Pardon my ignorance: why is the 7M-GE so much less efficient?

[T-Supra]

Originally Posted by finaltable

The 3.0 V-6 in the '07 Honda Accord make 244 HP, 211 ft-lbs of torque and gets 21/30 MPG. The 3.0 7M-GE makes 200 HP, ~190 ft-lbs of torque and does about 18/23 MPG. I understand that the 7M has a longer crankshaft being a straight engine instead of a V but this doesn't seem to me to be enough of a difference to make such a disparity between the two.

Can someone shed some light on this for me?

(I'd like to point out that I am aware there is a roughly two decade difference in the technology of these engines. Were we just that much less knowledgable about what could be done with an engine in 1987? It just seems to me that given that the Porsche 959 came out around that time we (as people in general) couldn't be THAT primitive compared to today.)

Well, I for one understand that your just asking a simple question and your not trying to bash a Supra... I gonna give my 2 cents and I dont even own one...

20 years of development in engine technology has to play a big part in this... Compare a ECU from 1987 to 2007, theres more brains in 2 chips from an 07 one to the whole Supra ECU... Inector sizes will play a role in MPG, compression ratio will, engine internals will, timing will, gearing will, vehicle weight will etc... Lots of things to look at.

Just for the record, I have a 1971 Datsun 240Z, 2.4L I6 SOHC with twin 46mm side draft SU carbs, a 4 speed (no overdrive), 3.54 gears, and it gets 24mpg highway... the car only weighs 2300lbs, but it just goes to show anything can affect MPG.