Civic EG

I was wondering if it is possible to put the d15z1 vtec-e head on my jdm d15b. Other than wiring up vtec, what major stuff would I have to do? I'm looking to get as high mpg as I can while on a budget.

it would basicly be the same as any other mini me swap only you would be using an economy vtec head.... idk how much of a gain you would see.... but it is strait forward as the others....

what ecu would you use? Is this swap going into a vx or other model civic?
The ECU that runs the D15z1 also uses a wideband 5 wire o2, something to keep in mind for your swap.
Also you'll most likely need the intake & throttle body for the D15z1 head to achieve it's high MPG that the vx gets. The vx itself is lighter so it's going to get MPG easier than other civics.
But with a D15b bottom end, you will pretty much have a D15z1 but with stronger internals.

I have never messed with either of those motors, so I'll let someone with experience give all the details

teal_dx wrote:what ecu would you use? Is this swap going into a vx or other model civic?
The ECU that runs the D15z1 also uses a wideband 5 wire o2, something to keep in mind for your swap.
Also you'll most likely need the intake & throttle body for the D15z1 head to achieve it's high MPG that the vx gets. The vx itself is lighter so it's going to get MPG easier than other civics.
But with a D15b bottom end, you will pretty much have a D15z1 but with stronger internals.

I have never messed with either of those motors, so I'll let someone with experience give all the details

It will have the same internals as a b7 ... JDM D15B non-vtec and the USDM D15B7 are the same thing. Now if he was using the D15B vtec he'd have the stronger internals.

oops missed that in the thread title

Trang wrote:I was wondering if it is possible to put the d15z1 vtec-e head on my jdm d15b. Other than wiring up vtec, what major stuff would I have to do? I'm looking to get as high mpg as I can while on a budget.

For major stuff, get your hands on a VX/CX transmission ... with those long gears your MPG should increase substantially.

I would recommend against it. You'd pretty much need a donor VX to get all the little bits you need. The Z1 is very finicky.

There are two ECU's and two corresponding O2 sensors. CA and fed. Fed gets slightly better mileage, but uses the more expensive wideband O2 sensor which is complicated to wire up.

You'd need to wire up EGR and get the little controller box on the firewall.

You'd need to wire VTEC-E which is exactly the same as wiring VTEC.

Definitely need the VX trans including the flywheel.

You need a Z1 / Z6 distributor, intake pipe, and complete intake manifold. Exhaust manifold is not as critical and for this reason I'd recommend against swapping the VX ex manifold. It has the cat mounted right to the header so you'd need to do some custom welding to get it to fit your stock exhaust.

You're going to want the VX / Si front lip spoiler and the VX's rear diffuser.

That's all I can think of off the top of my head. You're better off getting some low rolling resistance tires and doing some heavy maintenance to the DX engine. It's a great motor capable of getting very close to the Z1's fuel economy.

I sold my VX fuel economy project and bought a stock 1997 Acura Integra GSR which gets me 36 mpg on the street (although it requires 91 octane). I'm quite satisfied with that and I love all the amenities that this car has that my VX 3 Stage VTEC project did not.

Wow, thanks for all the quick replies. I will look into finding a wrecked vx since it looks like I will need a lot of little stuff to transfer over. I am planning on having two cars, one for fun and one for unbelievable Prius A$$ kicking gas mileage.

The VX transmission should be a basic bolt on right? Also, a little off topic but a lightened flywheel, would that get a wee bit better gas mileage than a regular one?

Trang wrote:Wow, thanks for all the quick replies. I will look into finding a wrecked vx since it looks like I will need a lot of little stuff to transfer over. I am planning on having two cars, one for fun and one for unbelievable Prius A$$ kicking gas mileage.

The VX transmission should be a basic bolt on right? Also, a little off topic but a lightened flywheel, would that get a wee bit better gas mileage than a regular one?

Yes the vx tranny will bolt right up.

For the lightened flywheel get a stock one turned down. The 8.5lb aftermarket ones can be a bitch on the street. Mine's 12lbs (still 10lbs lighter than stock) and it can be a pain sometimes. The lightened flywheel allows your engine to spin up faster, and makes it not work quite as hard doing it. It will also allow you to hold it at lower revs more easily while cruising (my cruising sweet spot was about 2.7k before it would feel like it hated me and I needed to downshift, with my lightened one I can hold just fine around 2 or 2.2k). Your engine RPMs will drop more between shifts because of the lower inertia of the rotating assembly and it can be a little harder to get the car started from a dead stop.

Unles you are racing the really light ones probably aren't worth it.

suspendedHatch wrote:I would recommend against it. You'd pretty much need a donor VX to get all the little bits you need. The Z1 is very finicky.

There are two ECU's and two corresponding O2 sensors. CA and fed. Fed gets slightly better mileage, but uses the more expensive wideband O2 sensor which is complicated to wire up.

There is a third: A Canadian VX ECU will be the similar to the 49-state Federal ECU, minus the wiring for the ELD.

You'd need to wire up EGR and get the little controller box on the firewall.

You'd need to wire VTEC-E which is exactly the same as wiring VTEC.

Definitely need the VX trans including the flywheel.

You need a Z1 / Z6 distributor, intake pipe, and complete intake manifold. Exhaust manifold is not as critical and for this reason I'd recommend against swapping the VX ex manifold. It has the cat mounted right to the header so you'd need to do some custom welding to get it to fit your stock exhaust.

Not sure I agree with this - I bought a VX with a DX manifold, VX A-pipe, and DX B-pipe. Yeah, not great, but it all bolted together, as far as I can tell. I have since picked up a spare VX manifold to correct the problem. Guess I'll have two cat's though.

You're going to want the VX / Si front lip spoiler and the VX's rear diffuser.

That's all I can think of off the top of my head. You're better off getting some low rolling resistance tires and doing some heavy maintenance to the DX engine. It's a great motor capable of getting very close to the Z1's fuel economy.

Also, the VX's light A/C bracket, light alternator bracket, oil cooler, cluster, rims and even the trunk spare tire cover.