Vacuum Hose Size

[Nash]

Hi Guys. Sorry this is probably against the dreaded rules, but I am unable to get to my Leggie today and I really need to get some Vaccum Hose before I can drive it and I need the car tonight...

My question is, what size is the Vacuum hose that goes from the pre thottle body inlet pipe to the Factory Boost Controller/Waste gates ? (The one where you put an MBC/EBC on)...

I pulled out my MBC as I keep getting fuel cut under load and the hose was so perished it fell apart when I took it out.

 

[southlandVR4]

Sorry to revive a dead thread but I'll add my 2 cents. It was mentioned in another thread that it's 4mm for Vacuum hoses. Using my digital callipers, I measured the red tipped hose from the intake and the vacuum hose coming off the back of the plenum. 6.5mm was what I measured the barb on one of the turbo lines so 6mm should be correct.

 

[dma]

Recently replaced all small-diameter hoses (4 mm and 6 mm).
Also moved the restrictor into the hose with the red marking (this slightly speeds up the response after the turbo actuator control solenoid opens).
Here is my setup.

 

[dma]

In the standard setup, the restrictor is installed in the hose at the point marked with red paint.

6a13tt factory hosing diagram

 

[mezje]

View attachment 66934

Recently replaced all small-diameter hoses (4 mm and 6 mm).
Also moved the restrictor into the hose with the red marking (this slightly speeds up the response after the turbo actuator control solenoid opens).
Here is my setup.

This is an awesome image and will be sure to help others in future, thanks for sharing.

 

[dma]

I measured and replaced the remaining hoses. I’ll leave the diagrams here in high quality.

Since the forum compresses image resolution and doesn’t allow uploading SVG files, I’m including a link to the original files. https://drive.google.com/drive/folders/1lESpeN0758pjIF6tFlXFxtsnIhzX4auI?usp=sharing