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  #1  
Old 04-28-2001, 09:44 PM
scootertrs scootertrs is offline
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Question

Hi

I have a series of problems w/my 440 69 6 pack manual shift superbee which am hoping someone can help me overcome. I bought new carbs to replace the 4 barrel (motor originally 6 pack and rebuilt using 6 pack specs, only mods being port matching, port polishing, comp. valve job), and now it will not run worth a $#@%$. The simptoms are as follows:

During WOT from a dead stop or from a slow in motion start, the rpms begin to pick up, vac secondaries begin to open, and then the stumbles begin. It sounds as if it has a stomach disorder until it clears up, vac secondaries then completly open and and then it takes off like a bat out of hades.

Twice, from a dead stop, I had a very impressive fireball exit the carburator.

No black smoke, no other simptom. Idles just fine (well w/ a lope :-))

The vac secondary springs are the yellow ones. The carbs are the new P4349236 outers and the new P4349235 inner. I understand that these carbs are 50 state legal, which may be part of the problem. How do I modify them to work?

Ignition is stock orange box retrofit. With vac. disconnected. I am only getting about 18 degrees total mechanical advance, so I must set my initial timing at 20 deg. to get full 38 deg at about 3000 rpm. Is something wrong w/my distributor?

Any ideas? suggestions, I want it to go as good as it looks!!

thanks
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  #2  
Old 04-28-2001, 10:26 PM
6pakman 6pakman is offline
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well theres the problem, those carbs are only 50 state legal, florida being the 51 state there not legal there. thats why they wont run right. just kidding. what you have is very tipical of the 6 pack unit. thay will bog if you mash the pedal at a stand still. iv had alot of six packs and i could never get them to adjust right. try advaccing the timing a bit . its touch and go. good luck.
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Old 04-28-2001, 10:34 PM
6pakman 6pakman is offline
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by the way , what the hell is a bat outta hades?
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Old 04-28-2001, 11:55 PM
scootertrs scootertrs is offline
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by the way , what the hell is a bat outta hades?

Its from an old TV commercial where a old man, as the passenger yells at the driver who is an old woman, driving a car that is just creeping along painfully slow, barely moving, to "slow down... you are driving like a bat out of hades"... Guess you had to see it, but I could not help but bust a gut whenever it came on.

As far as the 50 state thing, what I meant is that it meets California emmission stds, and California being so "special" environmentally, sometimes requires cars to be so lean.

Ideally, I would like to know if you have a 440 six pack that runs well, what is its set up... jet sizes, power valve size, metering plates, and vaccumm secondary spring color. I would also like to know what your initial advance and total advance is set for.

thanks
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Old 04-29-2001, 12:19 PM
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charger_dan charger_dan is offline
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Default check the pump

Hey,
The "fireball out of the carb" brings to mind a couple of questions:

1. Have you checked your center carb accelerator pump for proper adjustment?
2. Have you experimented with different initial timing settings, to see if that positively or negatively effects throttle/performance transition?
3. Are float levels / idle mixture adjusted properly?

Typically, on an otherwise healthy mill, a backfire means one thing: you're lean, baby.
You didn't provide cam / timing curve / car specs, but it sounds like you're outside of the "stock calibration" operating range of the carbs. Get yourself a book on tuning Holley carbs.

Richard Ehrenberg ( mrmopar@computer.net ) of Mopar Action magazine is a great guy to e-mail for this kind of advice. You can believe what he says.
The six pack setup is a great system - and a great opportunity to learn carb tuning / tweaking.
You think it runs hard now... wait 'til its tuned correctly!
Good luck!
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Old 04-29-2001, 12:50 PM
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ehostler ehostler is offline
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Either the accelerator pump is out of adjustment, or the secondaries are opening too soon. Most likely and adjustment on the accelerator pump.
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  #7  
Old 04-29-2001, 01:48 PM
rat roaster rat roaster is offline
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Ok the thing runs good if you dont hammer it a low rpm right? The timming is fine at 36 deg (38 may be a bit much but if it likes it great) as long as the mark on the dampner is ok with TDC. Unhook the secondaries(the arms from the vacume pods to the carb( A little C clip) and hammer it under load (while driving) if it runs good the middle carb works fine,which I suspect it will. I feel that the outboard carbs are opening too fast ,try a stiffer spring. Also did these vacume pods on the outboards come with a ball bearing intalled in the vacume port in by the diaphram. First check all the float levels ,then make sure the linkage is set up properly ,change springs if necessary. The ball bearing is used to slow down the speed that the carbs open by partially plugging the vacume hole,alot of 3310 holley 4 barrells come with them. To see if there is ball bearings you have to remove the vacume pods and look in the top where the diaphram (4 LITTLE SCREWS) installs into the pod , there will be the vacume port that pulls on the diaphram and maybe a little crome ball bearing, if its there leave it there and try a different spring. If you find that the carbs are opening to slow then you can take the ball out . I have mucked with these carbs quite abit ,I ran them on a stock 6 pack manifold and on a STR-14-6 with a good sized cam with about 4.5 inches of vacume at idle in gear. On the STR with the big plenum area at low rpm you had to whatch the opening speed or the engine would do like you said pop and garble and then take off like ,Well You Know. I have some old books on these mods if you want I can fax or E-mail you some stuff. The six pack system is not a perfect system and some people cant wait for the secodairies to open and they try to speed things up but the secondairies (in stock form) have no accelerator pumps so they have to open slow ,remember you are opening up a couple of 500 cfm carbs. If you really want to have fun phone 6 PACK SPECIALTIES and order two out board carbs with accelerator pumps and manual linkage and install a 3000 rpm converter or bigger and YAH-HOO. Gas milage will really suck though as now its a progressive system.

Rex
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Old 04-29-2001, 04:46 PM
scootertrs scootertrs is offline
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OK guys... Thanks for the info... I am now glad to report she is one quick puppy!!

First, I checked the TDC and the mark on the crankshaft balancer was OK... No problem there.

Then set the timing at 38 degrees max all in (both vac and mechanical)

Adjusted the center carb pump shot according to specs (was way off originally)

went two spring levels higher (from yellow to plain ) on the vacumm secondary cannisters

and YOUZA!!!!!!! AIEEEEE!!!!!! etc. etc.

thanks again guys
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