Rich or lean that is the question

Old 04-28-2010, 06:57 PM
  #1  
rabbit
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Default Rich or lean that is the question

I got a new car about 2 months ago and it it just starting to get cruising weather(yes a street car). I haven't pulled the plugs yet to try reading them but I was wondering. My car is running rich I think. It runs awesome at full throttle but at idle and cruise it has an awful hesitation, very little low throttle response and it burns your eyes something fierce just to walk behind it. Am I right in thinking rich could this be a very lean condition?
Thanks, Rabbit

I forgot to mention this is a 427 BBC with old school 3 pc Weiand tunnel ram and 2 450 cfm holley carbs.
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Old 04-28-2010, 11:18 PM
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Tod74
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Default Re: Rich or lean that is the question

Originally Posted by rabbit
I got a new car about 2 months ago and it it just starting to get cruising weather(yes a street car). I haven't pulled the plugs yet to try reading them but I was wondering. My car is running rich I think. It runs awesome at full throttle but at idle and cruise it has an awful hesitation, very little low throttle response and it burns your eyes something fierce just to walk behind it. Am I right in thinking rich could this be a very lean condition?
Thanks, Rabbit

I forgot to mention this is a 427 BBC with old school 3 pc Weiand tunnel ram and 2 450 cfm holley carbs.
If it burns your eyes it's rich. The tunnel ram needs to go. Probably doesn't have enough air velocity at part throtle low rpm.

JMO
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Old 04-29-2010, 07:42 AM
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X2
Dave
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Old 04-29-2010, 09:29 AM
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TheYellaBrick
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Probably LEAN as them carbs at such HIGH altitude !!

I'm getting a nose bleed from just LOOKING at his car !!! :shock: :shock: :shock:

LOVE IT !!!

Check it out gang !!

http://www.racingjunk.com/profile/40325
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Old 04-29-2010, 09:53 AM
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Scooterz
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Amen Double/D!!! Yep, very cool. I have agree w/ Tod on that one. It is rich on the low end/idle circuit... not enough vacuum it is dumping too much fuel.
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Old 04-29-2010, 10:38 PM
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cepx111
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IMO< U need 2 things less fuel at an idle and more at part throttle, for the idle circuit, adjust the mixture screws IN till it falls off then back out a 1/4 to a 1/2 turn out, also check float level, if their too high it will make it idle rich too.

With a tunnel ram you dont exactly have alot of signal strength from the motor, so you need to dump a ton fuel in the accelerator pump circuit to over come the sudden rush of air when you open the throttle, I recommend 50cc accelerator pumps on the primaries as I starting point.
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Old 04-30-2010, 06:42 AM
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Over the years I've seen very drivable tunnels on the street and a lot which were totally undrivable. It all depends on the complete engine combination.
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Old 04-30-2010, 11:09 AM
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rabbit
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Originally Posted by cepx111
IMO< U need 2 things less fuel at an idle and more at part throttle, for the idle circuit, adjust the mixture screws IN till it falls off then back out a 1/4 to a 1/2 turn out, also check float level, if their too high it will make it idle rich too.

With a tunnel ram you dont exactly have alot of signal strength from the motor, so you need to dump a ton fuel in the accelerator pump circuit to over come the sudden rush of air when you open the throttle, I recommend 50cc accelerator pumps on the primaries as I starting point.
Thanks that is the kind of answers I was looking for. Floats are good just running "fat" down low. I will look at the idle mixtures and then start in with squirters and pumps. I have always sucked at tuning carbs but the looks of the tunnel ram just screams "don't even think about it!".

By the way guys the little Chevy II you talked about is no longer mine, I have a new toy I am working on now.

Thanks everyone, Scott
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