No towing power, any one have this problem?

[Mertz]

Mtdave: I can help with the stumble. The things to check are the pump shot and the spring tension on the secondaries. Usually the spring is set from 3/4 turn to 7/8 turn from touch. I always adjust this with the carb off because it is hard to loosen the allen screw and hold the screw at the same time. You need to hold the screw or it will fly and you might break the spring. Never go over one full turn. On the pump shot make sure your rod is in the hole closest to the pump. It will give you a better shot. You need to look into the carb and make sure you get a good shot. You can call Cliff Ruggles at Cliff's Performance and he will help you get it right. I have spent a lot of time with him via emails and he has helped a lot. Also some qjets are set not to open all the way. Check and make sure yours does. Also make sure that your lockout is not keeping the secondaries from opening. They won't open if the choke is on. It has to be completely open to release the lock out. If the lockout is bypassed and the choke is not completely open it will get too much air and bog. Once you get the qjet tuned you won't ever have to adjust it again and it should perform like you have an EFI just make sure your fuel filter isn't plugged LOL.

dwragon: I pull a 6000lb trailer and have the same 4.10 rear end as mtdave. I have headers so there is no exhaust flap. The carb I am using was a very good carb according to Cliff. He set it up with an APT adjustment like the later carbs.