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Vac Advance when engine is cold


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On my brat I want to hook the vac advance on the disty directly upto the ported source off tha carb. The reason for this is when I stop and let the car cool down for a few minutes after being warmed up i think the vacuum valve closes (meaning no vac advance) and when i start it again the you can put your foot to about 3/4 throttle and hardly any acceleration and you have to floor it to get any accelleration. This causes the power to be kindof all or nothing so it makes things a bit jerky. After I drive it for a while I supose it heats up enough to open the valve and she feels normal again (not having to floor it to make it go anywhere).

 

Why did the subaru tech's not want vac advance when the engine is cool?

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Less advance = lower emmissions. So they had the advance cut off under a certain temp (on some years and models, but not all. MANY systems were employed - some even had electronic timers and stuff associated with em). Anyway - feel free to bypass it and run a new line directly to the carb. That's what I did anyway.

 

Basically a cold cylinder wall causes condensation to form and since liquid gasoline doesn't burn it gets shot right out the exhaust. Keeping the advance low causes the cylinder to get hotter due to compression and helps to reduce this effect. There's some other principles involved, but that's a start for you.

 

GD

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After I bought some vac line and opened the hood I realized that the vac line for the vac canister was disconected (must of forgot to reattach it like a week ago when i was playin). Could the situation I described in my previous post happen because the bowl on the carbi could not vent into the vac canister?

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