Carter Thermoquad

'69FuryIIIConvertible

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Looking for advice and information on the TQ.

I know that they came in different CFM's, however when I have tried to research them, I haven't found any good information about the applications that used what.

I'm in need of 3 of them, one for a 73 440 HP, one for a 74 360HP, and one for a 318 4 barrel AHB.

What I want to learn is which TQ is my best option for each of these applications, I don't care about them being numbers matching or correct, I just want carbs that will work right for my applications.

Nick
 
Are you looking for these so that you have correct to the car equipment or do you believe them to be better for your application?
 
From the factory in general 318-340 got the 800cfm while 360 and big blocks got the 850. Roughly 1975 and prior, stick and auto carbs were different. Stick cars got a two stage accelerator pumpshot. Some time around 1976 all got the two stage pump shot. As far as finding the perfect one to just bolt on, I think they all need a little doctoring for today's fuel. I would stay away from the lean burn carbs, they have no port for vacuum advance. Also most don't have an idle speed screw! If you haven't checked out the( Vaanth guide )yet do so, and bookmark it.
 
Are you looking for these so that you have correct to the car equipment or do you believe them to be better for your application?
I just want something that will be better for my application. I've been looking at a 9111S for a 78 440 W/O cats.

I just don't want to end up with a carb that won't work with my engine. I love the TQ, I've worked on a few, but they were OEM for the application.

Nick
 
I just want something that will be better for my application. I've been looking at a 9111S for a 78 440 W/O cats.

I just don't want to end up with a carb that won't work with my engine. I love the TQ, I've worked on a few, but they were OEM for the application.

Nick
I have the T-Quad from my 79 E58 300 that I will likely never use I will check the number and let you know. The E58 was a HP engine no cats
 
Please do. And if you would like to sell it. Please let me know.

Nick

I will be happy to have you take it off my hands Nick even though I believe in friends don’t let friends run T-Quads :poke:

I likely won’t be able to hunt it down for a few weeks if that’s ok? Heading to Florida Sunday
 
The early not '71 are better, the cruise jetting will be closer to 14.5-7. the lean burn models regardless of cfm all calibrated towards 16:1 (Steve could probably confirm). WOT on lean burns are not lean, still calibrated towards 12.5:1. The lean burns also do not have a ported spark advance, the box on the air cleaner was plumbed to manifold vacuum. You can modify the lean burns for ported spark advance. To correct the lean cruise you can file a flatspot in the fatter sections of the metering rods, they come out in about 2seconds. The more refined option is to buy Eddy replacement rods and shorten and rebend (they are longer than TQ rods)
Hope this helps.
I'm switching to my Frankenstien TQ I built out of 360 truck carb and lean burn parts.
 
I like the TQ better than a similar QJet, by a long shot. The main part of the carb you're going to use will be the primary side, which should be 1.375" primaries. How much total capacity with the secondaries, to me is not that important. KEY thing is getting the fuel curve calibrated for the individual engines! NOT so much the ultimate CFM rating. As they ALL are way bigger than what the engine really needs.

Use the FSM for each engine for the guide as to OEM fuel calibrations. Mainly the main jet and metering rod combinations, primary side particularly.

I put the TQ9801 on my '67 Newport (replacing the OEM AFB and manifold) with the allegedly matching Torker 383 intake. Both allegedly matched to each other? Had to make sure to use the thick OEM-style base gasket for best WOT performance. Otherwise, not very impressive. Not the mpg increase I was looking for OR anywhere close to what some '74 Chryslers produced in an economy run. Pulled it off and sought other options.

Otherwise, I've got both a 650cfm Street Demon (phenolic float bowl for that TQ look) and also an AVS2 for a Chrysler 383 application.

Just some thoughts,
CBODY67
 
The Torker intake will give up economy on every engine it's bolted to. Most will lose power in the ranges you need it too. Loose that and use a modern dual plane and your mileage should be much better. All Thermoquads now need a good tuner, who understands modifying the fuel curves. Lean burn units I steer clear of, but only because IMO they need more work. Another thought is the new Demon carb that is based on the Thermoquad but use new parts and can be tweaked much easier.
 
The reason I went with the Torker 383 was due to its basic design of more even mixture distribution to the cylinders, volume-wise, than the normal dual planes of that era. Which was the reason behind the original Tarantula intake it was based off of. The Torker was more mid-range oriented than the Tarantula, being made from a discarded Tarantula manifold found in Edelbrock's scrap heap by an employee who needed something for his SBC ElCamino. When it ran better with that one, discarded for less lower rpm horsepower on the dyno, then the Torker series was born.

In more recent times, we've learned more about single planes vs. dual planes in how they act and can be tweaked with plenum dividers and such. But still about every cylinder getting an equal air charge, as modern FI intakes seek to do. Just as we've learned much more about lobe centerlines on camshafts, with time. At the time, the "equal mixture distribution" orientation was the latest, greatest thing for ultimate power, too.

I always liked the TQ much better than the QJet, if for no other reason than you don't have to remove the accel pump arm (with a hammer and punch) just to get the airhorn off. In some respects, it's a hybrid metering rod carb. Why? In the throttle body, there is a long,skinny "flapper" which is run by a cam attached to the primary throttle shaft. It touches a rounded-end rod on the bottom of the power piston (which runs the metering rods up and down against spring pressure). So, unlike the prior AFB and AVS carbs where the power pistons were independent and worked ONLY against spring pressure, the flapper/cam/rod arrangement is a default lean mixture regulator, no matter what. Didn't realize what it was or did for years, but probably had to be related to emissions or such?

To be sure, the TQ looks impressive with its "high tech" float bowl material, physical size, and just the way it looks. MUCH larger float bowl capacities than the QJet, too! But it's also a bit taller than a similar Holley 4bbl.

When I saw that Holley's Street Demon carb had so many similarities to the TQ, including the line feeding the accel pump housing, I was amazed and impressed. Gave credibility to the prior thoughts I had about how good the TQ design was. I suspect that if Carter was still in business, there would have been an "infringement" lawsuit happening, or a request for "licensing" of the design, at least. But I'm glad Holley did that, with a few changes to make it a more useable carb.

Just some thoughts,
CBODY67
 
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