Lotus Elan and Lotus Elan Plus 2 Forums

I am putting the finishing touches to my Sprint and am looking to replace the old rubber vacuum pipe that runs from non-return valve on inlet to t-piece on cross member. I am thinking of using silicone as apposed to rubber and would like to know what size pipe I need. Inside diameter & outside diameter would be most helpful.
thanks
Ian

Tricky.

You need a pipe that won't 'suck flat' but I don't think you will usually find that in the specifications.


The wall thickness for negative pressure (vacuum) will need to be much thicker than for the corresponding positive pressure.

The pipe was orginally black nylon tube the same as ran to the head light pods and to the dashboard switch. This used a short length of rubber fuel pipe hose which was resitsant to the fuel to join at the tee and vacuum tapping.

cheers
Rohan

Ian
The Hard Plastic Pipe is 5/16" O.D. or if it is easier to get Metric Version 8mm O.D. if you are going for Silicone Connecting Hose I would use 8 ID x 12 OD that will give you a wall thickness that will not collapse in vacuum, and use "Mikalor" 12-14mm Spring Clips to hold it on.
At least that is what I did on mine

Many thanks for all your replies guys, I knew someone would have an answer
Ian

Give Sue Miller a call, she has it in stock.