Who is the weber whisperer? 40 weber Ida, Largest displacement engine on 40mm

[vintagecarlover]

Just a quick question what's the largest displacement engine that will run properly on 40ida webers? 3.0? Can they be modded to run on 3.2 and if yes what needs to be done and who needs to do it?? Who is the weber whisperer?

[blucille]

paul abbott....performance oriented.

[jmz]

3.2 will run fine with 40s. One of most fun cars I remember was a friends auto-x car with a stock Euro 3.2 with a set of Weber 40s on top. ...amazing torque and hole shot for auto-x.

[zedsn]

Paul Abbott is the man!

[gamin]

Paul Abbott is the "weber whisperer". That description fits for sure.

[Trackrash]

Depends what you mean by run properly.

Conventional wisdom, Weber, and Bruce Anderson say 3,0 is the limit for a 40mm Weber.

There are lots of variables, however, like how is the car driven, and what mods have been made to the motor. Do you want top end power on a hot rodded 3,0, or a torquy stock 3,2?

I know more than one guy running 46 Webers on 3,0s without problems.

As mentioned above some have had success with 40s on 3,2s.

That said, it is possible to bore out Weber 40s to a larger size, I believe to 42mm. And the throttle shafts can be thinned....

http://www.performanceoriented.com/

[jpnovak]

You have to match the airflow of a particular engine with the intake velocity and rpm range of the power band. For example, a stock-internal 3.0 will run fine on Weber 40s and yet a cam change to shift the rpm will not flow enough air and be limited at the upper rpms.

A 3.2 would actually want something like a 42mm but those are custom (Paul can make them). 40s will work and are great for the street but will become a limiting factor at the upper rpm range. Whether you notice it or not depends on your driving style and how much time you spend above 5K rpm.

[1QuickS]

Per Gordon & Jamie, it all depends upon engine particulars and application.

I have a throttle body and main venturi sizing chart on my web site that will provide some perspective:

Performance Oriented

[vintagecarlover]

Gordon. Jamie. And others including you, Paul thanks for the heads up. And info. In next week I'll be reaching out to Paul for carb assistance. Thx again. Mark