Out with the old TQ, in with the new TQ

[billschroeder5842]

I putting a "new" rebuilt TQ on my 400 this afternoon.

My old one was starting to leak around the gaskets coupled with a bit of backfire on hard acceleration (I do know this is a smogged 75, so "hard acceleration" is relative) and general lack of performance.

What else should I look for?

Any common TQ swap problems that I should be aware of?

I'm going to keep things stock so "super tuning" is not necessary.

Thanks!

[1973rallye]

Hope you have better luck than me. My original stock one had a warped bowl. My new one from summit, we couldn't get the secondaries to open. I finally broke down and installed a demon thermoquad lookalike. Very happy with it. We took the car to Minneapolis in October for a 1000 mile round trip. It ran beautifully.

[billschroeder5842]

I hope my luck is better than yours!

My only consolation is that the new one has GOT to be better than the old. The old one idles great but backfires on acceleration and the secondary's only open partially after max adjustment.

Fingers crossed!

[Nacho-RT74]

My new one from summit, we couldn't get the secondaries to open. 

did you check the choke link adjustment? this link also makes work the secondaries once engine is warm, making the counterweight lever link the primaries and secondaries work together when they must... not so hard to do.

Choke rod makes to engage the fast iddler cam. This fast iddler cam lever is counterweither... once is on position after warm, it gets a tab on rear area which push to another lever to catch the secondaries shaft and make them open. If the counterweight lever and rear tabs are not in position, the link lever won't catch ever the secondaries shaft system

http://www.imperialclub.com/~imperialclub/Articles/ThermoQuad/index.htm

[Nacho-RT74]

its MANDATORY make MOSTLY of the TQ adjustments in order ( there are some exceptions which allows you make one independent from the others ) but check on page 29, secondary throttle lever pickup. Thats the tab which makes the rear throttle link being linked with fronts... but choke systema allong with some other needs to be adjusted first

[billschroeder5842]

Thanks-I take a look.

I ended up putting on another carb--the first one was seriously jacked up. The second seems much better; I drove to work today.

I now need to do some tuning. I have an ever so slight stumble on take off between 800-1100. That might be a timing (I'm at 12-14 currently) and some rich/lean issues. Maybe a accelerator pump shot?

Thanks!