I tried Q-Jet(non turbo), Holley and Carter(Edelbrock) on some draw thrus a few years ago and the Carter ran great and was the lightest of all. I did not boost reference the power valves and had a real problem at times with lean mixtures under load at part throttle.
Especially in your app, you can have the engine under heavy load, maybe even boost and the turbo will pull so hard on the carb it will close the power valves and cause a potentially disastrous lean situation.
Over on www.turbomustangs.com they have a thread on carbs and how to boost reference almost anything. I have seen these problems cause bad things if not corrected!!!

Agreed.

Q-Jets and Thermoquads work well with a draw through system because they both have a manual set-up of the primary metering rods that works with the opening of the primary butterflies. There is an APT (Adjustable Part Throttle) which can either raise to enrichen or lower to lean out the primary metering system. The secondary metering system works for the draw through system, because when the system is spooled up under boost, there is enough vacuum in the carb plenum to operate the secondary metering system.

Holley's are easily boost referenced through the metering blocks and power valves.

Traditional Carters (AFB, AVS, Edelbrock Performer, and Edelbrock Thunder carburetors) would need a special metering "plate" that references boost to the (vacuum only) power pistons, to raise the metering rods to the "power" step. They actually run better under "blow-through" conditions.

Running boost without an enrichment system means that you are running either "cutting torch" lean at boost or "pig rich" at during cruise.

The ultimate low cost induction system with a draw through turbo system would be a Throttle-Body Injection system that is boost referenced through the MAP sensor and the spark timing can be retarded by a knock sensor.

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David Gibson

Kipamore,
Why not use an open air cleaner?

Why not use an open air cleaner?

Matt,
That's a good idea, but in this application it probably would be less than ideal. The truck makes cargo runs of 600 to 1300 miles at a time. Moving that much air through the filter, in the rain and snow, dust, bugs, etc would probably lead to clogged filters, or at least it would lead to reduced filter life to have the filter exposed.

I am also planning on experimenting a lot with feeding the carb hot air in an effort to maximize the fuel mileage. Not so much with the turbo setup but with the regular old 1 barrel. Using the regular air cleaner allows me to use some ducting to pick up hot air from behind the radiator.

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1965 Valiant wagon Turbo slant (work in progress)
2000 Chevy 155" cargo van - The Abductor
1970 Newport convertible
1996 Buick Roadmaster Wagon
1966 CruiseAire motor home
1990 Toyota 1 ton box truck TURBO slant (scraped)