Weber Carb Conversion MPG Change?

[N-Dually]

Hi All,

I have been reading that a lot of you folks do the Weber carb conversions. Has anyone paid attention to the change (if any) in fuel mileage? Better or worse? Numbers would be great!

Thank you!

[bandytZ24]

Just put a Weber 38 on mine and its a great improvement, bout +4mpg, and mine was already getting 26mpg. Tuning is an important part of this process though, keep in mind this will work better if the engine is sound.

[fastboatman29212]

I suspect mpg will be better with a Weber. Most Webers go on a 720 when the stock Hitachi poops out. It's no surprise that a new Weber will get better mpg than a pooped out Hitachi that needs a rebuild. I have never seen someone get worse mpg with a Weber.

I plan to get my Hitachi carb tuned better now that I have done the rebuild and then I will report my mpg. In the end, I might buy a Weber if I can expect to see better mpg.

[PEZi]

I have never seen someone get worse mpg with a Weber.

Right here!

I went from a fully functioning Hitachi to a Weber 38DGES... the extra fuel it throws into the engine and the advanced timing to burn it all will of course give worse gas mileage... you can't expect better when you're throwing more fuel in.

[fastboatman29212]

Pezi,
Don't you think your setup is an exception to the rule? I mean you have yours set up for racing. What I meant was that the average Weber 32/36 should do as well or better than the stock Hitachi. I have to admit though, that I only think this because of threads I've read where people are getting >25mpg with a Weber.

[synack7350]

I'm running about 27mpg on my 32/36 that valve adjustment might have helped things along. The great thing is when you open up that 36

[N-Dually]

My Weber is now on. Running SO MUCH BETTER!!!

[PEZi]

Pezi,
Don't you think your setup is an exception to the rule? I mean you have yours set up for racing. What I meant was that the average Weber 32/36 should do as well or better than the stock Hitachi. I have to admit though, that I only think this because of threads I've read where people are getting >25mpg with a Weber.

Well.. yes and no. I don't see how a Weber 38 would ever get better mileage. But yes... a 32/36 will get as good or better in almost any situation.

[fastboatman29212]

My Weber is now on. Running SO MUCH BETTER!!!

You promised pix!

[N-Dually]

There are a couple in my build thread and a link to my blog that has many of them.