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Picked up another Thermoquad

Paul_G

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My first experience with a TQ was on a 75 motor home engine I bought for rebuild last year. I rebuilt the TQ and put it on the 318 in a 49 Plymouth I was playing with last year. The Plymouth had a Holley 600 on it. The little Plymouth ran so well with that TQ I never put the Holley back on before I sold the car. Kicking myself for not keeping that TQ.

I found another TQ on Ebay. Plan to rebuild it and put it on the 68 383 I am playing with this year. The 383 has a spread bore intake with an adapter plate to fit a square bore carb. I want to get rid of the adapter plate and try a 1" open spacer under the TQ.
 
I just found one on a 440 MH I was pulling the fan and clutch off of. Now you got me thinking to maybe put it on the Holley street Dom intake. Can never have to many carb options.
 
Plus Shipping form SoCal

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There are really only about a half dozen T/Q's that really have any significant value,most are a dime a dozen,threw that many out a year ago.
 
There are basically two common sizes. The smaller 1 3/8" primary butterflies and the larger 1 1/2" primary butterflies. The larger ones are the only ones worth messing with. The smaller carbs are parts carbs.
 
That 1 is NOT what you want.
That is a later model emission carb...yuck
The carb should be model # 9036s or lower, with a curved top plate and not the flat front
 
There are basically two common sizes. The smaller 1 3/8" primary butterflies and the larger 1 1/2" primary butterflies. The larger ones are the only ones worth messing with. The smaller carbs are parts carbs.

Not necessarily,the 71 340 T/Q's 4972/4973, the 72 6138/6139 and the 73 6318/6319 command a premium if you can find them !
 
You just want one with as little vacuum ports on it as possible. No added on features like the one above for a high performance/race application.

The one above would work just fine with mild upgrades but I wouldn’t push it. It is still a capable carb. I would use it in a stock or near stock configuration. It can be modified to perform. It really isn’t hard to do. You just have to know what to do to THAT particular carb. There are a number of variations to the base plate, center section and tops.
 
Not necessarily,the 71 340 T/Q's 4972/4973, the 72 6138/6139 and the 73 6318/6319 command a premium if you can find them !
Yea because there still a good carb that can go on a car that will command a really good price restored despite the later wane-ing year(s) of muscle cars. Think 340 Cuda/Challenger/Duster.
 
Yea because there still a good carb that can go on a car that will command a really good price restored despite the later wane-ing year(s) of muscle cars. Think 340 Cuda/Challenger/Duster.
Right Rumble. And that should be the only reason to pay the higher price. They can all be made to run as good or better than the high dollar early ones.
 
I don’t know about better only because there tunabilty is limited next to certain Holley carbs. Once you go beyond the base Holley, in example what was offered OEM, they can get pretty trick. And this is where I get annoyed with people saying, “Just slap a Holley on it and you’ll make more power!” Or “Do you know how much power your giving up because it’s not a Holley?!?!?!
(Not to mention the same crap when a 6 pack or dual plane dual quad set is used.)

It isn’t always an apple to apple comparison when people say this. But act like it is. Talk like it is. Like it is no big deal. But it is a huge deal.

This is partially B.S. and partially true.

A more modern upgraded high dollar Holley (and there knock off’s) have features a stock carb doesn’t have. OEM Holley’s as well. Now if you add in these features to the old carb (that’s if you can....) you can make greater power over the OEM units.

It would be interesting if a TQ could be upgraded to a 4 corner idle system, multiple air bleeds and a reshaped/contoured air entry. Can they? I don’t know. I haven’t had a lot of good fortune (a good running car to play with) in order to find out just what can and can not be done.

Demonsizzler (now retired) was very good with these carbs. He took a lot of flak over on Moparts years back but stood his ground. He knew them in and out pretty good.
 
I didn't compare them to a holley at all. I'm just saying that a 1984 318 TQ can be made to run with a highly coveted 6139 without much time invested in tuning. And that the only reason to be numbers crazy about a TQ is if it matches your specific car.
 
I never me to say you did
Carter vs Holley comparison.
I didn't compare them to a holley at all. I'm just saying that a 1984 318 TQ can be made to run with a highly coveted 6139 without much time invested in tuning. And that the only reason to be numbers crazy about a TQ is if it matches your specific car.
 
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I'm a thermoquad fan. My 73 340 RR had one, the 6319, but like a dummy when I was 18 I swapped it for a holly, and that was a mistake. Now years later, I have a few around, both large and small bore, currently running a 74 large bore TQ on my beefed up 340 and it runs great.

The only problem with the older carbs and the TQs is finding ones that don't need the throttle rods bushed because most are worn and therefore you have air bleed problems, so loss of performance and usefulness of the carb.
 
Hey Idrivemopar, on the 340 thermoquad did you do any mods like primary rods changed or jets front and rear? And mind sharing part # from this particular thermoquad? Thanks!
 
On my original thermoquad, it was a 6319, I put in bigger primary jets, I believe they were 2 sizes bigger and that was not enough it still ran very lean, I have a bigger cam and higher compression, so I switched to the 6322 thermoquad which is the large bore for 1973. It worked ok,but the throttle rods had some air leakage so I switched to the 9023 thermoquad, which is a large bore from a 74 which I am running now, and its spot on. Its not much different from the 6322 primary jets and metering rods are the same, only difference are the jet tubes on the secondary's, the 9023 is running a 5137 where the 6322 is a 5125. So with the bigger jets on the secondary's and not having the leaking throttle rods, I will most likely continue to run this one.
 
Ahh ok! :thumbsup: Reason I ask is because I will be running a 292/508 mopar cam in my 360. It's in a dart sport with sort of a Joe dirt look!:D Currently run a thermoquad that was on a drag cuda 440. It has worked good. But plan to find a back up so reason I asked in model #/type.
 
Was running a 280/474 mopar cam but felt I needed a little more. Was 3.55s now 3.91's out back. 9.5" FTI 3400-3600 stall converter. 340 X-heads, victor 340 intake with thermoquad adapter.
 
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