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Old 04-08-2011, 12:51 PM   #1
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Exclamation RB Holley setup, Carb and Dizzy Tuning Help

1984 12a think its street port but not sure, 465 cfm holley. header back single exhaust, upgraded coils. Where do the vaccum advances get vaccum from and do one or both need to be hooked up rb says trailing only but that sounds wrong. also how do i setup the carb correctly (tune it) and what timing should i be runing. Right now car wont ideal under 1500 and wont cold idle. Any help is greatly appreciated.
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Old 04-09-2011, 01:32 AM   #2
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Quote:
Originally Posted by TS87FC3S View Post
1984 12a think its street port but not sure, 465 cfm holley. header back single exhaust, upgraded coils. Where do the vaccum advances get vaccum from and do one or both need to be hooked up rb says trailing only but that sounds wrong. also how do i setup the carb correctly (tune it) and what timing should i be runing. Right now car wont ideal under 1500 and wont cold idle. Any help is greatly appreciated.
I dont hook up the vacuum advances, I set the timing at 5-6k RPM which is where the weights should be engaged and I'll have to get back to you on where I have them set at that RPM (my notes are in my car). As far as setting up the carb, I would first set the timing so it will idle. Once it can idle set the fuel pressure and floats. Then you can play with the Idle/Air mixture screws. I generally turn them clockwise (slowly) till you to hear the engine start to die and back them off a 1/4-1/2 turn. This should get you in the ballpark.
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Old 04-09-2011, 07:02 AM   #3
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What zach said also have a set or two of spare leading plugs you'll need em when you start tuning. Also your rb Holley should have a DVD with it(mine did anyways) that tells you how to set the floats change the jets etc. Also while tuning look at the plugs and it'll give you a idea how rich/lean your running

As for the vacuum advances I know several people that don't run them so I'd say f it haha.
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Old 04-09-2011, 09:20 AM   #4
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i set the timing at 0 degrees at idle with vaccum advance hooked to both advances and the car idle super smooth (1100 rpm cant get it any lower) and runs great whats the deal with not hooking up the advances?
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Old 04-09-2011, 11:30 AM   #5
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Alright I set my timing to 23* before top dead center on the Leading and 8* before top dead on the Trailing and at 5k RPM. I don't hook the vacuum up because I find it redundant.
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Old 04-09-2011, 06:31 PM   #6
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Check your gaskets and vacuum ports on carb sounds like a vacuum leak mine I can make it idle close to 600 rpms. Make sure the carb to intake gasket is good
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Old 04-09-2011, 10:15 PM   #7
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Quote:
Originally Posted by IH8DSM View Post
Check your gaskets and vacuum ports on carb sounds like a vacuum leak mine I can make it idle close to 600 rpms. Make sure the carb to intake gasket is good
sprayed throtlle body cleaner (extremely flammable) while running no change in rpms, so i would say gaskets are good i can change timing and have it idle lower
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Old 04-09-2011, 11:51 PM   #8
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Any improvment?
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Old 04-10-2011, 01:56 PM   #9
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Quote:
Originally Posted by FC Zach View Post
Any improvment?
havent had time to mess with it yet, i will do it tomorrow and let u know
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Old 04-14-2011, 07:09 PM   #10
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did timing the way u said fc zach car started running hot and had a horrible low end no improvement to upper end, so i set it the way racing beat says too no problems runs great, just need a regulator now fuel pressure is fluctuating alot
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Old 04-14-2011, 10:21 PM   #11
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It sounds like you used the markings on the pulley, which are used to set timing at idle. However you did it, you got it to work now.
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