MTFCA Forum

How many of you have run or are now running a Simons type carburator?
That includes the "Wizzard", "duplex" or any other nameplate variation.
What is/was your experience?
Happy?
How do you rate/compare the performance to other carbs?

Curious minds want to know.
Thanks - John

Wizard carbs were sold by Western Auto. Those you mentioned are all the same. I don’t see how they’ve legally flourished since they’re basically a NH Straight Thru knock off. I run a Simmons and am very happy with it. They’ll all suck much more gas but performance is maximized with an aluminum hi volume manifold. Also run U&J updrafts on 2 runabouts. They’re better than any of the straight thrus.

I’ve ran a Simmons almost exclusively for the last 4 years on my 25 Touring. It starts easily and has a low idle. I think it has pretty even power across most speeds. Acceleration is good. I find it pulls hills better than the swayback NH that I use as a backup. Around town and in the hills I get around 16 MPG but that jumps to 20-22 MPG when we’re on open, flat roads. Most parts are interchangeable with the NH, except the Simmons’ mixture needle is significantly shorter.

There are a couple things to watch out for with them, though. They are VERY easy to flood when starting. I never give it more than a couple priming cranks when starting cold. The flapper behind the choke butterfly is what makes it work like it’s supposed to… sort of like an automatic choke and enriches the mix at lower RPM. It won’t idle correctly without it and it must freely move with increased airflow. There is also a preheater coil on the throttle side. I removed mine and plugged the hole. The preheater just sounds dangerous and it’s just another spot to introduce a vacuum leak. I’ve also noticed that if you yank the throttle open, it will hesitate, but you can quickly open it up with a smooth motion.

I have been running a Wizard for the last 20 years and have no complaints or problems at all. It is definitely more thirsty than the standard NH but aside from that it is a smooth running and easy starting carburetor. I definitely noticed a faster "pull" coming up to speed, and it seems to run smoother once we get there, compared to the standard swayback NH. I have run it with and without the flapper and only notice a difference when at slow idle; higher without the flapper and a bit finicky to get set right, and it has a bit of a "lope" (not a Model A gallop, but you can hear it) with the flapper, but easy enough to set.

I have also run an original NH Straight-Through (correct carburetor for the car) and the Wizard is a smoother running carburetor in my opinion, something just seems a bit "off" with the Straight-Through NH. It is a Russ Potter rebuild and has the Full-Flow needle and seat from Scott, but it just does not run as well as the Wizard. I installed one of the Full-Flow needle and seats into the Wizard and an aluminum manifold last year and I did notice an easier time when pulling up a hill.

I have never had a problem on cold or hot starts or icing up in humid weather, nor any flooding issues (except for a stuck float valve one time). I like the carburetor and have logged a lot of miles using it and I would not hesitate to recommend anyone in using it.