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  #1  
Old 05-06-2008, 12:34 AM
Chiphead Chiphead is offline
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Default Thermoquad tuning info?

So I have a TQ core, a 9103S. I believe it's from a '77 400. It appears to be all stock, and pretty gummed up. My buddy wants me to rebuild it to go on a '78 400. The engine will be stock except for a XE262 cam and removing the Lean burn crap.

Sending it out isn't in the budget, so I'm gonna build it for him. I've done a lot of Q-jets, but not a TQ. Where can I find tuning parts and rebuild kits? Any rebuild books out there? The throttle plates are corroded shut. How do I free them up?

Thanks again! Chiphead
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  #2  
Old 05-06-2008, 07:37 PM
valiant64 valiant64 is offline
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The rebuild kits should be available from your local parts house. Some parts such as metering rods, etc, may be harder to find. Check out Demon Sizzler's Thermoquad Connection website. He offers parts,& rebuild/tuning service. Also, there's quite a bit of info regarding p# applications, specs etc on this website in the Thermoquad guide. As far as stuck throttle shafts, you might try giving them a shot of good penetrating oil such as PB Blaster, AeroKroil, Sea Foam & such. Good luck!
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  #3  
Old 05-07-2008, 03:54 PM
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rumblefish360 rumblefish360 is offline
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I picked up T-Q rebuild kits from a local AP store. Though, jets and rods for a T-Q are not avaiable new, I can only recomend bending to length AFB rods to tune. It's approx. a 3/4 inch difference in length, longer.
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Old 05-07-2008, 11:28 PM
RacerHog RacerHog is offline
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I'd give Demon Sizzler a call before you did anything......

Also Find there T.Q. Tread here. It has lots of great info.

http://www.moparchat.com/forums/showthread.php?t=109005
I think this was it...Rob and Dave did a great job....


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  #5  
Old 05-08-2008, 12:42 AM
Chiphead Chiphead is offline
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Well, my adventure with the TQ didn't last long. The idle mixture screws were so corroded, they broke off in the throttle body when I tried to unscrew them. And no, I wasn't doing anything odd. Just tried to unscrew them and "SNAP". Good thing this carb was free.

So now I'm back to square 1. Where the heck am I gonna find a good TQ core, or a 9103S throttle body? How well do the Holley spreabore or the Q-jets work on a Mopar? Any issues with linkage?

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  #6  
Old 05-08-2008, 03:25 AM
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The Holley spread bores are not worth messing with. Pretty slugish compared to the square bore holleys. You can get a new TQ from your local Advance auto. Pick up several woth the money off of e bay. And next time when you have one droze up like that, get a gallon can of carb cleaner from the local parts store and soak the throttle plates in it. They also come with a parts tray in them so you can soak smaller parts as well.
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Old 05-08-2008, 09:09 AM
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rumblefish360 rumblefish360 is offline
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Thank RacerHog.

Demonsizlers site has a few T-Q's for sale. Junk yards, if it applies in your area, can have a few laying around. Choose an earlier year model for performance applications. They first came out in 1971 and were an air metered design. You should avoid these for use, but can turn in a decent penny for a restorer.

Also, one with larger primarys would be a bennifit.

DWC'S suggestion of Advanced auto requires a core. Which you have. But I don't know if they regulate the new carb to the core. As in direct model number swap only. It's worth a shot.
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  #8  
Old 05-08-2008, 07:25 PM
valiant64 valiant64 is offline
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The core charge is around $5-10. I wouldn't sweat it. Save your core for any reusable parts & buy the reman outright. Usually around $230 for a Holley reman'd Thermoquad.
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Old 05-08-2008, 11:56 PM
dodger1 dodger1 is offline
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I'll agree with the other respondents - hang onto the core (even if the throttle plate is toast) for parts, and go with demonsizzler for a proper replacement. If you can find other cores in your local j/y's grab them, chances are they'll be glad to get them off the shelf cheap. These carbs are getting pretty scarce now. They are not difficult to set up for a street engine, providing the bits and pieces are useable. If you find another core, I'd go with dwc's advice - separate the throttle body and soak it before dis-assembling it further. Any FSM from mid-70 to mid 80 will have servicing details.
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  #10  
Old 05-09-2008, 08:42 PM
Chiphead Chiphead is offline
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I was trying to not got into a big spiel about what this project is, but WTH.

A buddy has a '76 volare with a slant 6. 4-door grampa car the color of fried asparagus. He got a 400 B engine for a song. He's going to perform a shotgun wedding between the two, and I'm the minister. Like most newlyweds, the engine and the car are gonna get by on the cheap and live with momma until the engine proves it can get up in the morning and hold a job. Once the happy couple save some money, Bill the engine might take a vacation and start hotrodding, if Victoria the Volare approves.

This means stock intake, stock pistons, bare-bones ring and bearing job. Carburetion on the uuber-cheap. I wanted to put a $30 kit in the carb and have it ready. Looks like it's time for Plan 9 from outer space.

So, out of Holley, Q-jet or TQ, which is the easiest to get to work on a stock-ish engine with the factory throttle and tranny linkages?? I know Q-jet really well, I can get by on a Holley. The TQ looks like it'd make a good ashtray. Budget is $100 american pesos.

Are we having fun yet?
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  #11  
Old 05-09-2008, 08:44 PM
aarracer aarracer is offline
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The q jet is stock on some later 360's so you could go there cheap!
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  #12  
Old 05-09-2008, 08:46 PM
thatwasfunny thatwasfunny is offline
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The q jet also has a tiny fuel bowl.
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  #13  
Old 05-09-2008, 08:49 PM
thatwasfunny thatwasfunny is offline
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I have a friend that has a pile of good carb cores I will hook u up with what ever carb u want that he has and will sell.
u pay shipping and core price. Holley or T-Q. [to be non bias]
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  #14  
Old 05-09-2008, 08:50 PM
Chiphead Chiphead is offline
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You telling me Mopar don't have a decent fuel pump? The mechanical pump on my Pontiac can keep fuel in the Q-jet up to 6200 RPM.

But I'm running aftermarket linkages and intake and a 455 HO fuel pump.

My books show that the Holley spreadbore is rated for 650 CFM. There were mechanical and vacuum secondaries, but biggest I see is 650. Is that big enough for a mild-moderate 400 Mope?
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  #15  
Old 05-09-2008, 08:54 PM
thatwasfunny thatwasfunny is offline
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No actually mopar sb pumps for instance flow 5 1/2-6 psi and takes my small block 7000. I was just pointing out that in the over all scheme of things the Qjet is not as good as the therm-o-quad.
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  #16  
Old 05-09-2008, 09:01 PM
valiant64 valiant64 is offline
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After having worked on some quadrajets, I can say that they have their place. On a GM product! As far as the Thermoquad being a "dinosaur", ALL carburetors are old tech, Carters or Holleys, Rochesters or Strombergs etc. But in reality, Holley carbs ARE everywhere...just like Mustangs & Camaros are.lol. Holley really hasnt changed the overall design of their carbs that much over the last 30 some odd years, and they still work. So how can a Carter that was of the same era be all that much more archaic in design? I guess it all depends on what you prefer to run, and what your intentions are with a given car.
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  #17  
Old 05-09-2008, 09:04 PM
thatwasfunny thatwasfunny is offline
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Really you can run 650 no problem, especially if it's just getting by with mid hyd cam build. would it love 750 or so cfm dbl pumper? hell yea!

Adjust ability is what divides the the better/best carb.
Air bleeds idle/main, wide range of shooter size, variety of booster syles to optomize atomization, jet sizes, power valve ratings, CFM choices, vac or mech secondary initiation, center or side hung float bowls?

And we could be talking webers now humm.....

come on! if this don't convince then arf arf ! old dogs lol
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  #18  
Old 05-09-2008, 10:00 PM
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Quote:
Originally Posted by Chiphead View Post
My books show that the Holley spreadbore is rated for 650 CFM. There were mechanical and vacuum secondaries, but biggest I see is 650. Is that big enough for a mild-moderate 400 Mope?
The vac spread bore holley is a 600, the mech sec spread bore holley is a 650. Neither one will hold a candle to the TQ at a stock 800 or 850 cfm. The biggest difference is in the boosters that cover a larger rpm range over the qjunks.
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  #19  
Old 05-09-2008, 10:02 PM
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Originally Posted by thatwasfunny View Post
Really you can run 650 no problem, especially if it's just getting by with mid hyd cam build. would it love 750 or so cfm dbl pumper? hell yea!
A 650 is wayyy to small for a 400. It would really kill the top end hp and not help the low end at all either.
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  #20  
Old 05-09-2008, 10:05 PM
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Quote:
Originally Posted by Chiphead View Post
So, out of Holley, Q-jet or TQ, which is the easiest to get to work on a stock-ish engine with the factory throttle and tranny linkages?? I know Q-jet really well, I can get by on a Holley. The TQ looks like it'd make a good ashtray. Budget is $100 american pesos.

Are we having fun yet?
The TQ is the easiest to tune, or build than any holley or q jst, plus you don't need to buy a ton of parts to tune the thing with. And it's stock on that engine so there's no other car that can hook up to your stock linkage any better than the Tq's at least not without some work done to it. You can pick up a good Tq from e bay for less than a $100. Always having fun ... lol.
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  #21  
Old 05-09-2008, 10:36 PM
thatwasfunny thatwasfunny is offline
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Quote:
Originally Posted by dwc43 View Post
A 650 is wayyy to small for a 400. It would really kill the top end hp and not help the low end at all either.
Low end? What cfm carter carb came on 68 383?
Yea wait till you get the T-Q on there with it's booster that practically blocks the whole primary then the sewage pipe sized secondaries open with piss tubes hosing the fuel in,

Great performance.

Oh, but wait.. don't tell me... you'll adjust the air flap, right?

Oh yea,
Who wants cheap available parts so they can precisely tune their carb???
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  #22  
Old 05-09-2008, 10:54 PM
dodger1 dodger1 is offline
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If you are really looking to carburate this engine cheaply (stock throttle and k/d levers and linkage,) the TQ or a post 85 Mopar-spec QJ is about all you got to work with. Carter stopped making the TQ after 85, and the 86-89 M-body copcars had QJs, whereas Holley is still going, so all the naysayers are beating a dead horse on that subject. Again, I recommend you talk to Dave at Demonsizzler before tossing the rest of the carb. (I agree your throttle body is probably not worth repairing) If you're comfortable working with QJs, maybe that's the way to go, but you will need to modify a Mopar unit as they are sized for a 318 and are a smog carb. More $$$. I didn't mention going to a square-bore carb as that opens another can of worms (adapters and linkages again)
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Old 05-09-2008, 11:01 PM
dodger1 dodger1 is offline
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I guess in a perfect world, we would just trot out to our well-stocked garage, select a nice aftermarket manifold and carb, complete with correct Mopar levers and linkages, and bolt it all on. Some of you guys are NOT LISTENING! The man is trying to do a budget swap here, and he said he wanted to keep the carb part of the swap to a $100 budget.
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  #24  
Old 05-10-2008, 12:27 AM
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Quote:
Budget is $100 american pesos.
Since the budget is set, it kind of speaks of what you can do. Rebuild a carb. What ever carb you settle on, like said above, it doesn't know or care what it is on, just take the time and do it right.

Look around the J-yards and swap meets for a cheap carb. Used carbs can go as cheap as $20. I grabed a 4160 - 600 cfm Holley for that much and the rebuild kit was... I think I paid $35. Easy to do, it's up and running atop my duster now on a a days soaking and labor.

The T-Q or anyother carb should be just as simple to do.
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Old 05-10-2008, 10:20 AM
RacerHog RacerHog is offline
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I'm with you RunbleFish....
I needed a T.Q. for a Dodge Motorhome, Went down to the wrecking yard.
Found one laying in the dirt..... Carb cleaned it...installed it.....Drove it for three years.....And Sold it running like a top....
Get in the wrecking yard $ 2.00
And the carb cost me $40.00 With a warrinty

Hope you get your carb Fixed...... There not that hard to fix and run great.....
You can tell the people here who KNOWwhat there doing and the others who just replace parts, just throwing parts at the cars to fix them....

Good luck...keep us posted on how it comes out...

Bob
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Old 05-10-2008, 11:20 AM
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I've worked on them all, and they all have their place. When a carb is tuned right its a good carb. And a mild 400 doesn't need 750 800 cfm's. Most poeple don't cruise around at 6000 rpm. A 600 to 650 will run nice. I just rebuilt a 650 Holley double pumper an a friends mild 440. Yes its under carbed slightly, but still goes like hell, has great response, and he was happy. So find a good cheap carb to rebuild, as long as you know what yer doing it'll run fine.

good luck.
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  #27  
Old 05-10-2008, 11:37 AM
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BBDude, you make a good point many forget about. I think it was mentioned above before. But just because the engine displaces large dosen't mean it needs a large carb. A great example is when Chrysler used a small Carter AFB on the 440's.

A old freind of mine had a Chrysler Imperial, a 67 model IIRC that had the small Carter AFB on it. No secondary door model. I think it was at or around 600 cfm's.
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  #28  
Old 05-10-2008, 12:12 PM
thatwasfunny thatwasfunny is offline
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Exactly, I mean you can always get a lil more out of the bigger carb but does it or have to have it? no.
Really though you don't have to run 6000+ rpms to feel the benefit of the larger carb either. it's all tuning.
Restricter plate nascar=390cfm how many rpms?
This has been very productive and for the record no one started bashing T-Q until it was known that the core was pretty much toast, then some die hards wanted to get comparing carbs. Why ? it's like b&w tv to color tv, if your color blind of course you don't see/no the difference= in other words if you haven't tuned a great variety of combos mild to wild you won't come to appreciate the versatility of the holley.
Any one run .557 solid with T-Q's. I can.
BTW I can rebuild a holley faster than u can premature ejaculate. ha ha lol
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Old 05-10-2008, 12:16 PM
thatwasfunny thatwasfunny is offline
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Are any of you guy's gonna make fontana mopar shoot out may 24-25?
Love to see ya there, will pound some cold ones after the race.
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Old 05-10-2008, 09:26 PM
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Chiphead, you still with us? I wouldn't argue with 'fish and 'funny but having a square-bore pattern manifold makes for a hell of a lot more choices. The spreadbore that you have plus the $100 budget kind of restricts one to a rebuilt TQ. Have you found an acceptable solution yet?
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