Author Topic: A/T and M/T carbs  (Read 263 times)

Offline Erick

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A/T and M/T carbs
« on: November 02, 2024, 09:51:04 AM »
Hi,
What is the difference between an A/T and M/T carb ?

Offline Kenth

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Re: A/T and M/T carbs
« Reply #1 on: November 02, 2024, 12:21:27 PM »
Several, like available vacuum ports, calibration and throttle lever. Any certain year in mind?

Offline Erick

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Re: A/T and M/T carbs
« Reply #2 on: November 03, 2024, 08:28:54 AM »
No, no particular year in mind. After my troubles with the remanufactured carburetor I am still looking for another carburetor, but it is not easy to find here in France espacially M/T carb. And before making another mistake I wanted to know the difference between A/T and M/T carbs. My car has M/T. I've seen on Lars's papers that calibration seems to be the same for Vette A/T or M/T small blocks.

Offline Kenth

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Re: A/T and M/T carbs
« Reply #3 on: November 04, 2024, 02:46:43 AM »
CSB M/T and A/T may very well have the same main jets, primary rods and secondary rods.
But, generally the idle/low speed calibration is richer in the M/T carbs.

What would be the number on Q-jet needed?

Offline quadrajam

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Re: A/T and M/T carbs
« Reply #4 on: November 05, 2024, 04:56:53 AM »
Dont bother with a M/T carb. Not neccessary and usualy have a lot more wear to the moving
parts. Properly built with Cliffs parts and recipe a Q-jet will be fine on a A/T, M/T CVT, Jet drive,
Reeves drive or whatever.

QJ

Offline Erick

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Re: A/T and M/T carbs
« Reply #5 on: November 05, 2024, 11:55:38 AM »
If I'm not mistaken, my car originally came with a Holley (67 SB Vette) but I don't like those carbs, and because I don't have the original one,  I'm looking for a quadrajet for replacement. After a bad experience with a "remanufactured' I'm looking for all the infos before making another mistake. So all advices are welcome.

Offline quadrajam

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Re: A/T and M/T carbs
« Reply #6 on: November 05, 2024, 01:08:27 PM »
Not familiar with older corvettes, Will your intake manifold accept a Q-jet or is it
square bore only?

QJ

Offline Erick

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Re: A/T and M/T carbs
« Reply #7 on: November 06, 2024, 12:48:05 AM »
I changed for a q-jet manifold.

Offline Kenth

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Re: A/T and M/T carbs
« Reply #8 on: November 06, 2024, 01:25:13 AM »
Yes, some 1967 Corvette with 327 uses the Holley 4160 #3810 (with A.I.R #3814).

Other 1967 327/350 uses the Quadrajet.

If you need a proper 1967 Quadrajet i have one 7027218 for 1967 327/350 in very good unmolested original condition (renewed by me) for sale.
It is the third type 1967 and as such it has the upgraded later inlet needle and seat (not the problematic  first membran style). It will be hard to find a nicer one.
And the best of all, i´m in Sweden so shipping cost wont kill you.

Send PM for pictures and info if interested, thank you.