Map line source

[hiltonlo05]

I'm curious what the consensus is on vacuum line sources...I'm routing everything in polished aluminum hard lines so I'm trying to get it right the first time.

Directly from the throttle body I'm pulling the following lines.

1-dedicated power brakes
2-shared headlight actuators, hvac controls, general vacuum to car accessories.

I need to drill my manifold for additional sources, can I share the vacuum signal between Transmission modulator, MS3 map sensor, and fuel pressure regulator? Meaning only tap the manifold once and tee all three of those into the same place. Will that alter the signal to the map or FP regulator and cause tuning issues?

Thanks

[Matt Cramer]

The vacuum modulator and FPR are mostly using the manifold pressure as a signal and should not be a problem for the MAP source.

[hiltonlo05]

Thanks Matt,
I didn't think the modulator or regulator would cause any detectable fluctuation in vacuum map signal but wasn't positive.

I assumed using the same line as the brake booster or headlight actuator could cause vac signal to drop as those items where activated due to their heavy demand.



Here's a pic for just a taste of the madness... I'm a fan of polished aluminum obviously.

[billr]

I have mixed feelings about the trans modulator; not too much flow there, but certainly more than the MAP or FPR. I guess I would keep that separate, by itself. I don't imagine you will be flipping the head-lights up/down too often, but agree that I would also keep them, the HVAC, and wiper door (you probably don't have that) separate from all the sensors. Stock though, the trans modulator and dizzy advance and all that other stuff came off a single 3/8" pipe port, only the brake booster and PCV were separate.

[hiltonlo05]

I could add an addition tap to the manifold just for the MAP sensor, but I was trying to avoid another line if possible. The factory Trans modulator line is 5/16" or smaller hardline and the actual nipple on the modulator is like 1/8". I'm feeding it with 3/8" line which I'm hoping can act kind of as a "reservoir" of vacuum, so when the modulator diaphragm moves in and out it won't disrupt the signal to map sensor.

If the consensus is that it will present tuning issues sharing, then I will add another dedicated line.

[billr]

My vote (guess?) is the MAP, FPR, and trans mod can all be on the same line.