JDM B16A swap MPG success

[Johnny Impossible]

I have a JDM B16A I swapped into a 2000 civic coupe EX, which at that time had 48,000 miles on it according to hmotorsonline. I initially was getting 24MPG. I noticed that it always took a while to warm up. I pulled out the thermostat and noticed it was stuck open ( I suspected this of course). I replaced it and my fuel economy instantly improved to 29MPG.. around 75% city driving. I of course would step on it occasionally getting into the VTEC RPM range.

I've since changed my driving habits to see what I could squeeze out of this engine. By simply keeping the RPM's under 2,000 and getting to 5th gear as fast as comfortably possible and at times skipping gears... and coasting out of gear, I have been able to get at or above 36MPG consistently in warmer weather. I never turn off the engine to get this MPG. That's actually impressive MPG for a heavy civic that has extra weight because of a higher end stereo that's in it. Just so you don't think my math is sketchy..., I've been getting 400 miles per tank until the fuel light comes on and I end up squeezing about 11 gallons each time I fill up.

Now... I'm thinking of taking 5th gear out of my B16 tranny and replacing it with a 5th gear from an LS Tranny... I'm sure that longer gear will help on the road trips. It may be a while, but I'll post when I do this and have results.

I wonder if I did this swap in my 92 VX hatchback including the LS 5th gear... if I could get pretty close to the same MPG's I get with the D15Z1 that's in it? Right now that one gets 43 MPG consistently driving like the average person would. Hypermiling I get around 49 MPG. The car is like 600 or more pounds lighter. That would be an interesting experiment... Plus more fun to drive when accelerating.