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Discussion Starter #1
i apologize for being all over the forum on this issue. just trying to get some answers.

351W California Cougar. modified the tank vapor system a bit, and not too well i might add. with a full tank going uphill it appears my "vent" is covered by fuel and the car loses power.

it's fine under load and level, except under high speed and demand above 75mph. is the tank not getting enough air in as the fuel leaves at a higher rate of flow, or is the fuel pump unable to keep up?

or maybe something else? any ideas?

billy
 

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if you plugged the closed system will you need a vented cap---i bought a so called vented cap that fought me---i ended puttin a .093 hole thru the center rivit
doctordesoto

ps---check your cap after a hig speed run---if it gushes air when you loosten it , your not venting well ---i put the exhaust thru the valance and close to the tank---fuel was getting VERY HOT @ speed---put thermotec wraps on the tail ppe near the tank and thermo tec tape on the sides of the tank---dropped fuel tank temp about 60 deg !!
 

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Discussion Starter #4
if you plugged the closed system will you need a vented cap---i bought a so called vented cap that fought me---i ended puttin a .093 hole thru the center rivit
doctordesoto

ps---check your cap after a hig speed run---if it gushes air when you loosten it , your not venting well ---i put the exhaust thru the valance and close to the tank---fuel was getting VERY HOT @ speed---put thermotec wraps on the tail ppe near the tank and thermo tec tape on the sides of the tank---dropped fuel tank temp about 60 deg !!
i plugged three of the four holes. using one hole to vent through the line that went to the old charcoal canister up front.

trouble shot this issue for a good 1/2 tank of gas, sometimes with the gas cap off. couldn't figure it out. took the top of the Edelbrock carb off and found one float out of whack. hanging way too low, and even when it was hanging, the needle seemed to be hanging up into the seat - it did not fall freely when the float went down. i'm sure the fuel pressure would over come this issue, but still not sure why it was hanging up.

anyway, got the two float measurements correct. cleaned the needle up a bit. test drive was fine, although it did still break down a bit above 85 mph. filled the tank back up and went up the test hill and it worked fine.

all makes sense - one side was getting starved of fuel under high demand. the float would not let enough fuel into the bowl to feed the engine properly, so i wasn't getting full power under a load. seems okay now. not sure how the float got that out of whack.

i will keep an eye on it, but thanks for the ideas-
 
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