Tillotson carburetor

[Cockshutt Kid]

Good morning guy's. Do any of you have any information or knowlede on the Tillotson carburetors for the Model A's. The one that I am talking about is pot metal and has some sort of a power valve on the outbourd side. There are no numbers, just the name. The valve is actuated by the throttle linkage when it goes full travel. I assume that it give extra fuel on full acceleration? I have never seen a carb like this before and guess that it is an attempt at increased performance. Information or thoughts would be appreciated.

 

[Wick]

Set that one on a shelf and find one with the "x" on it. There's a lot of info on here about the Tilly's.

 

[Flathead]

That's the F1-B model. Not much info about it, there are new gaskets available, but I think that is all. I would like to know more about these myself, was it made before, after, or at the same time as the more popular model X or XF Tillotson? Were they any good? What problems, if any, did they have? I have rebuilt one and just put it on my A but have not driven enough to form any opinion yet. Someone out there must have some stories about these.

 

[Purdy Swoft]

I haven't seen much published info on the Tillotson F1B carb. Most say that it wasn't a successful design, I've got to wonder, I've seen lots of them on eBay. lots of people must have used them. I've got a few of them in my collection but have never run one of them . The F1B carbs were mentioned in the 3rd issue of the FAST hot for hot fours mag in 2004. in this article, Richard Lorenz says, Quote, The Tillotson F1B has slightly more flow restriction than the Tillotson X, partly because the internal flow passages are not as free of obstructions as the Tillotson X . The F1B also uses a thick throttle plate and shaft as in the Zenith 1 and Zenith 2 . unquote. Both the Tillotson X and F1B out flow the Zenith 1 and Zenith 2 in the flow tests in this article. The F1B does have provisions for enrichment at full throttle but is different than the model B or Simmons carbs in this area. I believe that the F1B came before the Tillotson X and XF carbs. The F1B is sort of a pot metal knock off of the Zenith carb with slight flow improvement and enrichment provision. The F1B has been said to be harder to clean the passages than the Zenith 1 and 2 carbs. The F1B was not sold by Ford as a replacement for the Zenith carbs. The Tillotson model XF was sold over the counter by Ford as a replacement after Zenith discontinued production of the Zenith A and B style coburetors.

 

[Flathead]

Thank-you Purdy for the excellent info. I have a box full of these and intend to get to know them better. I have no valid reason, they just appeal to me.

 

[Purdy Swoft]

Playing with carburetors has always been fun to me. I've got a few Marvel carbs that I'm cleaning up out in my home shop now. I think that the Marvel is the simplest carburetor that I have ever seen. Marvel carbs don't have performance enrichment provisions but still flows more air than the Zenith 1 and 2 according to the chart.