Thermoquad on a 440 low comp engine

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thomaslk

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I have a TQ 9801S which is an aftermarket version with electrical choke and the small 1 3/8“ primaries (800 cfm rating ). What i digged up in the web so far was that usually all 440 were equipped with the bigger 1 1/2“ primaries (850 cfm). So i have the following questions:
Will the 9801S carb run nicely on a 1974 low comp engine ? Will the ootb jetting/rods be suitable? Tuning by center screw setting?
Is there any known TQ version with 1 1/2 primaries and electrical choke ?
Thx and Happy Wrenching in 2020
Thomas
 
None of the aftermarket TQ were 850 with electric choke. There were some Ford applications that were. The 460 was offered with the 850 and electric choke. If you can find one, it will need the Chrysler throttle adapter arm, I believe. The 800 will run fine more than likely as is.
 
Thx for the super quick answer. My assumption was even with the 800cfm rating it should not run worse than with the Edelbrock 650 AVS i have in use right now.
I guess a CH4B intake can be adopted to host the TQ secondaries?
Thomas
 
Fully Agree with RRR.

The beauty of Thermo Quads is the availability to tune pretty easy.
You will be fine with that low compression 440. Just spend your time tweaking the air door properly,
and adjusting the metering rods. You will be "popping wheelies" in no time.
 
Thx for the super quick answer. My assumption was even with the 800cfm rating it should not run worse than with the Edelbrock 650 AVS i have in use right now.
I guess a CH4B intake can be adopted to host the TQ secondaries?
Thomas

I'm not sure I would mod that intake. Ain't a lot of them left. I would choose the thinnest adapter I could find. I'm not an adapter fan, but I would be an even lesser fan of modding that intake.
 
I'm not sure I would mod that intake. Ain't a lot of them left. I would choose the thinnest adapter I could find. I'm not an adapter fan, but I would be an even lesser fan of modding that intake.
I may also use my Weiand 8009 for modification but then i have to provide an additional spread bore stud pattern in that intake as well. Seems to be enough meat in the flange for that and i have suitable helicoils. I also have a square/spread bore adapter but i think performancewhise they are not favourable because of the shape and i am also very limited in terms of hood clearance.
 
From my experience, the small primary TQ will feel a little down on power with a increase in throttle response, just not a ton of it. I had one on a low compression 400. (‘78) It really wasn’t bad at all. It was nicer on the primary side with the bigger TQ and the same at WOT.

I don’t think it’ll be perfect in its OOTB state rods and jets, so you may have to source a kit (really expensive) or search for other TQ’s to raid there rods and jets. Think before you buy.
 
The 1974 Ford 460 Thermoquad is the 800 cfm. Don't know why they used the small one on the 460, another thing they used their screw in fuel filter with a 1/4 hole. So the Ford guys never got to see how good their 460 could run with the 850 carb. I think most of the International models used the larger TQ's.
 
I have a IH carb. It is the larger unit.
 
The Ford 460 TQ and the 9800 series used the same baseplate, but the Ford machined the nipple for hot air assist on the choke. I was going to have one of my 9800's machined for the larger primaries, but there is not enough meat there to do so.
 
The Ford 460 TQ and the 9800 series used the same baseplate, but the Ford machined the nipple for hot air assist on the choke. I was going to have one of my 9800's machined for the larger primaries, but there is not enough meat there to do so.
Thx for the interesting info. BTW the Ford 460 produced about 200 ponies - so even with the 1 3/8" primaries the cfm rate might be more than sufficient.
@RRR: you are right - i will not modify the CH4B. So if i go the TQ route i will use the Weiand 8009.
Thomas
 
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