Vacuum Hose Sizes, Total Lengths, and Sources?

[Red-Arrow]

I just bough 10 feet of 4mm silicone vacuum hoses from siliconeintakes.com It was cheaper to buy it from their website than Ebay.

They claim the wall thickness is 3mm on the 4mm ID hose. most listing which give this info state 2mm side walls which is the kind that can collapse with heat and vacuum I guess.

The rubber elbows are all wasted and leaking on my car giving me the 315 fault code. I'll just replace them with this silicone hoses as they flex around my finger without kinking. Why would I pay $3 for a 2 inch elbow hose when I can replace the lot with quality silicone ones?

[t5ftw]

I need to know the inside diameter of the following hoses. I assume the hoses connected to TCV are all 4 mm, correct? When I measured the OD, the red one was 10 mm, the yellow one was 9 mm, and the blue one was 9.5 mm. However, I could not measure the exact inside diameter because they are all enlarged over time especially at the end. Maybe I could have tried cutting the hose in the middle but I need to drive this car until I get the correct hoses.

#4 hose I guess 6 mm, correct? Or, is it 8mm?
#5 hose must be 3.5mm because it seem the thinnest and the thinnest in the kit is 3.5 mm.

One more question. What do you guys use for brake booster vacuum hose? I picked up 3/8 ID fuel line from advance auto part, but it is not as thick as the one that I am going to swap out. I checked out Autozone and O'reily, and they showed me the same stuff. The original hose seems more stiff as well. The guy at the part store told me that it gets stiff as it exposed to heat over time. But still it is not as thick as the original one. If it is normal vacuum I would just try without much of hesitation, but this one is for brake. So, I would like to hear your experience or thoughts.

[Red-Arrow]

Fuel line hose is very strong. there is not problem using it, juts make sure you clamp the ends down.

[jblackburn]

I assume the hoses connected to TCV are all 4 mm, correct?

Yes. You may want to get about 8 feet for that alone - I used 3/16" line and got 10 ft and had 2 or 3 left over that I used other places.

The purge valve hoses I don't know about - I'd suspect 6 if the brake booster hose is 8.

[t5ftw]

I managed to replace all the lines from the purge valve to both the intake manifold and the air pipe using fuel line hoses. I used 3/8" from the purge valve to the tee and from the tee to the both check valves, and 11/32" from one of the check valve to the air pipe. I don't recall what size I used for the line between the check valve and intake manifold, but I I used the smallest one from O'Reily. either 1/4" or 5/16". I think 3/8" hoses are definitely larger than the original hoses, but they were easier to put on, especially at the tee. I clamped every end. It is not quite tight at the purge valve. So, next time I will use either 5/16" or 11/32". The problem was that the tee barb is much fatter than that at the purge valve and the air pipe. I don't know how critical it is to use correct sizes in terms of performance, but this job made a noticeable difference in mileage, pickup and braking power. However, I am not seeing any change in my high LTFT. The brake booster hose is a non-metric hose and the size 3/8" ID which is approximately 9.5 mm. It is possible that my hose is not the original, and replaced by one of the previous owners. Now, I need 3.5mm and 4mm hoses to swap out turbo vacuum hoses.

[jblackburn]

Oh hey.

All the lengths you'll need! For a turbo anyway.
http://volvospeed.com/vs_forum/index.ph ... se-how-to/

[t5ftw]

Oh hey.

All the lengths you'll need! For a turbo anyway.
http://volvospeed.com/vs_forum/index.ph ... se-how-to/

I just ordered 8 feet of 4 mm and 3 feet of 3.5 mm from Hose Techniques. Not the kit. I still suspect the hose from intake manifold to turbo is 3.5 mm. I asked them if their hoses are inch-based or mm-based. They said their hoses are exactly mm sized. Their hoses seems pricey but look quality hoses as they say using Platinun-cured silicone.

Edit,: oh, man. I just took the blue hose out from TCV and measure the barb diameter. It was 5.5mm. Guess I am gonna change my order.

[Red-Arrow]

I replaced almost every hose and got away with using 4mm silicone vacuum hose. The stuff from www.siliconeintakes.com is much better than I hoped for. the side wall is huge and its looks like lovely red liquorish! the 4mm hose is 10mm in total OD.

Very impressed with this hose and would recommend them highly, very fast posting at a good price. I'll post some pictures tomorrow.

[t5ftw]

I finally, replaced the hose from the intake manifold to booster and the one from the joiner in between to the ETM pipe. What a difference! Braking power improved significantly. My original hoses didn't show any visible deterioration. They looked just fine. But I decided to try out new hoses, and I am so happy that I did. I used transmission oil cooler hose. Apparently, there are power brake vacuum hose manufactured by Goodyear, Gates, and such. Autopart stores list them on their web sites but they don't stock them. Fuel line hoses looked thinner than power brake vacuum hoses. Trans cooler hoses do not satisfy the standard that booster hoses must meet such as Ozone resistant. But its real cheap and strong enough. I am going to keep a 3 feet fuel line hose in my trunk just in case.

[gmh]

I replaced almost every hose and got away with using 4mm silicone vacuum hose. The stuff from http://www.siliconeintakes.com is much better than I hoped for. the side wall is huge and its looks like lovely red liquorish! the 4mm hose is 10mm in total OD.

Very impressed with this hose and would recommend them highly, very fast posting at a good price. I'll post some pictures tomorrow.

+1 on http://www.siliconeintakes.com . I got the Silicone Boost/Vacuum Hose Engine Dress Up Kit, Blue which is 10ft 4mm, 8 ft 6mm, and 4 ft each of 8mm and 10mm. $30 plus tax (we are both in Colorado) and shipping $10, about $1.50 per foot, delivered in 2 days. Hoses have very thick walls, much thicker than the 6 mm that came with the IPD TCV I put in my wife's car. I did all the vacuum hoses in my 850 including the brake booster and also the coolant overflow hose and have a bunch left to use for "dress up" if I ever get to that. Great deal!