351W stalls at traffic lights

Jaha95

Member
Apr 26, 2020
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Vejle > Danmark
Hi guys!

Ive got a 69 351w with FMX tranny and every time i take og for a drive og Will stall on me.
I can stop at a traffic light and after 5-10 seconds the rpm will drop from 700 to 250 and then stall.
If im quickly i han put in Neutral and keep it Running.
Ive also noticed that when i go from park to Drive, the car tries to jump forward

Can it be my converter in the way out?

Current things checked:
Oil level on the transmission
Aluminium radiator mounted (the coolant temp was a bit too high for me)
Rebuild carburator
New fuel pump
Checked timing and set to 10 degrees
New plugs gapped to 0.030

Oh and the current setup
0.30 over bore
Ported heads
Edelbrock 600cfm carb
Edelbrock rpm intake
Pertronix flame Thrower coil
Pertronix ignitor 3
Lunati barebones 280/290
Holley high flow mechanical fuel pump
Hooker headers
 
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DBegley

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Jun 24, 2017
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My 68 302 does that especially when it first gets started up. I think its a carb issue. My car is a 4 speed so I can control the idle with the clutch in. I put a new Holley carb in last summer. Been tweaking the settings but would like someone that knows carbs better than me check it.
 

7991LXnSHO

Now I want a 10 year badge
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Sep 1, 2010
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I do not know the carb make and model, so this will be general advice. The idle circuit might be partially clogged, and the idle mixture screws could need adjusted. After those issues are addressed, the idle speed screw should need adjusted.
 
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2Blue2

will be trying this sex one when I can find it
Mar 5, 2019
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The idle circuit might be partially clogged, and the idle mixture screws could need adjusted
yes that is most likely
and or dirty fuel filter. Old car with old tank and lines? Tank not venting properly. Vac leak.


Edelbrock 600cfm carb
This carb not as picky as a holley when it comes to dirt but still can happen.
 

7991LXnSHO

Now I want a 10 year badge
10 Year Member
Sep 1, 2010
2,991
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Kearney, NE
I skipped that line about the carb. Yes, vacuum leaks are also a common cause of idle issues. Check the base gasket and any caps, too. Does this transmission have a vacuum line to a regulator?
 

Jaha95

Member
Apr 26, 2020
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2
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Vejle > Danmark
I do not know the carb make and model, so this will be general advice. The idle circuit might be partially clogged, and the idle mixture screws could need adjusted. After those issues are addressed, the idle speed screw should need adjusted.
Its an edelbrock 1405 600cfm
Ive already har the carb apart for a rebuild, so i dont Think the carb is clogged

Ive tried setting the idle screws to 2,5 turns out and adjusting in for the maximum vacuum and ends at about 2 turns.
Am i Going too lean?

yes that is most likely
and or dirty fuel filter. Old car with old tank and lines? Tank not venting properly. Vac leak.



This carb not as picky as a holley when it comes to dirt but still can happen.
Fuel filter has been changed, same goes for the lines, so i dont believe that fault is there

Ive just tried a vacuum meter on the inlet of the carb to check the vacuum, im Running About 14 Hg, when in drive, is it too low?

I skipped that line about the carb. Yes, vacuum leaks are also a common cause of idle issues. Check the base gasket and any caps, too. Does this transmission have a vacuum line to a regulator?
Ive just tried to change intake + carb gasket and no change

When you sat Line to regulator?
I have a Line Running from a T-piece in the intake to the tranny?

Ill try to have Another look after a vacuum leak
 
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