Author Topic: Need advice on 7028213 carb  (Read 3817 times)

Offline Mr.Pontiac

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Need advice on 7028213 carb
« on: September 10, 2009, 08:01:29 PM »
on a 68 corvette, 427 motor with 525 lift crower cam stock gears,base plate has .080 holes for air and fuel metering, should i go to at least .098?? No idle circuit working at all no visible improvmant with idle screws at all. Idle speed screw adj. all the way in until binding spring, car idling at 850 rpm.Secondly, should i open pull over enrich. tubes to .036??Lastly to improve or get some adj. should i open up upper air bleeds to .068? Needle and seat .101 going to open up to .135 to .140 to get some fuel into the carb. ok??? rbudney@comcast.net Secondary rods are AN BIG!!HELP!!

Offline Cliff Ruggles

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Re: Need advice on 7028213 carb
« Reply #1 on: September 11, 2009, 04:08:19 AM »
What are the rest of the cam specs?

What is the static compression ratio?

What are the sizes of all the items listed in the high performance chapter?

Lower idle airbleed:
Upper idle airbleed (airhorn or main body):
Idle tube:
Idle down channel:
Idle bypass air:
Lower main airbleed:
Upper main airbleeds:
Main jets:
Primary metering rods (number and letter):


Offline Mr.Pontiac

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Re: Need advice on 7028213 carb
« Reply #2 on: September 11, 2009, 01:03:10 PM »
Cliff,Lower air bleed .063
one jet .072 one .073
46B METERING RODS
SECONDARY HANGER k AN RODS
Idle tubes removed .038
secondary tube restict. .028
Main air bleed, air horn .046
air bleed body .046
needle seat .101
Not my car going on specs i saw 525 lift on Crower cam  hyrdraulic10.5 compression this is just a bare frame off 68 vette restored

Offline Mr.Pontiac

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Re: Need advice on 7028213 carb
« Reply #3 on: September 12, 2009, 07:58:50 AM »
Base plate , air and fuel adj. screws  holes are only .080 should i open them up to at least .100

Offline Mr.Pontiac

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Re: Need advice on 7028213 carb
« Reply #4 on: October 02, 2009, 02:54:36 PM »
Shame , got no more replys on the carb. here????

Offline Cliff Ruggles

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Re: Need advice on 7028213 carb
« Reply #5 on: October 04, 2009, 04:58:21 AM »
We talked about the specifics by phone, never heard any more about the upgrades or if it was working any better?....Cliff

Offline Mr.Pontiac

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Re: Need advice on 7028213 carb
« Reply #6 on: October 05, 2009, 04:37:05 PM »
I can understand the frustration you must fill sometimes, i called you got what info i needed and helped on his carb. gentleman go,s and orders one from jet performance???What can i say???He will compare both or so he says??? Only getting 10 inches vacum max at idle with the jet carb.Timing is set at 12 tdc minute he advances it motor dies??I made a suggestion that i thought he put cam in wrong position?? Any ideas would be helpfull, please

Offline Cliff Ruggles

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Re: Need advice on 7028213 carb
« Reply #7 on: October 06, 2009, 04:35:00 AM »
Those things happen, simply troubleshooting by buying parts.  A correct calibrated original carb would be better than any "generic" unit purchased. 

I just spent quite a bit of time trying to help out a customer, and it turns out the Accel distributor he had purchased was defective.  He installed a new MSD read to run unit, and the problems went away.....Cliff