I would like to share some information on selecting agood/tune-able ThermoQuad with the members/readers of this board. Too often thechoice is made to use a 'smogger' 1975-1984 carb on an engine that has had thesmog equipment disabled or on anengine that has several bolt-on mods; theseparticular carbs work well on the intended applications, but will give you pooridle quality and severe lean idle/off idle conditions and little or no'tuneability'. This is because the 1975 and up T.Q.' S have been redesigned toonly operate efficiently with an egr, egr timer delay and the fuel separator andon some modles, an altitude compensator and or an electric or vacuum'enrichment' solenoid.There are 3 catagories that T.Q.' S fallinto:1st is the Competition Series first run, 850 and 1,000 cfm versionswhich had 'press-in jets' circa 1969-1970; then the last run with 'screw-in'jets circa 1971-1974.
Both carbs shared in common the 1-1/2' od primarybutterflies & 2-1/4' od 2ndaries and the same metering rod tree as the oneyear only 1971 340T.Q.(1971-1974 C S and 1971 340 carbs used the same stylejetsand metering rods. The 850 C S had the double boosters while the 1,000cfm had just the inside 'small' booster and thus hadvery poor idlequalities.2nd is the 1971 Thermoquad only used on the 340 engines; itwas a decent carb, with 1-3/8' od primary butterflies & 2-1/4'2ndarybutterfly id's. It does not use the same jets/metering rods/piston as the1972-1984 carbs and is not as 'tuneable' and does not respond well to bolt onmods as the 1972-up carbs.3rd is the 1972-1974 carbs: these are the bestin as-is unalteredcondition even on engines with bolt-on mods and respondexcellently with simple rejetting and other simple mods. These carbs wereavailable in 800 and 850 cfm's and can be modified toover 1,000 cfm's. Theyare INCREDIBLY TUNEABLE/ADAPTABLE!The 1975-early 1978 carbs are alsoavailable in 800 and 850 cfm's and MUST HAVE mods done to the top plate/baseplate and accelerator pump nozzles and jeting when used on an enginewithout'smog' equipment or any engine with bolt-on mods; with these mods, these carbswill meet or exceed the performance/gas mileage of the 1972-1974 carbs and canalso be modified to flow 1,000+ cfm's! The same is true for the late 1978to1984 carbs(these do require a few more mods that the 1975-early 1978carbs)and these carbs will really perform incredibly well with theimplimentation of adjustable air bleeds.Then the SuperQuads were anaftermarket replacement for all year T.Q.' S from 1971-1984 and were sold from1978-1985; these were the last run for the T.Q.
And were 800 cfm's based on the1975 carbs and used a bolted on electric 12v choke just like the 1974 Ford 460T.Q. And the Australian Ford T.Q.' S.These carbs are the most 'tuneable'Carter carbs and you do not have to have 'special' tuning parts to goFAST!Any questions?, just ask! I can't believe that nobody here has any questionsyet!Let's bring this subject back up to the top.My firstquestion is, I want to put a TQ on my '88 Diplomat 318 police engine, to replacethe Quadrajet, which I have already replaced with an Edelbrock Performer withadapter plate. Runs OK, but part throttle performance is down and so is fuelmileage.What TQ number would be the one to look for? We have no tailpipeemissions check as yet, and most of the emissions stuff is non-operating. I haveeliminated the computer with a Mopar orange box kit, but have, as yet, stockexhaust with three converters.
This is for my wife for daily driving, not aperformance application.Thanks David for any help you cangive!:) By the way, Welcome to the site! I have not seen too many postsfrom you here, but you are generally regarded as the man to see for TQquestions! How is the development of a new Strip Kit coming?? What is the deal with bowl vents?
Carter Thermoquad Carburetor Parts
I got a coupleHolley 2 BBL 2210's from the yard today, from Vans, and they didn't have thebowl vent tube. One of them has the casting for it, would have to be drilled,etc. I was sure that both of these vans were newer than the 's that Ialready have, and they do have the bowl vent. Did they do away with that inlater years? List numbers are 6764 and 7188. Does anyone have a link for Holley2210 carbs that will tell me more about them? I plan on using them on 318engines.
Would the bushing be centered of I didn't drillanything? I went down to a hobby shop with throttle shaft in hand and picked asize that fit the shaft tightest without binding. The wall of the tubing ispretty thin.On the base, I just cleaned up the holees with a rolled up pieceof sandpaper. Didn't sand enough to change the ID. After doing this, the tubingfit snug, took some light tapping to get it in. The shaft feels like it fits thetubing the same as before but now the shaft doesn't jiggle around. There's nobinding at all.
Just smooth action.In an extreme case, something with athicker wall would probably be needed.As for the throttle blade screws, Iused loctite and staked them.Thanks for the replies! I'm still around!
I haven't posted here in a whileand will add some info about a new performance T.Q. Carb I have built.Mynew carb is a 'hybrid' race prepped T.Q. For a really mildly built 318. It usesmy race prepped mods and smoger carb technologyand will flow about 890cfm's.
It is based on the late 1978 to 1984800 cfm smoger carbs an is morespecifically a # 9391 1984' 318carb. It has a 'racy' look with all of mylatest technology including main and hi speed removeable bleeds for extratuneability and a hi tech look(the choke tower is milled off).I haveridden in and owned many low compression 340 powered cars and this 318 with thenew T.Q. Would have an excellent chance to run with a l.
It is thatgood!This carb is excellent for a stock 318 with a very mild cam/4 bblintake/dual exhuast and stock gears/transmission.This carb can back upit's radical looks with plenty of performanceand it gives the 318 aglass-smooth idle and really excellent cruzing manners. The performance just onthe primaries is sogood, it is hard to believe! The engine accelerates onthe primaryside so well you usually don't have to open all four barrels toaccelerate quickly!At wot, the engine really pulls strong to 5,000+rpm's and the exhaust note is a blast! At idle, the engine sounds like a hicompression 340 with a deep, smooth rumble.The engine starts just finecold or hot and the best thing is the gas mileage which is about 19 mpg athighway speeds of 60-65 mph. It is just a good T.Q, so don't throw away thoseold T.Q.' S;instead, go ahead and use it!
Yep, a Truck carb would be smog-free into the late70s. I've got one off a '77 B-300 Van on my '77 New Yorker and it definitlydidnt have any smog stuff, 440 in both, BTW.BUT, mine has a problem.Its ungawdly rich, you can really smell it. I've tried adjusting the mixturescrews and such, even put on a Blaster II coil. May need plugs, however.
When Iwas fiddlign with it yesterday, at first, it stumbled on the secondary openingand let out a nice cloud of black soot. It got better, however, but you couldsee raw gas get on that secondary air door after it opened, Normal?I'dlike to get this fixed, as my 440 has more umph with the TQ than it did with the600 Edelbrock. GSMAG:The last non smoger big block T.Q. Was#6545 and it has a top plate casting # 6-2146; if the top plate casting is6-2141or another #, it is a smoger carb assuming your carb is from a 1975-1977 truckor van. All van carbs after 1974 were smoger carbs regardless of enginesize.The only other acceptions for 440 trucks are #'s 9034/9035 for Feda/t, Calif-man trans; 9036 Calif a/t; 9096 Calif a/t.You will have togrind the excess glue off of the well covers and recoat as needed.MoparJamie, your carb is likely to rich due to the 2 special o-rings being dried upthat seal the primary pickup to the bowl; this is acommonproblem.I havefinally fired off Scott's 225 Hyper Pac with the ThermoQuad I build for it andMAN! This engine sure runs great and looks sooocool!!! We will hopefully getto drive it Monday.
I have finally got the T.Q. 'dialed-in' with the rightjetting/air bleed sizes and will post more infothen. V, you are exactly right that a T.Q. Tunes extremelywell on all three circuits and offers many performance and tuningadvantagesnot found or not easily accomplished on other 4 bbl carbs. I alsoagree that a T.Q. Is definately something different that really workswhenyou need it to.Snook, I'm glad to hear that the T.Q. Is working right;when I got it,it was way out of adjustment and I found nothing else wronginternally and I just simply put it back togther and bolted it to the testintake/engine and it fired off beautifully and all circuits were spot-on,DAVID.
DS,I have a TQ that I was told came off a 74 440.The upper casting has 6-4126 and the bottom cast shows 9022. Anyinfo?Thanks:usa:I think you transposed the #'s from the topplate; should be 6-2146 and is actually a 74' 360 truck carb. The Vaanth guidesays it is an 800 cfm when infact it is an 850 cfm as long as the primarybutterfly # is stamped 2-314 on the bottom side of each.I noticed yoursig and just thought I would add that I built a T.Q. For a slant six hop-up thatis a daily driver and belongs to a friend.
It is mounted to a Dutra Hyper packintake and really is bizzare to look at! Does anyone have any information on the ford truckthermoquad? Is it much different than the mopar applications? Desireable forperformance street use or not?Ford here in the US only used a T.Q. Forone year, 1974, on the 460 passenger cars. It was rated at 800 cfm's while thebig block and 74'-76' 360 hp Mopar and International Harvestor(except late78'-up) carbs were all 850 cfm carbs.The US Ford T.Q. Would have to be #6568 andis 'calibrated' for the 460 by jetting, emulsion/bleed id size and metering rodsize.
It would run ok on a mild small block. If you do have one of these carbs,I can make recomendations based on your engine specs, DAVID. Hey David,Give us an update on what yourworking on now in the way of TQ's.
The more I read the TQ seems the way to gofor a single carb. Installation.Barry and other loyal T.Q.
Lovers, I amcurrently working on 2 very different performance level T.Q.' One is my newrace T.Q. For about a 600+ hp stroker 360(now 408 cu in)and we hope to have thecar run in the 9.90's by the end of the race season.
This carb will flow as muchas 1,100+ cfm's.The 2nd carb is my new Twister carb, which is an 890 cfmrace build for very mildly cammed small block engines with a max of.460' liftand a max duration of 220 degrees.I have also begun to build NHRA/IHRAlegal T.Q. 's for Stock and Super Stock classes. This is a real challenge sincethe outward appearance has to be totally stock. Proof that beauty is not just onthe outside but what is on the inside really does count.I hope to haveBarry's carb back to him in a few days so he can go to the track and turn someheads by showing the competition his tail lights at the end of therun! There are 3 catagories that T.Q.' S fall into.I hopeto have Barry's carb back to him in a few days so he can go to the track andturn some heads by showing the competition his tail lights at the end of therun!David Cheves tells me he will be sending me today my STOCK/SUPER STOCKNHRA/IHRA legal - 1971 Thermoquad; with 1-3/8' od primary butterflies &2-1/4' 2ndary butterfly id's maxed to the limits and a second Thermoquad of 850cfm's with 1-1/2' od primary butterflies & 2-1/4' 2ndary butterfly id'smodified to 'full race' specs. To be used for testing at 5,800'.:)Thecar is ready and waiting, only need to get drivers side roll bar converted intoa 'swing bar'.
Thermo Quad For Sale
Have gone through the total car in updating per NHRA/IHRA -brakes to drive train, interior and exterior in 40 days. More rebuilding willstart in a few months when the snow starts to fly and everything (tracks) areshut down in area.:mmmmm. David Cheves tells me he will be sending me today mySTOCK/SUPER STOCK NHRA/IHRA legal - 1971 Thermoquad; with 1-3/8' od primarybutterflies & 2-1/4' 2ndary butterfly id's maxed to the limits and a secondThermoquad of 850 cfm's with 1-1/2' od primary butterflies & 2-1/4' 2ndarybutterfly id's modified to 'full race' specs.
To be used for testing at 5,800'.:) Received the carbs late yesterday according to the wife I was at work,figures, would have had one on by now. Will install the STOCK thermoquad thisweekend and make a few little changes to shifter 'delete' plate (an hours work).These aftermarket manufacturers build their products on the same moldand then adapt them to a dozen different model vehicles, shifters are the worst(same delete plate for everyone in some cases, just different length shiftingrods).
Have a TCI unit that either locks into 'high' or locks into 'park' butdoes not have enough throw to do both. Its either in one position and not quitein the other. By removing a little metal on the 'delete' plate (1/8') it now hasa long enough throw to work properly. At first I thought it was me doingsomething wrong until talking to a dozen guys and found a good percentage hadthe same problem and told me what to do to correct it.This corrected weare ready with 'Thermoquads Connection' carbs. To start testing at local strip.Finally back in the saddle again:plumcrazy.
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Carter Thermoquad Carburetor Diagram
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