67 L-68 Carb Jetting

[Tim S.]

I need to know the "factory" jet size for the tripower center carb 3660.
Also what would be a recommendation for 5500 ft elevation. Also, are there any metering plate differences for high altitude.
Thank you
Tim

[Larry M.]

Re: 67 L-68 Carb Jetting

Tim:

According to the 1967 Chevrolet Chassis Service Manual, the #R3660A center or primary carb jetting is #64 jets.

The #R3659A secondary carbs jetting is shown as .076

I don't know what to recommend to you at this time for the elevation changes you mentioned.

A lot of Holley carb information is available on the Holley website in their Technical Information section. Check-out for additional carb settings and/or tuning recommendations.

Larry

[Clem Z.]

Re: 67 L-68 Carb Jetting

the area of the jets should be reduced 2% for every 1500 feet above sea level. a #64 jet has a .064 dia hole and the plates in the end carbs have a .076 dia hole. reduce the AREA of these by 6% and you should be in the ball park