civtegra90

Now, I know this isnt exactly the most popular frankenstien motor,
but there are people who still want to try to make power from a SOHC.
I am currently building one of these ZC/VTEC motors for someone and I thought there may be people on this site in need of some tips, to learn from my mistakes, etc etc...

Im not saying this is the proper way to do this, but its how its getting done.

The car is a 97' civic si

My parts list:

-Complete D16Y8 motor (ours had blown rod bearings - the reason for the swap)
-complete JDM SOHC ZC motor
-set of new D15/D16 non-vtec head bolts (the Y8 bolts are too short)
-20 1mm thick hardened alloy washers similar size to stock head bolt washers
-tube of RTV gasket maker
-new crank seal for oil pump
-new head gasket
-new timing belt
-a nice arsenal of tools, including taps and a drill with nice sharp bits
(I dont remember the sizes, will look back up)

Step #1

Remove the Y8 from car, strip it of all usefull stuff:
-complete top end (will be left unmodified for our swap)
-knock sensor
-oil pump and pickup
-oil pan
-timing covers
-tranny
-driverside upper motor mount
-exhaust header

now, strip the ZC of all the similar parts.



Step #2

Now, start building up the ZC

-Install a new crank seal into the Y8 oil pump and put it in place of the ZC oil pump using lots of RTV and the stock bolts (torqued to 8 ft/lbs) and re-install the oil pickup.

-next, turn the motor onto its front and find a location near the top of the block for the knock sensor. We put ours into the oil return passage between cylinders 3 and 4, simply drill a hole slightly smaller than the tap, tap the hole and thread in the knock sensor. we used RTV on the threads to seal it and also installed spacers so that the sensor didnt thread in too far and block off the passage. now simply blow out the passage with compressed air to rid
it of metal shavings(i'd suggest wearing safety glasses for this).

-now that you've cleaned out the metal shavings, you can install the oil pan from the Y8. (the ZC oil pan will not fit with the Y8 oil pump.) The reason for using the Y8 oil pump is because of the crank sensor attached to it.

-At this time you may want to swap the canister where the PCV valve goes on the ZC block to the Y8 one, and install a new PCV valve.

-Next, install the Y8 top end onto the ZC. Put 2 extra washers onto each of the new non-vtec head bolts to make them just the right length. The Y8 bolts will only thread in about a half inch or so, not enough to be effectively strong (as this motor will probably produce 11 to 12:1 compression). Without the
washers, the longer bolts will bottom out in the block before fully tightening the head down fully (dont be fooled, without the washers, they will look and feel tight!). Torque the head bolts in 3 stages moving from inside out. first to 13 ft/lbs, than to 36 ft/lbs, and last to 49 ft/lbs. Then install the valve cover.

-Now with the head on, turn the cam gear to the "up" position and bring cyl. #1 to TDC and install the ZC timing belt, set the timing. (A new timing belt is a good idea), the Y8 belt is too short, dont use it. (The ZC belt is a little long for my tastes, but still fits snugly when tightened, use your own discretion here.

-At this time you can install the motor mount from the Y8 onto the ZC and install the Y8 lower timing cover (only 4 or 5 bolts will line up). We did not install the upper timing cover due to customer request.

-Now install the crank pulley and re-install all removed accessories.

-Take this time now to install the engine wiring harness cause it's a real pain to do it while the motor is in the car.

-You can now finish off all small unfinished things and install the motor into the car.


note:

I would suggest running a high octane fuel and/or retarding the timing a bit to avoid detonation due to the high compression.


I hope this has been helpful too you


The intention of this article is to give the reader an idea of what is involved in changing their engine. It is by no means a guide or a complete set of instructions on how to complete an engine change. The author takes no responsibility for damage or loss as a result of someone attempting a project like this. Things of this nature are best left to experienced people with
the equipment and knowledge to do the job.

meaneg6

very good info...u're thread inspired my friend to build a "mini me" swap for his civic