Thermoquad or Holley?

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I'm partial to the thermoquads. Have been running one for 13 years straight never any issues @ all related to the carb! Only once my brass floats (reused) originals developed pinholes and sank therefore flooding my engine cylinderd full of fuel! I thought my engine had locked up. Which it did with all that fuel. But replaced floats with new ones all good!:eek::steering:
 
I have been having a lot of trouble out of my holley double pumper, since I bought the car last year. It has a oversized cam and I don't know any of the engine spec's. My intake is the old Torker 340 and the car needs a stall converter really if i keep running the current setup. I have no low end torque. I keep getting gas in the oil from the Holley its old and been rebuilt several times. A good buddy of mine gave me a New rebuilt from Chrysler thermoquad, it's for a 1977 400 HP engine. I can pick up a intake from another buddy, he has a stock 340 cast iron intake 71 casting he also has a wiand spread bore he'd sell me, I'm leaning toward the original cast iron because I can use the choke, what do y'all guys think, should I just buy a new holley or switch to a dual plane and use the thermoquad and maybe gain a little low end torque?

Definitely try the TQ and 71 cast iron intake, what have you got to loose. You will be faster all around and actually get OK mpg as a bonus. I ran a mechanical advance only distributor for years. No problem there.
 
A streeter with street gears and a street TC,needs a Vcan, IMO-period. And I highly recommend the biggest one you can find, or to mod yours out to 20/24 degrees, and to reduce the power-timing a tad if you have to. There is no other way to give the engine the PT timing it is so hungry for, and therefore the torque-delivery suffers. In other words you always have to drive deeper into the carb than you would if you had a Vcan. Then you have to increase your idle-timing in an attempt to overcome that,and speed up the advance curve, and in the end you have to run 91 instead of 87E10. And your car sucks gas on the hiway bigtime.
Now if you have 4.30s or something in the back and a 4-speed, this becomes less important..... altho I still recommend the Vcan for other reasons.Personally, I left my no Vcan, dual-point,top-bearing, race D on the shelf in 1999. If I knew where it was I would put it up for sale;I'll never need it.

AS to which carb and intake; I'll throw in with the factory CI intake and TQ, guys. I love those carbs for so many reasons. On the street you will be hard pressed to measure better results with any other combo. And I made mine work really well with the Mopar292/292/108 cam, about the biggest cam anyone would ever want to run on the street. It's pretty big
 
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I wasn’t so good n love with it on the street, unless it was light to light. Good bracket cam.
If you are talking about the 292/108, I agree . It was only in my engine for about 7 or 8 months, just long enough for me to have moved it this way and that way and thrown a few intakes and carbs at it, and burn off a few tires,lol.
But if talking about the TQ, sadly I also agree with you. As much as I loved that TQ, I soon dug up my old Holleys
But that TQ ended up on my winter engine from then on
 
Cam before carb.
If you are talking about the 292/108, I agree . It was only in my engine for about 7 or 8 months, just long enough for me to have moved it this way and that way and thrown a few intakes and carbs at it, and burn off a few tires,lol.
But if talking about the TQ, sadly I also agree with you. As much as I loved that TQ, I soon dug up my old Holleys
But that TQ ended up on my winter engine from then on
 
Holley leaking fuel on shut down = float to high.

Holley > thermoquad any day and twice on sunday.
 
Today I picked up another TQ that may be better than the newer one I have it's a 6518s was told it came off a low mileage motor home with a 440 but I didn't see this number on the TQ I'd list, it doesn't appear to have any smog stuff at all.

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I have it in my list 6518 - says H-440-3 Chrysler Industrial 1.5" Pri Bore
That's all I got.
 
1.38

It is a noticeable difference in driving the car. The smaller primary is best used on a stock 340 for the largest engine. I used it on my ‘79/400 B engine. I did live with it for a while. It wasn’t bad. But it was very noticeable when I swapped the larger carb in.

In a performance small block oriented scenario, the 1.50 is what your going to appreciate driving around on. Always on a big block if you can. The 273/318 can use the smaller primary carb for a long while in a performance application very well.
 
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1.38

It is a noticeable difference in driving the car. The smaller primary is best used on a stock 340 for the largest engine. I used it on my ‘79/400 B engine. I did live with it for a while. It wasn’t bad. But it was very noticeable when I swapped the larger carb in.

In a performance small block oriented scenario, the 1.50 is what your going to appreciate driving around on. Always on a big block if you can.
I meant what is the CFM difference? The 1.5 is an 800, what is the 1.38?
 
Im disappointed about my intake, my buddy told me he had a 71 casting and after I went to get it, its a 73 with the electric assist choke, I'm hoping it will still flow as well. Recon I need to keep looking for a 71?

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No, basically idntical intakes. IF you have jets in the floor of the intake, you can plug them up. The electric choke assist can be a plus. That is the resistor to it.
 
Im disappointed about my intake, my buddy told me he had a 71 casting and after I went to get it, its a 73 with the electric assist choke, I'm hoping it will still flow as well. Recon I need to keep looking for a 71?

No EGR you are good to go. Get the truck choke, without the heater, or use as is. Flow is pretty much the same.
 
Thermo-Quad, Quadra-Jet, AVS, AFB, WCFB, Autolite > Holley unless you like having to work on your Carb.
Yep, agree, I've always had real good luck with AVS, and TQ's on my cars in the past, I've only had 4 cars with Holley's and trouble with every one, maybe ive just never had a good holley but every carter ive rebuilt has ran like a champion, I even rebuilt the TQ on my 73 Cuda back in the 80's and it ran great. I've rebuilt 2 Holley's and never could get them right, one was a 600, the other a 750 dp. Guess I just don't get along with Holley's.:)
 
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