4L60e Vacuum Modulator Mod..
Thread Starter
Pro
Joined: Apr 2003
Posts: 552
Likes: 13
From: Oz
4L60e Vacuum Modulator Mod..
Hello,
I am just about to start rebuilding my 4l60e with a street/strip rebuild kit from pro-built www.700r4l60e.com
One of the options he offers is the kit to replace the electronic force motor pressure controller with a vacuum modulator. The benefits are said to be a quicker downshift (no delay), and higher line pressure when making a WOT 2-3 shift. Line pressure would normally be 170-185 psi with the PCM, and 220-235psi with the vacuum modulator installed.
So who has done this, and whats your opinion?
TIA.
I am just about to start rebuilding my 4l60e with a street/strip rebuild kit from pro-built www.700r4l60e.com
One of the options he offers is the kit to replace the electronic force motor pressure controller with a vacuum modulator. The benefits are said to be a quicker downshift (no delay), and higher line pressure when making a WOT 2-3 shift. Line pressure would normally be 170-185 psi with the PCM, and 220-235psi with the vacuum modulator installed.
So who has done this, and whats your opinion?
TIA.
Drifting
Joined: Nov 2003
Posts: 1,539
Likes: 3
From: South al
all FLP transmissions are vacuum modulated & some of the best built a4s in the country i would definatley go with vacuum modulation i would have to tend to think there more reliable than the pcm shifting it
Thread Starter
Pro
Joined: Apr 2003
Posts: 552
Likes: 13
From: Oz
Originally Posted by fsuforever
all FLP transmissions are vacuum modulated & some of the best built a4s in the country i would definatley go with vacuum modulation i would have to tend to think there more reliable than the pcm shifting it
Well the PCM still controls the shifts, the only task the modulator takes away is the line pressure control.....
Drifting
Joined: Apr 2002
Posts: 1,614
Likes: 1
From: DFW TX
Like mentioned above, everyone with an FLP trans, and most other built transmissions go vacuum modulated. You will need to run a hard line back to the transmission for vacuum, but it's worth it.
I have used ProBuilt's vacuum mod. kit and it works great, good consistent shift quality.
I have used ProBuilt's vacuum mod. kit and it works great, good consistent shift quality.
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Pro
Joined: Jun 2005
Posts: 734
Likes: 0
From: Austin TX
Your local transmission supply store should have it. Not your local transmission shop, but the retail supplier. I think the kit runs ~80 bucks. It's a pretty easy install from what I remember. Drill a hole in the tranmission case. Uninstall the force motor and install the vaccume modulator. (don't even need to drop valve body) Run the rubber hose from the vaccum mod to the fitting in the hole you drilled. Run the hose from the outside fitting and into the T fitting that you have intalled in your brake booster hose.
