Zenith Carb. replaces Tilly.

Chris H

Senior Member
When I received my '30 Tudor two years ago it came with a Tillotson carb. I have wanted to replace it with an original Zenith since day one, but other things had higher priority. I wish I had placed the carb. replacement higher on my list of priorities.

This weekend I replaced the tilly with a rebuilt Zenith and was amazed at the how much difference it made. I have rebuilt the tilly and I think that it was correct. No vacuum leaks and it seemed to have plenty of power. It idled OK and ran OK, or so I thought.

I put the Zenith on yesterday, and was amazed at how it improved things. It idles much more smoothly, and also feels like I have more power. It is a different car all together. Wow! Wish I had done it sooner.

It is going to take a little getting used to. It starts differently, and runs with different settings of the GAV and timing advance. Starting is a little different too. It is going to take a little getting used to, but all in all it is a great improement over the old tilly.

Chris
 
I know it's heresy, but my experience has been the exact opposite! My Tillotson runs way better than either of the two rebuilt Zeniths I've used.
 
I have a collection of Tilly's and Zeniths and have run both.

While I prefer the Zeniths for originality and aesthetic purposes, my experience is that performance and mileage has been similar for either carb that has been properly set-up.
 
I have ran both and found that the tilly had more power than the Zenith but the Zenith start and ran better at idle... Both the cars have Zeiths now!
 
Well, I guess I will never really know for sure, but I sure experimented a lot with the Tilly and it never did sound or run as good as the Zenith is right now. Of course, at the time, it sounded and ran alright, or so I thought.

Either way, I am extreemly pleased with the performance and the original look.

By the way, does anyone have any experience in running the K&B air filter on the Model A. I am giving one a try. So far so good. I thought I would give one a try for a few months and see if it causes any problems. It is easy enough to remove.
 
Well, I guess I will never really know for sure, but I sure experimented a lot with the Tilly and it never did sound or run as good as the Zenith is right now. Of course, at the time, it sounded and ran alright, or so I thought.

Either way, I am extreemly pleased with the performance and the original look.

By the way, does anyone have any experience in running the K&B air filter on the Model A. I am giving one a try. So far so good. I thought I would give one a try for a few months and see if it causes any problems. It is easy enough to remove.

Chris,

Chris Pelikan did a lot of research on many carb subjects and air filters is one of them:

http://www.modela.org/filtering_air_into_carb.html

Website is hosted by Bert's Model A:

Home page is:
http://www.modela.org
 
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I used a Tillotson model X on my coupe and a strip down through the seventies and eighties, The strip down still runs one. I bought two new Tillotson carbs from W&co. in 1970. The Tillotson performs as good as any in constant use. If removed and put on the shelf for a while, they usually don't perform well when reinstalled. After watching the Victor Duncan video, Carburetors and carbohydrates. I learned a few fine points about model A Zenith carbs. I now prefer the Zenith carbs, they don't warp and run lean like the Tillotson can. Here is a pic of the strip down, still running a tillotson model X.

I have found that besides restricting power and causing the plugs to run black and sooty, air filters cause way more problems than they solve when used on an up draft carburetor.
2058417-T600450.jpg
 
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Hi guys, I changed from the Tillotson to the Zenith and I would suggest that my car performs better with the Zenith. I guess the trick is exactly what everyone is saying and that is if they are set up correctly both perform equally. The Zenith certainly does not have any warping issues as we all know. There are many articles on how to ensure that you do have the correct jetting in the carbs as I believe to be most important, spend the timne, check the jets.
 
I have seen the video "'Carburetors and Carbohydrates' listed on some of the vendor sites but was not aware of what it was all about. I will have to check it out.

Regarding the air filter, my error: it was a K&N filter that I purchased. Just thought I would give it a try. I am aware that the filter can upset the balance of the A/F ratio in the carb. but wanted to see just how bad. I have been using K&N on other cars over the years and they have worked well for me. Will check out the other sites as suggested, Thanks.

Chris
 
The one that I used was an air maze. It seemed to make my carburetor noisey . It fell off a couple of times but the engine pan caught it. Some like them.
 
Back in the 60's when I was driving my stock "A" every day,I had both Carbs. I prefered the Tilly for everyday driving,and changed to the Z when going to club events. The Z would idle slower,and smoother,but the Tilly seemed to give better drivability. In 64 I started using two holly 94's,with other mods,on a 32 "B" engine,in the same car. Now I am using one Stromberg 97 on an Ansen manifold.
 
Im running a Tilly on the 30 pickup,starts easy and will "cut em off one at a time" Will poke,idle in 1rst. Stomp it and shes smooth and pulls good. I have been thru every passage in this carb and have no air leaks. Zenith...Same results,but sometimes drips. timing,points,valves,coil,are right on the money...AND I leave things alone!
Wick
 
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