"Carbs"

The local auto parts store only carries 1/4-in and 3/8-in fittings and hoses. Is there some special metric size for these? Stuff on the web seems to be conflicting.

Thanks for your help.

Its 5/16" (actually probably some metric hose)

That is why I drilled and tapped the port and installed a 10mm X1.5 adapter to 6AN.

The way I got around it temporarily was to buy two of those glass view fuel filters at your FLAPS.
They come with every possible thread in adapter.
Put the 3/8" on one end and the 5/16" on the other end and you have a 3/8" to 5/16" adapter.
I am no longer using those and woudl partwith them if you want.

Or JEGS has 3/8 to 5/16 brass couplers for ~$5 ea.

Should be 5/16, or more specifically, 8mm. 5/16 is commonly available. Do yourself a favor though and spend the extra few bucks on Goodyear 30r9 or other ethanol-rated hose. Chris at Tangerine Racing can sell you the length that you'll need.

Thanks George & Stu. You both have been very helpful (and patient) with my "single to dual carb" questions over the last year.

I guess I need to check the size of my existing fuel line and filter, if both are 8mm, I'll just order Chris' hose and 5/16 brass T... that should take care of it.

Gates SAE 30R7. 3/8 (9.5mm). Don't use the slotted screw type clamps.

The fuel-injection style (non-slotted) clamps are available locally at any FLAPS, but if you order from Chris, I'm sure he'll send some with you.

30R7 works great as well, but I went with 30R9 to deal with ethanol so I wouldn't have to worry about them ever breaking down, at least in the next 5-10 years.

I cut these off of my webers last week:


8mm is .315 in. and 5/16 = .3125

So I could do this:


And I prefer the hose clamps you can see in that pic.
They are similar to the slotted screwdrive, but the slots are only impressions so they cant cut into the hose.
I think I got them from Jegs.

Thanks again fellas!

-Don