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General Site Info => General Discussion => Topic started by: Buddy on November 05, 2010, 06:47:53 pm

Title: from a holley to a quadrajet
Post by: Buddy on November 05, 2010, 06:47:53 pm
I just took of my holley carb because it was working like garbage, Now I am trying to install my quadajet. The problem is the part where the throttle cable is seems different. I cant seem to understand how the bracket secures to the carb. I understaand the cable part just not the part where the bracket holds the cable back off the carb. It is a brass color and both cables pass through it. Also i have no clue where the vacum lines go, it seems to have a different set up.can some one explain this part. I only have 3 lines on my holley one to the booster and one to the vacum and on to my PCV. but  dont which one they are on the quadrajet one. Also there are no bolts that came witht this carb any idea on the length and size of the two rear bolts? I am starting to think this might have been a bad idea, but i really want to go with this carb as I just paid to have it rebuilt.
Title: Re: from a holley to a quadrajet
Post by: Buddy on November 06, 2010, 06:59:24 am
anybody..... i am reallylost on this one!!
Title: Re: from a holley to a quadrajet
Post by: 1980c10 on November 06, 2010, 07:16:24 am
any pics?
Title: Re: from a holley to a quadrajet
Post by: eventhorizon66 on November 06, 2010, 09:19:15 am
Factory Q-jets never used a throttle bracket that bolted at the rear left corner of the carb base like what you're most likely describing (pic?).  The factory throttle brackets bolted to the rear left two intake manifold bolts.  Here is an adjustable aftermarket version of the factory bracket: http://www.summitracing.com/parts/EDL-8031/

The Q-jet PCV vacuum line goes to the 3/8" barb on the front of the carb base (under the fuel filter housing).  The brake vacuum line would normally go to the back.  There is a NPT threaded hole back there (center of baseplate) that you can screw a factory fitting into or just a NPT to 3/8" barb fitting you can find at any hardware store.
Title: Re: from a holley to a quadrajet
Post by: Buddy on November 06, 2010, 01:41:35 pm
Ok thanks alot, one last question? what do i do with the lines i dont have something to go to them? just leave them open or block them off somehow
Title: Re: from a holley to a quadrajet
Post by: eventhorizon66 on November 06, 2010, 04:10:52 pm
Never leave vacuum ports open.  Cap them off with some appropriate rubber vacuum caps.

You can find these at any auto parts store:
http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_x_9110159-P_x_x?cm_mmc=CSE-_-Google-_-VALUE3-_-VALUE4&ci_src=14110944&ci_sku=9110159
Title: Re: from a holley to a quadrajet
Post by: 4x4orbust on November 06, 2010, 05:21:47 pm
i would not suggest using those dorman vacuum caps.    I had a huge problem with them deteriorating and allowing vacuum leaks.   there is another vinyl type caps that hold up much better.
Title: Re: from a holley to a quadrajet
Post by: eventhorizon66 on November 06, 2010, 06:40:18 pm
I've used them for years and have yet to see one deteriorate.  I'm not necessarily advocating Dorman above others, but the point is to use some sort of cap on the ports.