I did a mpfi swap on my civic and used a ps9 ecu, well I converted it (the ps9) to manual and did a tune up and I seem to be pulling about 32mpg and it still pulls hard at WOT. I'm wanting to chip it but I don't know what would be the best basemap to start with till I get a wideband 0² and chip burner. Is the 100cc difference in motors gonna make that much difference in the fuel map? I also don't want to lose any power so would i/e/h help air flow better and in turn help mileage?

 

I have used the pm8 its what it meant for it great mileage... Pm6 runs a little rich on the stock i/manifold, i think it needs more air? but you get 7200 rpm redline vs 5500 with the pm8.

 

I'd leave it alone until you get the other stuff to do a custom tune. It runs guns and give you 32mpg? sounds great!

 

Wow. Haha your D15B2 "pulls hard" does it?

I also have an MPFI swapped D15B2 in my '89 hatch with Si tranny even and the thing is STILL a dog. A bit quicker than the stock d15 and dx tranny but still an absolute dog by all accounts. It's like comparing a snail to a turtle and saying the turtle is "fast".

I really wish I hadn't even messed with it now because I went from 40+ MPG all day to barely 30 and after all mpg is what I got the car for. But, alas, it's all brand new (rebuilt everything) so I'll just leave it as is..

 

Thank you for your amazingly helpful information James89DX you have really made my life easier by helping with so much information on my project car..... it does pull a lot harder then it did with the dpfi sorry I don't own a dedicated 9 second drag car like you obviously do but this is the quickest civic I've owned