So, my D16Z6 bottom end took a **** on me this weekend and the D15B8 was just laying in my garage so I'm throwing that motor back into the car for gas mileage and reliability. I'm using the Z6 tranny and IM. I was wondering if i can use the Z6's driveshaft with the D15B8 motor? I would use the Z6's head, but there was already some ticking valves prior to the dump my bottom end took. D15B8 will be slow I know, but I'm more worried about the gas mileage im getting out of my car...any help with this is greatly appreciated. I've searched and I always come up with mini-me swap guides and answers, but no D15B8 using Z6 driveshaft.

 

If you mean axles, then it doesn't matter. They are all interchangeable on that generation Civic (USDM anyway). Going a bit deeper into the thinking behind that, the driveshafts don't interact directly with the engine anyway. Since you're planning on using the Z6 transmission it's all going to be the same. Bolt engine in and you're good. Keep in mind that if you swap stuff off the B8 engine that there are a few other variances other than it being 8valve.

You can read this if you have time, it should explain the differences on the engine itself.

https://sites.google.com/site/24teng...h-16valve-head

 

What ecu will you be using?

 

The Z6 ecu if possible. Thanks for the link 24TEN...it explains why a lot of people swap out their D15B8. Idc though, I'd rather have the 36+ miles to the gallon, but still be zippy while accelerating...that's why I'd like to use the Z6 tranny and IM.

 

It'd be arguable that the manifold won't do much. Once you see the intake ports themselves on the 8valve head you'll understand why. I was averaging about 38mpg mixed driving before I converted my car to 16valve, now it's about 33mpg. The loss of 5mpg is welcome when you consider how much more drivable my car is now (basically a DX with Z6 gearing, Z6 intake/exhaust manifold, and an A6 camshaft). I'm considering going back to 8valve in the near future but I definitely hated the lack of power. I'd say your best bet is to use what you got and do a mini me conversion. Find a good set of lightweight wheels and low resistance tires and enjoy. If you're up to it, mix n match gears if possible.

 

My apologies brewcity for thread jacking:24Ten were you using a z6 head with the A6 camshaft and did you use a variable cam gear on it and where was it set for best performance.

 

^
It's all good man lol. I wanted to ask that too, if I ever hate how slow my set up is then I can go that same route. If the valves on the z6 head weren't bad then I would do the mini me swap, but the ticking of the valves is making me steer clear of using it.

 

I used a normal non-VTEC head, that's why I say it is basically a DX engine with those differences listed above. I forget what I set the cam gear at. You gotta remember that depending on the year of that camshaft you already have to compensate for 4.xx degrees that it'll be off from the start (I forget what the exact difference is maybe 4.75degrees?). I then just adjusted in small increments both ways but no more then 2 degrees off the new zero and just drove around. I don't remember what I set it at but I left it where the power came on soonest. I was mainly concerned with power down in the lower RPMs because it was for daily driving duties.

 

You're going to throw a check engine light with the P28 ECU. Also it's not going to get full MPF potential with that Z6 fuel and timing curves. Better to get the CX ECU, injectors and intake manifold if you're really in it for the MPGs.