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 Carb recommendation 
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Joined: Tue Nov 12, 2013 2:17 pm
Posts: 10
This has been a great back and forth for me, as I'm one of those who wants to know why, instead of just do.

Mattax, Tuner, Mark, thanks for schooling me. I appreciate the positive position you're all taking with the QJ and, believe me, if I had a way to make it work without extra plumbing under the hood I would (is there a market for a true 5 to 6 PSI stock mechanical pump?) Point taken about reasonable fuel pressure regardless of what carb is installed but that's been the point all along; what is reasonable FP to a Holley is unreasonable to a QJ. I'm trying to maintain a stock appearance as much as possible, and intend to run factory hard lines from the pump to the carb. I don't want, or need, braided this or AN- that (same reason I don't care about billet bits on QFT's SS series).

Thanks very much,

Dan


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Sun Dec 01, 2013 11:47 am
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Joined: Fri Feb 08, 2013 2:37 pm
Posts: 1701
The spring in the fuel pump makes the pressure. Change the spring.

To eliminate the overpressure from a hot soak drill a .035” bleed between the high and low pressure sections. It doesn’t really need to be as big as .035”, there just needs to be a tiny leak so the hot fuel pressure can’t be trapped between the pump and the carb and overpressure the carb.

They (politicians and bureaucrats in D.C.) are mumbling about eliminating ethanol from the fuel so maybe the high vapor pressure won’t be a problem much longer. We can dream. The corn lobby won’t go down easy but ethanol is killing people (compromised fuel systems = car fires) and causing economic harm, two good reasons to eliminate it from gasoline.


Sun Dec 01, 2013 2:42 pm
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Joined: Tue Nov 12, 2013 2:17 pm
Posts: 10
Interesting thought.

However, the "correct" stock pump is a non-rebuildable unit, though I could certainly replace it with a rebuildable pump. Replacing the spring - I've never seen anyone offering a lower pressure spring, and have never read about anyone replacing the spring to lower the pressure.


Mon Dec 02, 2013 10:57 am
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Joined: Wed Feb 13, 2013 4:04 pm
Posts: 63
Quote:
I'm one of those who wants to know why, instead of just do.


I guess thats why most of us are here!

Hysteric


Wed Jan 01, 2014 7:56 pm
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