Idle Vacuum?

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Idle Vacuum?

Post by CBDZ » Wed Dec 07, 2016 11:58 pm

I've been playing with idle settings, both fuel and timing. At max, i can only pull 14 in-Hg of vacuum. All the research that i have done states that i should be pulling a lot more. are these numbers that i read about (20's) for vacuum only for a V8, or should i also be pulling that in my small flat-4?

other than what seems to be low vacuum, i can get it to idle smoothly at 900-950 rpm.

engine specs = 1904cc, 110 cam, 40x35.5 valves, 8.3:1 compression ratio, german intake plenum, with single tb and idle control valve (fully closed at idle)
My Car Details:
Fiberglass Buggy on 1973 Chassis.
1904 cc
Megasquirt (MS1 with 3.57 board) Fuel Injection: German Intake Plenum, CB Performance End-Castings, Ford Escort Throttle Body with custom Adapter, MS controls Wasted Spark Coil Pack

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