I’m a total greenhorn when it comes to Rochester Quadrajets, but I learned Holley 4150’s and the like just because it’s what I always had, Holley is very easy to maintain if you don’t disturb the throttle shaft, I would rather not try and repair a bad Holley base an opt for a new one, or whole unit. I need to build my Rochester to accommodate the new 402 Chevy BBC 9.5 to 1 comp. Dual plane L78 type mid rise , solid flat tapper Lunati 515 intake 525 exhaust 108 lobe sep. 104 intake center, 224 intake and 236 exhaust duration @ .050 , Hooker Comp headers, 3 inch exhaust and big block Flowmasters, electronic ingnition. I have a new 1901r candidate. Price please?
where can i find complete power piston assembly...mine was rusted in and destroyed..13:30 these are not reproduced..does that mean i am SOL...I hope not..I cant be first guy needing one.
What jetting, primary and secondary’s do I need for my 87 caprice classic quadrajet for here in TX? Was rebuilt and jetted for Colorado altitude so I need to change that. Any and all advice will be extremely appreciated
Reduce original jet size by one in your case. Quadrajet jetting is typically changed down one size at 5000' and one size lower every 2000' over that. However, keep in mind todays fuel burn faster, so at 5000' stock jetting should be good.
Each carb code was calibrated for a specific application and fuels back then. If engine is changed, or carb moved to different than original engine, it needs to be calibrated and jets are one step to that. Also, with todays fuels, a stock carb can use a size larger in jets than original to allow more fuel.
hello my engine builder swapped out my jets not sure the size as the number is all messed up on the top, it had 73 jets, but he did not use the main metering rods what effect will this have ,, i just put the original stuff back to try the difference since the motor has been rebuilt as a starting point
Did this carburetor have the original parts? What type of engine is it usually mounted on? Would it work for an omc cobra 5.0 v8 engine? Can you tell me where I can get the paper you use in some of your videos where the quadrajet models come from to know their jet and primary needle specifications? all the best
I looked up your name and don’t see any orders from you. You must be ordering from somewhere else. All of our rebuild kits include power piston retainer. Order your kits from us next time. We would appreciate your business.
It’s not quite that simple. It’s more about optimizing your engine and once it’s running correctly your mpg’s will be as good as they can get. That being said: quadrajets are pretty much the most efficient 4 barrel carb.
The early seat uses the o ring fitting with 2 screws holding it in place. It will not accept the threaded type seat. We sell the type you need. quadrajetpower.com/early-style-needle-and-seat-with-o-rings/
Thanks for sharing. I like these carbs. Easy to work on and easy to teach
I know how you feel about losing your favorite tool. Mine is my picket screwdriver. I use it in every car I work on!
Great tutorial. I like quadrajets.
Thank you
I’m a total greenhorn when it comes to Rochester Quadrajets, but I learned Holley 4150’s and the like just because it’s what I always had, Holley is very easy to maintain if you don’t disturb the throttle shaft, I would rather not try and repair a bad Holley base an opt for a new one, or whole unit. I need to build my Rochester to accommodate the new 402 Chevy BBC 9.5 to 1 comp. Dual plane L78 type mid rise , solid flat tapper Lunati 515 intake 525 exhaust 108 lobe sep. 104 intake center, 224 intake and 236 exhaust duration @ .050 , Hooker Comp headers, 3 inch exhaust and big block Flowmasters, electronic ingnition. I have a new 1901r candidate. Price please?
where can i find complete power piston assembly...mine was rusted in and destroyed..13:30 these are not reproduced..does that mean i am SOL...I hope not..I cant be first guy needing one.
What jetting, primary and secondary’s do I need for my 87 caprice classic quadrajet for here in TX? Was rebuilt and jetted for Colorado altitude so I need to change that. Any and all advice will be extremely appreciated
I live at 6,000 feet. Do i need to reduce my jet size (one size for each 2,000') similar to Holley? Carb on Chevy 305. Great video!
Reduce original jet size by one in your case. Quadrajet jetting is typically changed down one size at 5000' and one size lower every 2000' over that. However, keep in mind todays fuel burn faster, so at 5000' stock jetting should be good.
Excellent. Thanks for your help!
What would be the purpose of changing the jets in the carburetor? How would you know if they needed to be changed?
Each carb code was calibrated for a specific application and fuels back then. If engine is changed, or carb moved to different than original engine, it needs to be calibrated and jets are one step to that.
Also, with todays fuels, a stock carb can use a size larger in jets than original to allow more fuel.
@@QuadrajetPowerLLC Thank you for responding.
hello my engine builder swapped out my jets not sure the size as the number is all messed up on the top, it had 73 jets, but he did not use the main metering rods what effect will this have ,, i just put the original stuff back to try the difference since the motor has been rebuilt as a starting point
Did this carburetor have the original parts? What type of engine is it usually mounted on? Would it work for an omc cobra 5.0 v8 engine? Can you tell me where I can get the paper you use in some of your videos where the quadrajet models come from to know their jet and primary needle specifications? all the best
15:40 I've ordered 3 rebuild kits from you and they've never came with a power piston retainer
I looked up your name and don’t see any orders from you. You must be ordering from somewhere else. All of our rebuild kits include power piston retainer. Order your kits from us next time. We would appreciate your business.
Is it important to have that plastic cover over the float? My 17058213 carb doesn’t have it
Yes, the float cover is needed.
is there a way of getting better mpg by changing the jets and primary rods?
It’s not quite that simple. It’s more about optimizing your engine and once it’s running correctly your mpg’s will be as good as they can get. That being said: quadrajets are pretty much the most efficient 4 barrel carb.
Hey guys I have a early 66 quadrajet on a 327 and the bowl has a Preston needle and seat I need to thread it because it leaks is there a tap for that
The early seat uses the o ring fitting with 2 screws holding it in place. It will not accept the threaded type seat. We sell the type you need.
quadrajetpower.com/early-style-needle-and-seat-with-o-rings/
Haha you sound like ned Jarrett
Fuel injection will never atomize the air/fuel mixture.