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General TR Adjusting Carb Mixture for Seasonality

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RJS

RJS

Jedi Warrior
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Hi All

I live in CT and wondering if anyone adjusts their carb mixture for seasonality (or even the use of "winter" blend gasoline)? I was thinking perhaps the following:
  • Cooler Weather
    • one flat richer
    • i.e. before June1st, aft Oct 1st when temps <60*F
  • Warmer Weather
    • one flat leaner
    • i.e. June 1st to Oct 1st when temps >60*F
Silly or make sense? I've owned my TR4A for a long time and never really thought about it - just "set it and forget it".

Bob
 
With SUs I have never altered them once set. That included living in Colorado with the TR3A as my only transportation. And now California with temps at 100. It gets hotter than that and the car runs well but I don't without some A/C.
Charley
 
I've never come across anyone who advocated doing that with a non-British car, so why would you think that it's a good idea for a TR? A properly tuned carb will work just as well in warm or cold weather. Starting is a whole different situation, but that's why carbs have chokes or enrichment devices.
 
Just takes longer to get up to full operating temperature. Carbs are set for this temp. No need to change.
May need to run it on choke a bit longer
 
:iagree: This.
 
The SU carbs are a variable venturi ,and work well once set. Extreme altitude changes can make them too rich
however due to thinner air. Had to lean 2 flats last time up at Breckenridge Co. 9600 Ft. Had a blast there!!
Mad dog
 
Thanks All,
Classic me, overthinking things. Will stay the course as I have done for the last 24 years and "set & forget".

Hope everyone is having a nice Thanksgiving W/E

Bob
 
+1, I have never bothered to change anything seasonally, but it is a good thought. I think I just accept a slightly "off" mixture that averages the seasons?!?
 
When I drove my British cars year round I did this. Mostly because it would take forever for the car to warm up, idle properly in the winter.

I suppose from an engineering standpoint proper mixture is the proper mixture, but from a day to day live with aspect on an old carbureted car it seemed to make driveability better.

Cars always seemed to run best when ambient was 40-60 degrees, cars didn't really like extreme hot or cold.
 
I owned a Fiat 124 sedan in the late 70’s.
This car had a winter/summer setting on the air filter. Rotating the air filter housing would change the air intake from ambient outside air to warmer air coming off the manifold.
 
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