Quad to holley
Burning Brakes
Joined: Jul 2006
Posts: 833
Likes: 4
From: Mexico NY
Here wego!!!
Just did this.. and am still doung this....
A: The vac t on the rear of my intake did not clear the rear fuel bowl on my holley 750, I needed to t off the line with a sinle port vac fitting..
B: Some Holley's don't provision for pvc valve
C: Your center stud to mount the air cleaner is now too long. (and WILL put a hole through your hood!!!!)
D: Your air cleaner height will be different now.
E: Your fuel lines will not match up and will need to be re-created.
F: Your vac booster line is now too short and needs to be replaced with a longer one.
G: You'll need an external filter now as your q-jet was internal...
H: You'll need a throttle cable bracket..
and the stock replacement holley / cheese-burger mrgaskit one will be too short and need hacking.. Unless you shell out some change for a good one...
I: You'll need to buy the correct stud for the holley carb to fit your throttle cable..
J: You'll need a carb stud mount kit to bult up the carb
K: you'll need a spread-bore to square bore adapter kit.
If your using a "holley direct replacement spreadbore" carb just stay with the q-jet and get her re-built,...
A: The vac t on the rear of my intake did not clear the rear fuel bowl on my holley 750, I needed to t off the line with a sinle port vac fitting..
B: Some Holley's don't provision for pvc valve
C: Your center stud to mount the air cleaner is now too long. (and WILL put a hole through your hood!!!!)
D: Your air cleaner height will be different now.
E: Your fuel lines will not match up and will need to be re-created.
F: Your vac booster line is now too short and needs to be replaced with a longer one.
G: You'll need an external filter now as your q-jet was internal...
H: You'll need a throttle cable bracket..
and the stock replacement holley / cheese-burger mrgaskit one will be too short and need hacking.. Unless you shell out some change for a good one...
I: You'll need to buy the correct stud for the holley carb to fit your throttle cable..
J: You'll need a carb stud mount kit to bult up the carb
K: you'll need a spread-bore to square bore adapter kit.
If your using a "holley direct replacement spreadbore" carb just stay with the q-jet and get her re-built,...
Racer
Joined: Nov 2007
Posts: 318
Likes: 3
From: kuwait
Just did this.. and am still doung this....
A: The vac t on the rear of my intake did not clear the rear fuel bowl on my holley 750, I needed to t off the line with a sinle port vac fitting..
B: Some Holley's don't provision for pvc valve
C: Your center stud to mount the air cleaner is now too long. (and WILL put a hole through your hood!!!!)
D: Your air cleaner height will be different now.
E: Your fuel lines will not match up and will need to be re-created.
F: Your vac booster line is now too short and needs to be replaced with a longer one.
G: You'll need an external filter now as your q-jet was internal...
H: You'll need a throttle cable bracket..
and the stock replacement holley / cheese-burger mrgaskit one will be too short and need hacking.. Unless you shell out some change for a good one...
I: You'll need to buy the correct stud for the holley carb to fit your throttle cable..
J: You'll need a carb stud mount kit to bult up the carb
K: you'll need a spread-bore to square bore adapter kit.
If your using a "holley direct replacement spreadbore" carb just stay with the q-jet and get her re-built,...
A: The vac t on the rear of my intake did not clear the rear fuel bowl on my holley 750, I needed to t off the line with a sinle port vac fitting..
B: Some Holley's don't provision for pvc valve
C: Your center stud to mount the air cleaner is now too long. (and WILL put a hole through your hood!!!!)
D: Your air cleaner height will be different now.
E: Your fuel lines will not match up and will need to be re-created.
F: Your vac booster line is now too short and needs to be replaced with a longer one.
G: You'll need an external filter now as your q-jet was internal...
H: You'll need a throttle cable bracket..
and the stock replacement holley / cheese-burger mrgaskit one will be too short and need hacking.. Unless you shell out some change for a good one...
I: You'll need to buy the correct stud for the holley carb to fit your throttle cable..
J: You'll need a carb stud mount kit to bult up the carb
K: you'll need a spread-bore to square bore adapter kit.
If your using a "holley direct replacement spreadbore" carb just stay with the q-jet and get her re-built,...
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Safety Car
Joined: Apr 2000
Posts: 3,802
Likes: 61
From: Wichita KS
Drifting
Joined: Aug 2008
Posts: 1,381
Likes: 11
It appears you are inexperienced with this sort of thing. Probably best to leave it alone. For someone who is up to the level of changing brakes, shocks, water pumps and the like, a carb swap is a piece of cake and usually takes about an hour or two depending on fuel lines and linkage. If your q-jet is giving you problems that can't be fixed, the Holley 80555C is a direct bolt on spreadbore replacement. A novice can swap ii out in about an hour. All vacuum and fuel lines match up as does the linkage. It uses a little more gas than the q-jet but gives up nothing in performance.
Melting Slicks
Joined: Mar 2006
Posts: 3,456
Likes: 102
From: Piedmont Va
St. Jude Donor '11-'12-'13,'19-'20
It appears you are inexperienced with this sort of thing. Probably best to leave it alone. For someone who is up to the level of changing brakes, shocks, water pumps and the like, a carb swap is a piece of cake and usually takes about an hour or two depending on fuel lines and linkage. If your q-jet is giving you problems that can't be fixed, the Holley 80555C is a direct bolt on spreadbore replacement. A novice can swap ii out in about an hour. All vacuum and fuel lines match up as does the linkage. It uses a little more gas than the q-jet but gives up nothing in performance.
I swapped to this carb last year and it fits and runs great I was even able to use the factory cowl air cleaner( but had to remove the seal). I did have to cut the stud shorter. 
Thread Starter
Instructor
Joined: Oct 2008
Posts: 178
Likes: 1
From: windsor ontario
Ok so I got a holley 670 street avenger and like you TIMGMAN I have the problem with the t fitting so I guess that ihave to get a fitting that is a90 ant threads in then shoots off in a single line and when I have the clearance I then put a T in... is this correct.
Since i have a performer intake do I need the square bore adaptor?
Since i have a performer intake do I need the square bore adaptor?
Le Mans Master
Joined: Mar 2008
Posts: 5,948
Likes: 72
From: Oxford MA-----You just lost the game!!!!
Ok so I got a holley 670 street avenger and like you TIMGMAN I have the problem with the t fitting so I guess that ihave to get a fitting that is a90 ant threads in then shoots off in a single line and when I have the clearance I then put a T in... is this correct.
Since i have a performer intake do I need the square bore adaptor?
Since i have a performer intake do I need the square bore adaptor?
That depends on wether your intake manifold is spreadbore or squarebore, Performers come both ways.
IMHO, nobody needs a squarebore adapter, what they need is a manifold that matches their carb. Or vice-versa.
Pro
Joined: Jul 2008
Posts: 699
Likes: 3
From: Millersville, MD
Pro
Joined: Jul 2008
Posts: 699
Likes: 3
From: Millersville, MD
It appears you are inexperienced with this sort of thing. Probably best to leave it alone. For someone who is up to the level of changing brakes, shocks, water pumps and the like, a carb swap is a piece of cake and usually takes about an hour or two depending on fuel lines and linkage. If your q-jet is giving you problems that can't be fixed, the Holley 80555C is a direct bolt on spreadbore replacement. A novice can swap ii out in about an hour. All vacuum and fuel lines match up as does the linkage. It uses a little more gas than the q-jet but gives up nothing in performance.