Which port should I use for the PCV valve and C4 vacuum modulator? I’m thinking the larger one goes to the PCV valve, and the smaller to the modulator. Thoughts?
DIHLON
Which port should I use for the PCV valve and C4 vacuum modulator? I’m thinking the larger one goes to the PCV valve, and the smaller to the modulator. Thoughts?
Pro Flo 4 Help
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Which port should I use for the PCV valve and C4 vacuum modulator? I’m thinking the larger one goes to the PCV valve, and the smaller to the modulator. Thoughts?
I don't have a proflow but that would make sense to me. The original carbed vacuum port for the PCV uses a large hose like that. The vacuum modulator uses just a small hose for a signal. Actual flow of combustion gasses are needed through the pcv, if you use the small port the motor might not be able to evacuate all the crankcase pressure and that leads to blown seals.
I run the PCV off the front of the TB and the brake booster off the large port on the back. I remember the directions being pretty clear on what went were.
All ports are full-time vacuum so either 3/8" port will work for PCV but I'm guessing the front port might draw from the center of the TB?
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