Thermoquad replacement suggestions

[Charlied]

With the helpful advice and encouragement of you guys, repaired ( fuel bowl leak) my thermoquad, thanks again to all.
But if it acts up think I ready for something brand new. Do not want to change the stock intake, which is a spread bore.
Looking for something that will bolt right up and reliable, nothing exotic or super high performance, really just plain vanilla. What do you think?
Thanks

 

[Tman100]

Adaptor spacer and a 800 AVS 2 from edlebrock. part number is 1913. I’m a big thermo quad fan but strip kits are hard to find to super tune them all. The edlebrock is my go to. They work well once tuned and leaned out… they seem to be pig fat out of the box.
Just my 0.02.
I like the quick fuel carbs as well as their price point is quite good.

 

[Photon440]

With the helpful advice and encouragement of you guys, repaired ( fuel bowl leak) my thermoquad, thanks again to all.
But if it acts up think I ready for something brand new. Do not want to change the stock intake, which is a spread bore.
Looking for something that will bolt right up and reliable, nothing exotic or super high performance, really just plain vanilla. What do you think?
Thanks

When the Thermoquad went out of production after 1984, Chrysler switched to the Rochester Quadrajet which is also a spread bore.

 

[super-bee_ski]

When the Thermoquad went out of production after 1984, Chrysler switched to the Rochester Quadrajet which is also a spread bore.

Love those Quadrajets!

 

[496 polara]

Street Demon - Holley

Just one option of many.

 

[GTX JOHN]

Holley made several 650 and 800 spread bore carbs.

I think there is one or two around the shop.

 

[BSB67]

Street Demon - Holley

Just one option of many.

It’s note a spreadbore carb, so still needs an adapter, I think

 

[WileE]

I wouldn't be so eager to swap out the TQ. If you got it corrected, bingo ! Yes, the Quadrajet is an excellent carb as well, that would be my reluctant next choice.

 

[4vnut]

I just can't fathom a Quadrajet on a Mopar. True, when right, just like a Thermoquad, they are excellent carbs however I couldn't put Thermoquad on a chevy either. They just don't go together.

 

[GTX JOHN]

They were available for a couple years.
Especially common on(84 to 86) trucks and cop cars.
used a lot on Superstock Mopar as much easier to tune than
the TQs!

 

[Photon440]

I just can't fathom a Quadrajet on a Mopar. True, when right, just like a Thermoquad, they are excellent carbs however I couldn't put Thermoquad on a chevy either. They just don't go together.

Mopar used Quadrajets, just like Chevy trucks used 833 transmissions. The best running carb I had on my 440 was a Quadrajet.

 

[GTX JOHN]

Some Fords like 460s had Thermoquads also

 

[4vnut]

Mopar used Quadrajets, just like Chevy trucks used 833 transmissions. The best running carb I had on my 440 was a Quadrajet.

Yes they did and they performed well in those applications.
Dad had a 75 454 Chevy pickup with a guzzling Holley spreadbore on it. I had rebuilt a Quad for it, installed it, tuned it and got from 9mpg with the Holley to 12-13 mpg with the Quad. Throttle response was awesome too. Great carb.

 

[Geoff 2]

800 TQs were used here on 302 & 351 Fords.

A TQ is a QJ on steroids.

 

[Photon440]

Not to mention that Ford used the Quadrajet on the 1971 429 Cobra Jet.

 

[440 4 speed]

1985 B300 360 4 bbl, had a Vanguard camper conversion. Quadrajet. Bought it in January 2009. 72000 kilometers. Drove to Galveston. Pig on fuel, no performance. 6-9 miles per imperial gallon. Took it to one of the better shops that do carbs. Could get 9-10 miles per gallon, still not much for performance. Put a 1971 340 Thermoquad on it. It had been on the shelf for years. There is one hill about 100 miles away that I had to put the trans in 2ND to maintain speed with Quadrajet. After we put the Thermo on I can actually go up the hill in drive with no problems. Have gotten as high as 16 miles per gallon. One drawback is, manifold doesn’t have well for a choke and I haven’t put a manual choke on.

 

[old guys rule]

With the helpful advice and encouragement of you guys, repaired ( fuel bowl leak) my thermoquad, thanks again to all.
But if it acts up think I ready for something brand new. Do not want to change the stock intake, which is a spread bore.
Looking for something that will bolt right up and reliable, nothing exotic or super high performance, really just plain vanilla. What do you think?
Thanks

Holly Made a couple of good spread bores. Don't know when they went out of production but they can be found. The 650 is a vacuum secondary and the 800 is mechanical, depends on how much you need. Obviously for the street the vacuum secondary 650 would be best. I've seen guys who claim the 650 runs better than a 750 even on a 440.

 

[old guys rule]

With the helpful advice and encouragement of you guys, repaired ( fuel bowl leak) my thermoquad, thanks again to all.
But if it acts up think I ready for something brand new. Do not want to change the stock intake, which is a spread bore.
Looking for something that will bolt right up and reliable, nothing exotic or super high performance, really just plain vanilla. What do you think?
Thanks

Just had a thought. I have a 800 CFM quadrajet, the ones they only put on the big block Oldsmobile motors. All the rest of the quadra Jets were 750 CFM. Let me know if you are interested.

 

[RJRENTON]

Just had a thought. I have a 800 CFM quadrajet, the ones they only put on the big block Oldsmobile motors. All the rest of the quadra Jets were 750 CFM. Let me know if you are interested.

How about a Holley 4175 650 CFM spread bore, vacuum secondary carb.....should fit the manifold....you'll need to adapt the fuel line and linkage......every one wants to over carb with an 800CFM Edelbrock AVS2 with a stack of adapter plates..?..bigger is not necessarily better.....
BOB RENTON

 

[Photon440]

Just had a thought. I have a 800 CFM quadrajet, the ones they only put on the big block Oldsmobile motors. All the rest of the quadra Jets were 750 CFM. Let me know if you are interested.

1971-1974 Buick and 1971 Pontiac 455s used the 800 CFM, I didn't know about Olds as well. They took different approaches; Pontiac removed the outer velocity boosters to increase airflow while Buick enlarged the primary bore in the main body.