber snubber closer to the diff.
For Mopars they used to sell one that bolted to the diff with the snubber moving upward which was really a nice part.
I made a bunch of shims for mine from flat bar, not really all that difficult.
What you are trying to do is to control diff "wind-up" when the tires hook. Going to the center of the diff is a LOT more effective than bars clear out at the ends of the axle tubes and the suspension still appears "stock" at a glance....
You are basically making a box with shims to move the rubber snubber closer to the diff.
For Mopars they used to sell one that bolted to the diff with the snubber moving upward which was really a nice part.
I made a bunch of shims for mine from flat bar, not really all that difficult.
What you are trying to do is to control diff "wind-up" when the tires hook. Going to the center of the diff is a LOT more effective than bars clear out at the ends of the axle tubes and the suspension still appears "stock" at a glance....
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Lobby / 350 vortec crankshaft info
« Last post by quadrajam on May 15, 2024, 06:34:08 AM »Does anybody here know or can find out the target bobweight of a 350 vortec
crankshaft? Keep in mind there are 3 different 350s and 1 305 crank that have
the same casting number. What I need to know is bobweight for the vortec crank.
Thanks
QJ
crankshaft? Keep in mind there are 3 different 350s and 1 305 crank that have
the same casting number. What I need to know is bobweight for the vortec crank.
Thanks
QJ