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#1 matty86

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Posted 17 June 2009 - 01:18 AM

heys whats up just wanted to know if anyone had an opinion on what size carb would be best with my set up. i have a 350ci 2.02heads and a choppy cam. the guy that had the motor before me had a holly 750 on it before i bought the motor from him. when i put it in my car with a different holly 750 it runs really rich no matter how i adjust it. i've been doing a lot of reading on carbs and found on a corvette site that a 600 cfm carb allow less gas and air in my engine therefore not choking it out. i have a holly 600 but i have to get it rebuilt so i just wanted to know if anyone had similair problems or opinions. thanks.

#2 9T8W66

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Posted 17 June 2009 - 01:34 AM

Unless your buzzing the engine to above 7000 rpm a 600-650 cfm Carb should be good.

If you're useing a vaccumn secondary carb try looking into a heavier spring for the secondary diaphram. This slows the secondaries opening rate and will help eliminate fuel from being dumped in. It also help the engine build more torque.

Edited by 9T8W66, 17 June 2009 - 01:36 AM.

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#3 Tyler

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Posted 17 June 2009 - 03:06 AM

There may be something wrong with the previous 750 to. Or it's jetted to rich.
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#4 matty86

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Posted 19 June 2009 - 02:01 AM

yeah i've been told that i might need to jet the 750 down but i don't really see the need for all that carb. i mean if i can use the 600 than it should save me some gas and run just as good....do they make kits that have the different springs for the vacumm secondary diaphram?

#5 Tyler

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Posted 19 June 2009 - 12:04 PM

Holley sells every piece so you can tune their carbs.
Tyler
97 Formula-6M,1.6RR,52mmTB,SLP dual cat headers,CAI,Mac cat-back,LCA's,PHR,& Nitto DR'S & 3:73 gears.Also port matched heads & intake. Best run so far-13.484 @ 102.784 mph. No run yet since cam installed.


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