breaking up under a load
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From: Boynton Beach Florida
breaking up under a load
I installed a new fuel pump,fuel pressure regulator set at 5.5 psi a new edelbrock 600 cfm carb and filter . the problem is when it down shifts into passing gear with my foot on it, it feels like it is starving for gas. I don't think its an ignition problem because the tach isn't bouncing around..Its an 81 with all the emission junk taken off and no cat,
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From: Southeast
Originally Posted by palazzopl
I installed a new fuel pump,fuel pressure regulator set at 5.5 psi a new edelbrock 600 cfm carb and filter . the problem is when it down shifts into passing gear with my foot on it, it feels like it is starving for gas. I don't think its an ignition problem because the tach isn't bouncing around..Its an 81 with all the emission junk taken off and no cat,
Safety Car
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From: Jersey Shore Exit 98
I think the problem is the size of the carb the edelbrock 600 is a good carb but 600 cfm is too small for performance driving. around town and hwy its OK but put a load on it, drive the car hard & 600 cfm doesn't cut it. Most C1 & C2 run find w/a 650cfm but the C3's came w/a 750cfm Q-jet from the factory and you just down graded to a 600. I know this because I did the same thing & when I redo my motor the edel 600 is going up for sale & a q-jet 750 is going back on.
Last edited by Jims79; Mar 29, 2006 at 05:25 PM.
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From: Southeast
Originally Posted by palazzopl
timing is set a 12 btdc and it has a HEI distributer with a vacuum advance
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From: Southeast
Originally Posted by Jims79
I think the problem is carb the eldebrock is a good carb but 600 cfm is too small for performance driving. around town and hwy it OK but put a load on it drive the car hard & 600 cfm doesn't cut it. Most C1 & C2 run find w/a 650cfm but the C3's came w/a 750cfm Q-jet from the factory and you just down graded to a 600. I know this because I did the same thing & when I redo my motor the elde 600 is going up for sale.
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From: Jersey Shore Exit 98
Originally Posted by Fubba
When I desktop dynoed my car, upgrading to a larger carb did not give me any more power. Now that it's tuned well, it runs great
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From: Boynton Beach Florida
I had a old 600 edelbrock on before and I didn't have these problems..any ideas on what plugs to use ,,it has a mild cam and headers so I don't think the stock plugs are hot enough..
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Pro
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From: Southeast
Originally Posted by Jims79
I don't know about more hp but top end is what I think the smaller cfm carb is lacking. Like I said my car runs great around town & hwy and I'm happy w/the 600 edle but when I put a load on it she feels like can't get enough gas.
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Did you check your float bowl levels? If you're starving for fuel under high RPM's that could be the problem. Just a thought.
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From: Boynton Beach Florida
took it for a ride today . it had a slight hesitation when it was cold then it ran fine after it warmed up. I pounced on it a few times and it didn't bog down or break up..its starting to drive me nuts. going to try it later when it gets warmer this afternoon..its suposed to be in the 80's ..I did notice that the fuel filter gets very hot, its mounted above the valve cover about 6 inches before the carb.
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From: Madison Ms
Originally Posted by palazzopl
I had a old 600 edelbrock on before and I didn't have these problems..any ideas on what plugs to use ,,it has a mild cam and headers so I don't think the stock plugs are hot enough..
You check a plug yet? You may just merely need to rejet and rerod. It's very simple to do on the EB carbs. Pull a couple of plugs.......that will tell the story!! Than you will know which direction to go.
Check what jets and rods your old carb had, and compare it to the new carb. New EB's are shipped in the middle......which from my experience is way to much for a stock motor.
