how to tell weber 46?

[jwetering]

I am just a hair's breath away from having an engine built with weber carbs and high lift cams....a couple of questions for you guys:

1) Is it the weber 46 that I want/need for my 3.0 litre?

2) How do I tell if the carbs I have lined up are the corret model?

3) I sthere any way to tell if the cams are "S" cams?

I'm not to worried at this point about jetting etc. for the carbs. BA's book has some suggestions, and I will have the carbs set up initially by a local "expert". I just want to make sure I'm styarting out with the right equipment.

Thanks for the help guys

[ttweed]

If you have BA's book, then you know that he recommends the 40mm Webers for that application, no? On pgs. 145-149 of the second edition he talks about using 40IDA3C carbs with 34mm venturis for the 3.0 carb conversion. He even recommends the 40s for a 3.2 conversion, w/ 35mm venturis, and only goes to 46s with a 3.4 hotrod motor. That said, I have seen quite a few 3.2 conversions done with 46s, and my 3.4 has 50mm PMOs w/ 44mm venturis. It depends on which cam and heads you use, I think.

You can tell which model they are by the identifying stamp on the float bowls, or by simply measuring the throttle body at the bottom.
Look for the stamping right below the cast "WEBER" name. BTW, if you need a set of 40s, I will sell my set (pictured) for $800, but they are set up for a 2.0-2.2 currently.

The "S" cams can be identified by part number, although other similar grinds are available from other sources (Webcam, Elgin, JWE, etc.).

Good luck with your project,
TT

[cstreit]

Is this for a street car or track car? On a street car, 46's will probably not be to your liking. THey will be a bit peaky and have very little low end power... 40's are a better option...

...but that's nto the question you asked is it? They will have a marking on the side as above, except with "46" instead of "40".

The correct model will look like the ones above...