Rapidly moving vacuum gauge at idle - smooth above 1k

General engine tech -- Drag Racing to Circle Track

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Firedome8
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Re: Rapidly moving vacuum gauge at idle - smooth above 1k

Post by Firedome8 » Sun May 20, 2018 9:19 am

A leak down test is a good next step. You can inrich the mixture at idle with propane to see if the engine wants more fuel. Just thinking.

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bigblockmopar
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Re: Rapidly moving vacuum gauge at idle - smooth above 1k

Post by bigblockmopar » Sun May 20, 2018 9:40 am

Just did a compressiontest with a screw in type gauge.
All cylinders were between 208 - 210 psi, except cyl. 6, which had ‘only’ 195-198 psi.
Engine temp was around 135F, carb at WOT.

I did 2 tests in a row, one bank at a time from front to back: 1357-2468-1357-2468.
First round I got numbers just above 200-205 psi, second round I got the numbers mentioned above.

So my focus is on cyl. 6.

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