Anyone have any experience with mounting a Thermoquad on a 455? How would compare to a Quadrajet? It seems like it might be fun.
I had a 1000 CFM TQ on my 455 powered 64 Skylark. Trouble free for years and performed well. Best Et was 11.02 @ 124 MPH. I'm thinking of going to an 850 TQ on my 53 and dumping the Q-Jet. OK guys go easy on me I know you love your Q-Jets. :rant: :laugh: Bob H.
Actually the 1000 cfm TQ was THE carb of choice if you needed the airflow. Back in the day the only thing that flowed like that was a Dominator, and that wasn't even close to being a bolt-on! Devon
Thanks for the replies. I recently found a T-Q from a '77 truck with a 440. Will this work? It looked like a '72-'74 model. Any tips for set up? Anybody make or have parts for rebuild? I have been looking at the Demonsizzler site, he seems to be able to set these carbs up.
I would think the Demonsizzler site could steer you in the right direction and provide whatever you need. Bob H.
The Thermoquad most think of are the Competiton Series 1000cfm carb that works well. I have one on my car and when the engine was dynoed it had a high peak HP that the Holley 1000 but the Holley was stronger up to that point. The Thermoquad will get better mileage so I kept it since it will be a street car. If it a factory Thermoquad I would use a Q jet.
Can a factory TQ be reworked to a Competition Series level? The original 800cfm Q-Jet was not on my car when I bought it, so now I have 3 or 4 750cfm Q-Jets ranging from '71 to '79. I guess I am looking for an alternative, or maybe having a couple of carbs that I can swap on and off.
The thread is a bit old, but to answer to answer your question: Yes, but it will cost you, and may not work any better and a well tuned Q-Jet depending on how your engine / trans / rear is set-up and the weight of your car. scroll down on the website below..... http://www.thermoquads.com/
Thanks for the reply. I'll continue keep my eyes peeled for any thermoquads out there. Maybe I'll a 1000 cfm competition series! I'm also going to continue with the Q-jet as I'm getting some results, but as you'll read in a thread I'm starting in the Q-jet section, I can't seem to get the richness to go away.
I had a 1000 cfm competition series! on BBB on a Street car you want talk about a seat of the pants feel. I have a 1000 cfm competition series! carb it could be Purchased if anyone is interested they are not easy to find the 1000 cfm competition series! that is here is a picture
I had one on my car and loved it (850 cfm version). The primarys are smaller than a QJ but the secondaries are bigger than a QJ.
The Thermoquad is on. It's the 1000 CS listed above. I'm very happy with it. Thanks to this forum for connecting Buick folks together. I was worried about advice that this was too much carb for my mild 455, but I can see that'll work great! It definitely cleaned up the exhaust. Right now, I'm getting the bugs out. I'm getting a few backfires before the secondaries kick in and a low rpm surge. Seems lean, I guess. Gotta learn to adjust. Thanks, Gabe
The stock 850 (400/440 MOPAR) can be modified for more CFM. The outer ring on the primary venturi boosters can be cut out and the phenolic main body can be bored out to the dimension of the 1000 Competition Series. I got one running within .05 of a 1050 Dominator with great street manners.
The TQ's can be excellent high performance unit, no doubt about it. Parts selection for them isn't all that great, and they are complicated units. I much prefer setting them up for street/strip cars where we can get rid off all the choke and fast idle/cam linkage etc, as just about every part involved with the choke is an afterthought, and may require countless hours of bending parts to get it all working correctly. The TQ's became increasingly popular over the q-jet decades ago offering the same basic design with two needle/seat assemblies, two floats, two fuel bowls and more fuel capacity. There is also a very slight advantage in the design of the phenolic resin fuel bowl, as it keeps the fuel slightly cooler. With a well thought out fuel system, any real advantage over a q-jet quickly disappears. We have the smaller 750 cfm q-jets in service as fast as 9.30's at over 150mph. Users feed them with 250gph and larger pumps using 8 and/or 10AN lines/fittings. I've taken the larger q-jets and removed the outer booster rings from them, and made power and track numbers that rival the Dominator in back to back testing. Not trying to put a big black cloud over the TQ's, they are fine units, just not nearly as easy to obtain, and much more difficult to change the metering at the track, as the top has to come off for all jetting changes........Cliff
Cliff, Thanks for taking the time to post on this board / forum. Guys, Cliff R recently published a book on modifying the Q-Jet. It's a must if you're interested in Q-Jets. Regards, Tommy
??? Top has to come off the Qjet too for all jet changes! The qjet doesn't even have removeable secondary jets. The metering can be very easily changed via the primary rods on the TQ........ I used to drive to the track on one set of primary rods and then switch them. Changed the whole fuel curve. Ran lean and clean on the street and then fat enough for the track. Ran 10.40s at 127 driven to the track.....with an 850 modified to about 930cfm.
