78NOVA

my displacement is altered because of the head. plus the d15b2 ecu is dpfi when im mpfi. i have to either run a pm6/pr4/pr5 obd0 ecu unless i convert to odb1 which i dont intend to for now.

Bone1

crank/cam/igintion timing is all jacked up.

Cam timing is 1/2 tooth off

I believe the Y7 pulley has a different index point

yeah, all jacked up.

Meh, wait till it's warmer, maybe I can spend some time at Ollies

blackice90hb

buy and use my Z6 head and OBD1 conversion harness....im getting 350-400 to a tank...freeway doing 80+

78NOVA

if i had the cash i would. but i didnt intend on keeping the sohc to much longer, because im planning on a dohc zc swap. but if i can work something out maybe ill do it. at that id need an entire setup to get it to work, ecu, conversion harness, head etc.

Toysrme

stuck injector ftw. a narrowband o2 sensor won't read that rich to throw the injectors into 50% (or worse) mileage. atleast, not any setup i've ever personally encountered... which is afew thousand.

and if you swap injectors and its the same, throw a multi-meter on your map and tps

Adam Hopkins

Do you have any way of data logging?

I had a guy that came to me wanting to get his car tuned for gas mileage, I tuned his 91 civic and he went from 31 to 40 mpg on just the tune alone. Everything was going good until about 3 months later he calls me and says his mileage has went to ----. I asked him if there was any check engine lights and he said no. I told him to swing the car by and I would have a look at everything to see what was up.

Long story short his IAT sensor was giving his ecu a reading of -16 degree air when it was 40 degrees outside. The computer was throwing a ton of extra fuel in there to compensate for the lower intake charge.

The car would not throw a CEL because it was getting a reading that was acceptable to the ecu, Does that make sense?
Hope this helps, Adam

Inquisition

Stop throwing every damn D-series part together and thinking it will work together simply because they bolt up? There could be a lot of different issues because you decided to just throw a whole bunch of different parts together that may or may not play nicely together. If you wanted a simple engine that got decent fuel consumption, you should have just stuck with a typical D-series engine. Probably not what you want to hear but it is most likely the truth.

cloud

long *** thread.... Your just threwing parts at it. I probably wouldn't have replaced any of that ----.

but, it depends on what size tank you have. 8.9 or 11.9. obviously if you have the 11.9 200 is really bad.
I have the 8.9, I think my best take was maybe 350. but I drive for mileage (IHI turbo). I just got 300 out of a tank that I tuned with the first half.... I could see 200 if you rap it.

you need to get the lower timing cover on and adjust your ignition timing.

cloud

wow, that's seriously one of the smarter things I've heard on forums in awhile. never thought to check that in datalogging.

wait, wouldn't the o2 sensor compensate for that

78NOVA

thanks for being a dick you -------. and no, i did my research before i even did the head swap thank you. and no i didnt just throw parts together, i dont do something like that. all parts have been replaced or are new. the only thing i didnt do when swapping the head was a adjustable cam gear because i was told i wouldnt need one if i didnt go boost to pull timing. and it is a typical d series engine, i dont see nothing wrong with that head on top and a mpfi swap. maybe in your world you can do what you like. but dont be an ------- here and give nothing to help the situation. gtfo of my thread. everyone else is trying to help and so far everything is good.