Walbro 340 vs. 340M...

[MeanBuicks]

What does the 'M' designate?

 

[Crazi]

I think the M means it gives higher pressure or operates better at higher pressure or something. This isn't accurate but lets say the 340 gives 60 GPH at 60psi. The 340M might give the same amount but where the 340 falls off at 75psi and only gives 45GPH, the 340M would give maybe 55GPH.

Those are numbers I pulled out of my a$$ but I think it works something like that.

 

[Mike Licht]

They are exactly the same pump the M means machined for the GM style strainer that goes on the bottom
Mike Licht