thermoquad install

[leanburn]

i got my hands on a tq and would like to make sure i'm hooking it up right. all i have is a pvc, no vacuum advance. i assume i can just plug all the ports that i'm not useing just like a holley? can i remove the choke plate without affecting anything else?

[Bullitt-]

OE style mechanical choke?...taking the plate off won't hurt but you will need to fix the linkage in the down position like the choke coil is pulling down or you could have issues with the secondaries being disengaged. 

[Bullitt-]

I've had to free the squirter valve up to get the accelerator pump to work every time mine sits long enough for the fuel to evaporate...Take the squirter off & shoot some cleaner in the hole & make sure the brass valve is free. 

[leanburn]

i installed the carb today and i must say, way more low end response, no spitting, no sputtering, no surgeing, just smooth running. i haven't done a plug burn yet but that will be next. this carb has me very interested, is there any performance books foe these style carbs?
 now that i may play with this thing a bit i have a couple of questions. what is a purge port? what is this choke pull off i keep reading about.

[Bullitt-]

Choke pull off it a vacuum pod that pulls the choke open a smidgen as soon as the engine starts, it continues to exert on the choke linkage holding it as far open as possible.

The purge port is not found on the earliest production or some of the performance series models. It is on my '73 model & has a large vacuum hose that goes to the vapor canister.
On the top right side you just need to cap it. 
I've seen some publications listed but I doubt their in print any longer..this link give some basic tuning info http://www.thermoquads.com/page204.html

[leanburn]

thanks, that helps alot.

[leanburn]

are the mixture screws fuel screws or air? just wondering which way is richer and leaner.

[Chryco Psycho]

same as most carbs clockwise leans the mix

[Bullitt-]

Here's a good how to...using a holley but the procedure is the same
http://www.chevyhiperformance.com/howto/45638/index.html

I took the statement below from http://www.thermoquads.com/page204.html. I preset my idle speed screw for the transfer slots to be square prior to installing the carb.   Adjusted the mixture screws w/o messing with the speed screw, turned out good especially after Moparal helped me get the timing advanced enough, about 15-degrees at idle.

Idle transfer slots
Pay close attention to the idle transfer slots(rectangular)in the front of the primary bores of the base plate. When the carb is correct in cfm's and jetting, the slots will only show a square when the butterflies are in the normal idle postition. If the slot is a rather large exposed area, the carb will need the inital timing bumped up which will increase the idle speed and will allow the idle speed screw to be backed down, thus exposing less of the transfer slot. If the slot is less than a square, back off the inital timing and crank up the idle speed.

[Skunkworks Challenger]

I'm building a 440 and like the idea of a TQ on it.  I have one from my 340 but have no idea what cfm it is.  How do I determine the cfm of this TQ carb.  For my 440 I want 750 to 800.  PK

[Bullitt-]

I'm building a 440 and like the idea of a TQ on it.  I have one from my 340 but have no idea what cfm it is.  How do I determine the cfm of this TQ carb.  For my 440 I want 750 to 800.  PK

"1-3/8" bores are listed as 750-800 CFM and those with the 1-1/2" primary throttle bores are rated at 800-850 CFM. All TQs have the 2-1/4" diameter secondary "

Find the model off the base plate rear drivers side .... match the # to the list on this link...bore is key to cfm
http://www.carburetor.ca/Tech/Carter/tqguide-Vaanth.html

[leanburn]

i had to use an adapter plate since i have a square bore intake and i can see that having the proper intake would help alot but if i bought a spread bore intake would i have the same problem if i wanted to go back to a square bore?

[Bullitt-]

I see some of the dual plane manifolds will accept both
http://www.summitracing.com/parts/EDL-2101/
http://www.summitracing.com/parts/EDL-2191/

[Skunkworks Challenger]

Thanks Bullitt for the link to all that great TQ information.  I've not had a chance yet to determine which carb I have but will soon.  If my TQ is not big enough for my stock bore/stroke 440 I'm thinking of going with a 770 Holly.  Any opinion?

[Bullitt-]

Our resident guru will say 770 is kind of small for a 440, I'd say it depends on how your going to drive the car, strictly street or do you want to maximize your top end.