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MGB Carburetion and MGB fuel economy.

Erica

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I understand that with a finely tuned engine the power to fuel consumption curve is pretty flat through the normal operating range of an internal combustion engine attached to a gearbox and axle -- why it is almost like a bunch of people with engineering degrees wearing white lab coats did it on purpose. But in the real world compromises are made which result in higher... never lower than the stoichiometric ideal... fuel consumption.
stoichiometric ratio graph.jpg


I have run my '77 -- equipped with a Blue Label overdrive, 25D4 (points with vac), dual HIF 4s, and separate '72 - '74.5 intake and exhaust manifolds -- through roughly 5,500 miles (all using low-butane E10 summer gas) and it has returned an aggregate 27 MPG. (About 29 MPG on the highway and 20 - 24 in small town stop and go traffic -- no traffic jams just stop signs, tractors, and low speed limits.)

I just took my (no overdrive) '79 -- equipped with a 25D4 (Optronic with vac), single HIF 44, basically a fabricated aftermarket copy of a Lynx intake manifold, and a '72 - '74.5 exhaust manifold -- out for a first drive and will chart it's fuel use.

Does anyone else have fuel use / economy statistics for other B-series engine setups?

Erica
 
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