New Carb
Thread Starter
Intermediate
Joined: Mar 2010
Posts: 48
Likes: 0
From: Coopersburg PA
New Carb
My buddy has a rebuilt Holley 600cfm that he is willing to part with and put on my L48 '74. Our main question is... is it going to a direct fit, or do we need to put new jets in or anything.
Team Owner
Joined: Aug 2000
Posts: 21,453
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From: Massillon,Ohio USA
2020 C3 of the Year Finalist - Unmodified
Cruise-In VI Veteran
St. Jude Donor '08-'09-'10-'11-'12
...you'll probably have to alter your fuel line set-up and I doubt your stock air cleaner assembly will work with that carburetor if you still use that. You may also have to get a special adapter plate as a stock Q-Jet is of a spread bore design and the Holley 600 is not.
Advanced
Joined: Apr 2010
Posts: 97
Likes: 9
From: Ellicott City MD
..... if you go with the holley, you are either going to need a new manifold or adapter. However with the adapter you may need to get a drop base air clearer. as im pretty sure the stock will not fit. and you will have to change or adapt your fuel line.
Melting Slicks
Joined: Mar 2007
Posts: 2,100
Likes: 12
From: Frederick Maryland
Yes, that Holley is most likely a square bore design and you have a spread bore intake. You'll need an adapter or a new intake. Along with that, as already said, a new fuel line from the fuel pump plus a different fuel filter arrangement and either all new linkages or modifications to the stock linkage.
You may well need to have the carburetor re-jetted as you don't know how well it's currently set up and could be a mismatch to your cam, etc. You might be lucky and not need that but you won't know that until it's installed and adjusted.
You may well need to have the carburetor re-jetted as you don't know how well it's currently set up and could be a mismatch to your cam, etc. You might be lucky and not need that but you won't know that until it's installed and adjusted.
