CArb Swap - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Tool · 10-21-2004, 11:50 PM

I just swapped out my old piece of junk Q-jet, with a questionable Holley, I've bolted up the adapter plate, and I've modified the linkage bracket, and I was wonderin about all the vacums, which I haven't started hookin up. Will the all hook back up, or do I need to make any mods to them. I haven't looked at them very closely, and I just didn't want any surprises. I was also wonderin about swappin the old intake manifold, with a holley street avenger, I have, and how colmplicated of a swap that would be.

Tool · 10-23-2004, 02:13 AM

If any body could send me a pic of the throttle linkage of a holley on a 77 gm stock manifold. Any help would be greatly appreciated

badone07 · 10-23-2004, 03:40 AM

I don't presently have a holley on mine, but exactly which model Holley do you have?

Also if you can't adapt, cut/weld up the stock linkage bracket, they do sell adjustable brackets.

Get a set of intake gaskets. If you can set the motor to TDC, dump the coolant, remove the distributor, remove the intake and not drop or lose anything inside the lifter valley, you will be fine. Clean off the intake mating surfaces real well. A razor blade, gasket scrapper and/or a wire wheel on a drill and a can of brake cleaner will do. I don't use the china wall end gaskets. I use a punch to randomly dimple up the end rails and use rtv to seal them up, both on the block and intake. Some people use the intake gaskets dry as is. I use a little rtv around water coolant passages and permatex #2 around fuel. Bolt the intake on after rtv "skins up". Some people torque these down by sequence. I tighten then in sequence by feel, without stressing the intake. Put distributor back in close to where it was when you started. Just tight enough so you can move in either direction. Bolt on carb. Plug vacuum lines other than pcv. Put coolant back in. Start it up and set timing. Then adjust the carb. If you have an automatic, don't forget to hook up the vacuum modulator line. After it's been warmed up, go around and check the intake bolts 1 more time. Then figure out your linkage and vacuum line problems. I might have skimmed over the obvious, but a book or manual would be a good investment if you plan on keeping it.

I presently can only supply pics of an edelbrock performer, quadrajet, with stock linkage on a manual 84 sb. So if they will help, I'll send or post them.

Tool · 10-23-2004, 11:23 AM

I'm tryin my best, to get a pic of my linkage on the board, so somebody could see what I've got goin on. I've got my main throttle cable, I know where that goes, then I've got the two springs, I believe I know where they hook up, but THe third cable Has a end on it that I can't see where it would hook up at. I took pics of the carb, befoe I took the old one off, and for some reason I took the pics after I took these three things off, and know believe it or not I can't rember for the life of me how to hook these blasted things back up. Any help would be great help.

screwballl · 10-24-2004, 12:29 PM

when i put my Edelbrock 600cfm on my 76GM 350 the ONLY vacuum lines i kept were PCV, Brake booster and the advance for distributor.. it had the factory Qjet on it, gutless crap of a carb ive ever had.. love the new Edel

i think the third that you are talking about maybe the transmission linkage cable? usually theres a hookup on the lower end of the throttle linkage if i remember right

Tool · 10-24-2004, 11:44 PM

I was readin a haynes repair manuel, and I believe it's the transmission linkage cabel, also. I need to go take a look at it and take another stab at it. I don't mean to sound stupid, but what are the major functions of all the vacum lines. On the holley I have I believe there are only two vacum lines and I was just wonderin how that would work out. I can't wait to get this thing all hooked back up so I can bust the old girl off again.

Tool · 10-25-2004, 11:45 PM

I've got the holley all hooked up, and all it does when I fire it off is idles up real high, then dies. I checked the throttle to see if it was locked up, but it seems to work fine. (Could this be because my vacums aren't hooked up properly) The lack of fuel is begining to make me think there was nothin wrong with my q-jet, and the problem was really my fuel pump. I still don't understand what would make my engine idle up to top speed, without touching the throttle. Any help would surely be helpful. As far as putting pictures of the eddlebrock, sure I would definitely like to see how your's is hooked up.

screwballl · 10-26-2004, 09:38 PM

as my 2yr old broke my digital camera no pics but a basic description is easy enough...
standing in front of the truck looking at it, my Edelbrock has the vacuum advance to distributor coming from front left, PCV in front center and front right is capped. Brake booster is central back (not easily seen), gas line hooked up to top rear left side with throttle cable on top right side and tranny cable on center right side, springs are bottom right...
a few suggestions might be to replace the fuel filter or put a new inline one in close to the carb, this is good because the old Qjet should have one in the front compartment of it, an aftermarket carb needs an inline one...
also check your adjustment screws on the front (or maybe side) and also the idle screw isn't too far down causing it to immediately flood...
maybe a choke problem too..
just so many possiblities...

Tool · 10-26-2004, 11:44 PM

thanks for the response, I've got the pics on disk, but they're just a bit too large to post on the forum, I was wondering if I could send them to anybody"via e-mail" who might be able to help, so you can have a visual of what I've got goin on.

10-21-2004, 11:50 PM	#1
Tool Registered User Join Date: Oct 2004 Posts: 10	CArb Swap I just swapped out my old piece of junk Q-jet, with a questionable Holley, I've bolted up the adapter plate, and I've modified the linkage bracket, and I was wonderin about all the vacums, which I haven't started hookin up. Will the all hook back up, or do I need to make any mods to them. I haven't looked at them very closely, and I just didn't want any surprises. I was also wonderin about swappin the old intake manifold, with a holley street avenger, I have, and how colmplicated of a swap that would be.

10-23-2004, 03:40 AM	#3
badone07 Project 2 Resume Join Date: May 2004 Location: Jim Thorpe, PA Posts: 884	I don't presently have a holley on mine, but exactly which model Holley do you have? Also if you can't adapt, cut/weld up the stock linkage bracket, they do sell adjustable brackets. Get a set of intake gaskets. If you can set the motor to TDC, dump the coolant, remove the distributor, remove the intake and not drop or lose anything inside the lifter valley, you will be fine. Clean off the intake mating surfaces real well. A razor blade, gasket scrapper and/or a wire wheel on a drill and a can of brake cleaner will do. I don't use the china wall end gaskets. I use a punch to randomly dimple up the end rails and use rtv to seal them up, both on the block and intake. Some people use the intake gaskets dry as is. I use a little rtv around water coolant passages and permatex #2 around fuel. Bolt the intake on after rtv "skins up". Some people torque these down by sequence. I tighten then in sequence by feel, without stressing the intake. Put distributor back in close to where it was when you started. Just tight enough so you can move in either direction. Bolt on carb. Plug vacuum lines other than pcv. Put coolant back in. Start it up and set timing. Then adjust the carb. If you have an automatic, don't forget to hook up the vacuum modulator line. After it's been warmed up, go around and check the intake bolts 1 more time. Then figure out your linkage and vacuum line problems. I might have skimmed over the obvious, but a book or manual would be a good investment if you plan on keeping it. I presently can only supply pics of an edelbrock performer, quadrajet, with stock linkage on a manual 84 sb. So if they will help, I'll send or post them. __________________ John 1984 C30 Chevy Crew Cab Dually 1998 Jeep Cherokee 4x4 2004 Chevy Trailblazer 4x4 (wife's) 1970 Mustang FB fully tubed (getting 521 BBF & powerglide) 1978 Nova 2dr (going BBCaddy & S.P. th400) 1984 Monte SS (circle track car)

10-24-2004, 12:29 PM	#5
screwballl Tonawanda 454 Join Date: Mar 2004 Location: Liquid Sunshine State Posts: 2,755	when i put my Edelbrock 600cfm on my 76GM 350 the ONLY vacuum lines i kept were PCV, Brake booster and the advance for distributor.. it had the factory Qjet on it, gutless crap of a carb ive ever had.. love the new Edel i think the third that you are talking about maybe the transmission linkage cable? usually theres a hookup on the lower end of the throttle linkage if i remember right __________________ 91 Chevy Suburban Tonawanda 454 R2500 - SOLD!!! 04 Dodge Durango 5.7L Hemi 2WD, 24K miles (as of July 2011) In the past 30 years about 90% of Fords are still on the road, the other 10% made it home. -------------------

10-25-2004, 11:45 PM	#7
Tool Registered User Join Date: Oct 2004 Posts: 10	Still not workin I've got the holley all hooked up, and all it does when I fire it off is idles up real high, then dies. I checked the throttle to see if it was locked up, but it seems to work fine. (Could this be because my vacums aren't hooked up properly) The lack of fuel is begining to make me think there was nothin wrong with my q-jet, and the problem was really my fuel pump. I still don't understand what would make my engine idle up to top speed, without touching the throttle. Any help would surely be helpful. As far as putting pictures of the eddlebrock, sure I would definitely like to see how your's is hooked up.

10-26-2004, 09:38 PM	#8
screwballl Tonawanda 454 Join Date: Mar 2004 Location: Liquid Sunshine State Posts: 2,755	as my 2yr old broke my digital camera no pics but a basic description is easy enough... standing in front of the truck looking at it, my Edelbrock has the vacuum advance to distributor coming from front left, PCV in front center and front right is capped. Brake booster is central back (not easily seen), gas line hooked up to top rear left side with throttle cable on top right side and tranny cable on center right side, springs are bottom right... a few suggestions might be to replace the fuel filter or put a new inline one in close to the carb, this is good because the old Qjet should have one in the front compartment of it, an aftermarket carb needs an inline one... also check your adjustment screws on the front (or maybe side) and also the idle screw isn't too far down causing it to immediately flood... maybe a choke problem too.. just so many possiblities... __________________ 91 Chevy Suburban Tonawanda 454 R2500 - SOLD!!! 04 Dodge Durango 5.7L Hemi 2WD, 24K miles (as of July 2011) In the past 30 years about 90% of Fords are still on the road, the other 10% made it home. -------------------

10-23-2004, 02:13 AM	#2
Tool Registered User Join Date: Oct 2004 Posts: 10	If any body could send me a pic of the throttle linkage of a holley on a 77 gm stock manifold. Any help would be greatly appreciated

10-23-2004, 11:23 AM	#4
Tool Registered User Join Date: Oct 2004 Posts: 10	I'm tryin my best, to get a pic of my linkage on the board, so somebody could see what I've got goin on. I've got my main throttle cable, I know where that goes, then I've got the two springs, I believe I know where they hook up, but THe third cable Has a end on it that I can't see where it would hook up at. I took pics of the carb, befoe I took the old one off, and for some reason I took the pics after I took these three things off, and know believe it or not I can't rember for the life of me how to hook these blasted things back up. Any help would be great help.

10-24-2004, 11:44 PM	#6
Tool Registered User Join Date: Oct 2004 Posts: 10	I was readin a haynes repair manuel, and I believe it's the transmission linkage cabel, also. I need to go take a look at it and take another stab at it. I don't mean to sound stupid, but what are the major functions of all the vacum lines. On the holley I have I believe there are only two vacum lines and I was just wonderin how that would work out. I can't wait to get this thing all hooked back up so I can bust the old girl off again.

10-26-2004, 11:44 PM	#9
Tool Registered User Join Date: Oct 2004 Posts: 10	thanks for the response, I've got the pics on disk, but they're just a bit too large to post on the forum, I was wondering if I could send them to anybody"via e-mail" who might be able to help, so you can have a visual of what I've got goin on.



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