To much GAS

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AJ/FormS said:
Aw, give the guy a break. It hasnt even been 24 hours yet.
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Yea, if he is trying to start something he is right at the cusp. There are better intakes than cross rams anyway.

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its pretty clear that its fuel issue, or you just don't have near the spark to burn all that fuel .

it sounds to me like you have a carb flooding or you have way too much fuel pressure.

I have a dual quad using two edelbrock 600's and im not having any issues what so ever , maybe a touch on the rich side , but definitely not fouling plugs.

this post pretty much covered it already

AJ/FormS said:
There are just so many things it could be. Where to start?
I guess a good a place as any, is to see what the boosters are doing,while the engine is idling. They should be dry.
Perhaps the idle speed has been run up, to compensate for late ig.timing,leaking floatvalves.leaking power valves, or too much fuel pressure.
Yeah I think those boosters will tell you something.
Some manifolds suffer from puddling. Sometimes through temperature problems. Sometimes through less than optimum design.
Perhaps your valve lash is on the tight side, or gets to be on the tight side after warming up.Big cams can send a compression pressure spike back up through an open intake valve.(Well they all do it to some extent). Well this spike, if it finds its way past the booster, can signal the carb to dump a bit of fuel. If all 8 cylinders do it, this can be a problem.
I have never had a hemi, nor tuned one. But I seem to remember those cross-rams having tuning issues,back in the day.
You need to dry up that intake, I think.And checking the boosters is where Id start.Well actually the float level is where Id start. Or maybe boosters first then float level. Naw just check the boosters first. If theyre dry,the float level will be at least close.
How about cluing us in as to timing numbers? Idle speed? Idle vacuum?Single plug heads? Timing controls? Velocity stacks?Engine temp?
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I will concede the cool factor, the look is great. The cool factor and the torque numbers aren't gonna solve this. I think the answer is in this thread already, but I would like to know the answer for certain. So many of these threads die with no resolutions posted.
 
That is the first thing you should do is tell us what you have checked and is OK. Like fuel pressure if running a electric pump, float level, power valve ( number and if it is good) how much vacuum at idle, jetting, ignition timing etc etc etc. With this kind of info we could give you a better idea where you should be looking.
 
Do you know how to tune a Holley or any carb? You need some tools to help do so or you're pretty much wasting time..

Before doing any tuning I would seriously consider a fuel pressure regulator with a pressure gauge after the reg, but before he carb - Holley's don't need more than 7psi and if it's getting more it could be over filling the bowls and dumping fuel out the boosters (been there)- could also reset the floats as well - there is a Holley video on youtube on how to redo that..

Timing light
Screw drivers for setting idle mixture, idle speed
Vacuum gauge
Carb jet assortment
Pump cam, and squirter assortment (Holley)
Extra bowl/metering plate gaskets
Secondary plates to adjust secondary jetting (4160 style carbs)
extra carb base gaskets - I reuse them twice and toss them.. had my carb off MANY times
Cheat and splurge on a AEM wide band A/F gauge kit (I tuned a single Holley in 2 hours in my driveway with a couple blasts up and down my road But I had dumped $120 or so into extra parts for tuning.. plus $200 for the wide band)

Be sure the vacuum advance if it has one is hooked to ported vacuum and not manifold vacuum

Tune the primary carb first (usually the front one on dual carb set ups) - document what the setup is at right now so you have a base to go off of - wright down the jetting and the plate

base tune is -

Set timing to stock (10-12* BTDC or so OR 32-34*@ 2,000-2,500rpm total if you do it that way)

Set idle speed as low as possible (750-800)

Hook vacuum gauge up to manifold vacuum source - all idle mixture screws 1.5 turns from seated (gently seat the screw and turn out 1.5 turns) try to get the highest reading you can turning both screws the same amount (I go 1/8 -1/4 turn at a time in either direction but some say go a 1/2 at a time) - turning out adds fuel turning in takes fuel out..

Tune from there.. I strongly suggest getting the wide band for a DIY'er you don't need to mount it in the car - I didn't just made a harness with a on/off switch and had a passenger hold the gauge and watched what it did - also do not spin the tires while driving it as it will hide flaws in the tune.. do not stomp the gas either easy into it so you can feel/see a hicup in the tune
 
One Carb is bad. Tear em both down comparing one against the other. Especially the gaskets. Don't keep running it like it is unless you want to rebuild it.
 
I had both carbs rebuilt again and they found the base plates were worped and I had a bad float. Thanks for all that helped, you guys are great.
 
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