Running rich

[Member 10617]

For some reason, my TR3 runs best if it is running rich. The guys in shop who worked on the engine replaced my standard needles with rich (RH) needles to improve performance. And when I adjust the fuel/air mixture on the carbs, the car is happier when they are on the rich side. Can someone explain that to me? Could it be the chemical composition of modern fuels (even though I am using non-ethanol gas).

 

[Geo Hahn]

...the car is happier when they are on the rich side...

Which method are you using to determine that they are set rich?

 

[Member 10617]

George. I'm just noting how far down I have to turn the jet adjusting nut. Then I do the piston lifing routine to make sure there is no increase or failing.

 

[hondo402000]

I was told an engine makes the most power when the AF ratio is 13 to 1 air to fuel

best fuel economy with out damaging the engine 14.7 to 1

Hondo

 

[KVH]

I run mine with the adjustment nuts opened up about 12 flats. It's a bit rich, but it does run better that way. I've never been able to lean it up. If I do, the idle speed is too fast and I can't reduce it and keep the car timed as well. That's in part why I let it stay a bit rich.

 

[hondo402000]

As long as you dont have black smoke coming out of the tail pipe I dont see a problem, running too rich will wash the oil off the cylinder walls and wear your rings out prematurally

Hondo

 

[TomMull]

As long as you dont have black smoke coming out of the tail pipe I dont see a problem,

Hondo

And no fouling of plugs.
Tom