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390 CFM carb starving on uphill?

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Thikstik View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Thikstik Quote  Post ReplyReply Direct Link To This Post Posted: Aug/13/2018 at 8:04pm
also check for loose base nuts , metering plate bolts
75 gremlin x, jeep 4.0 headed 258,
264H Cliff cam, intake,header. 390 holley. I want a 282 VAM motor!

AC/PS/PDB.

72 AMX , 304 2bbl, 3speed, now disks...probably will sell, want an automatic /AC.

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REBEL_BOB View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote REBEL_BOB Quote  Post ReplyReply Direct Link To This Post Posted: Dec/16/2018 at 7:41am
I ran holley carbs in the early 70s and found the float level critical and the bowl vents had to be extended so fuel would not splash down the throttle and cause a stumble when climbing hills    good luck
THANKS FROM REBEL_BOB
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Thikstik View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Thikstik Quote  Post ReplyReply Direct Link To This Post Posted: Dec/17/2018 at 11:20am
Any luck?  Did you give up on it?  
75 gremlin x, jeep 4.0 headed 258,
264H Cliff cam, intake,header. 390 holley. I want a 282 VAM motor!

AC/PS/PDB.

72 AMX , 304 2bbl, 3speed, now disks...probably will sell, want an automatic /AC.

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tomj View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote tomj Quote  Post ReplyReply Direct Link To This Post Posted: Dec/18/2018 at 12:09am
the main jets are low in the bowl; the fuel level (float level) would have to be crazy low to uncover them on a hill. possible but I think unlikely.

"up a hill" means foot in the throttle which means lower vacuum which means vacuum advance drops. if you set base spark timing (distributor position) with the vacuum hose on, it would exactly create your symptom. as soon as you press the throttle under load, vacuum advance will drop (might even go positive) and you'd get a huge bog.

 a simple trick for setting/checking spark timing is to simply pull the vacuum hose off the distributor and plug it. then set spark timing and drive it around. vacuum advance is only/mainly for improved light-throttle light load cruise mileage. you will do no harm without vacuum advance, and it will make all the interactions with load and vacuum disappear.


1960 Rambler Super two-door wagon, OHV auto
1961 Roadster American, 195.6 OHV, T5
http://www.ramblerLore.com

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