SWAP D16Y8 for a D15B
 

Hi Guys,

so I bought a replacement engine for my blown motor and I'm just wondering if any mods are required to install a D15B VTEC in my 99 Civic si. The D15B is coming from a 96-00 civic so it is already OBD2... Anything else that needs modifications?

Thanks for your help!

Should be just plug and play for everything as far as I know...

Straight bolt-up. Except the y8 ECU won't be ideal for the d15b motor. You will need to convert to OBD1 and get the proper basemap.

Awesome, thanks for the replies! Glad to6 hear its a direct swap for the most part.

Only dilemma now is I need to purchase timing belt/water pump... Is it the same part numbers as required for a D16Y8 or are they totally different??

Thanks!

Just an update, my search on many forums confirms that the timing belt and water pump used on the D15B is that of the 92-95 Civic VX.

Thanks Chris. What do you mean by get the proper basemap? :confused:
Difficult to convert to OBD1?

All you ned is an OBDII to OBDI conversion harness.

By basemap he means the programing on the ecu (the fuel and ignition maps, etc...). It must be tuned to the specific engine you're running to get the most of your engine and keep it running safe and reliable.

What benefit would I get by converting to a OBD1...isn't that like going backwards?? If the car is already OBD2 and so is the engine (As it came out of a 96-00) I don't understand why I would be doing that??? Sorry I don't know much in terms of the engine technical aspects.

Thanks for the help!

If the engine you are swapping in is OBDII then yes, you should be able to plug in the stock OBDII ecu that comes with that d15b.

If you didn't, or don't have the OBDII ecu with that d15b, then you'd have to use a conversion harness and use a chipped ODBI ecu with the proper tune programed onto it for that particular engine.

The engine is OBD2..... I just spoke with the shop, the engine didn't come with the ecu.....he said you gotta use your stock ecu.....hmmmm, so I have a D15B from a 96-00 civic from Japan and I have a 99 civic si with a stock D16y8.... so to confirm:

1) I need to buy an ecu made for this engine and that is it, plug it in and I'm good to go, seeing that both engine and car is already obd2?

If you can find the right ecu (OBDII d15b ecu) then you should be able to plug-and-play. If not, you'll have to do the alternative, which we already mentioned...

Little confusing eh...lol.

Hahahaha, a little confusing??? LOL... No I think I'm getting the hang of it.... so now i get it....If I can't find the OBD2 ECU alternatively I get the OBD 2 to OBD1 harness and purchase a D15B OBD1 ECU which I think are a lot more common..............

Thanks a million for the help

Doing some more research, looks like the motor I bought is the 3-stage D15B VTEC..... and I think I'm going to have a hell of a time finding an ecu for it...dam it..

Not quite... you can't run an OBDII engine with an OBDI conversion harness on a stock, unchipped OBDI ecu. You must, run a CHIPPED OBDI ecu, which is easily tuneable via software on a computer (as OBDII ecu's cannot be tuned/reprogrammed in the same manor) with the conversion harness on an OBDII engine.

So, if you can't find a stock D15B OBDII ecu, then you must run a chipped OBDI ecu (via conversion harness) with a pre-loaded base map tune for a stock d15b. Not a stock OBDI D15B ecu.

It's very confusing, and I often get confused myself...lol.

This is actually one of the easiest, cheapest and effective ways of tuning B or D-series honda engines that are both stock or heavily modified. As a bonus, by going this route, your engine will already be setup to be re-tuned in the future, should you decided to do more drastic modifications.

I suggest you contact Zeeman (Andrew) at Hivelocity tuning (can find them in the tcc vendors section). He can help you out in this department and explain it a lot better then I can.

Good luck and hope your swap goes smoothly. :)

Thanks for the help.

Here's the deal with the ECU business in terms of why your motor didn't come with one. This isn't 100% factual as far as I'm concerned because this is only what I've heard from JDM importers when I was doing this exact swap. Those motors are usually in automatic cars, with automatic ECUs, so they are pretty much 'useless' by us.

There are a lot of people running the stock D16Y8 ECU with their D15B, but it's not advisable. If Honda's engineers thought it was okay to do so, they wouldn't have developed a different map for the D15B. Run your motor with its matching map and you'll avoid potential problems.

In terms of the swap itself, everything is 100% plug and play except the ECU issue as mentioned above. I personally would use your Y8 intake manifold as it flows a lot better than the stock D15B one. It made a very big difference on my motor.

You'll notice the VTEC solenoid is different (has two solenoids). Use your Y8 one.

I loved my D15B, it responded very well to an intake and a header. I was using zeeman's P08 map with VTEC set to 4800rpm to compensate for my DX tranny with its horrible gearing. It was great. Get yourself a P28 and have it chipped with zeeman's map. Also get the conversion harness. Having a P28 is a good thing because you can get tuned and never have to change your ECU, only the chip inside. You can use the P28 to run B series motors as well (in case you ever do a B swap). Another option is getting the conversion harness and a P08 ECU. I HAVE seen a couple for sale before. PM 'Pistol Pete' he might still have one.

Are you serious dude, I can just put the Y8 solenoid and that will resolve the whole 2 solenoid issue??? Cause I've been going crazy researching and found that it was next to impossible to get the correct chip 37820-P2J-003 as that chip for a manual tranny 3 stage vtec didn't exist in Japan and only in places like Singapore.............

I can get Zeeman to tune a p28 as u suggested, but I was stressing cause I did speak to him and he told me the only option to get this 3-stage vtec motor to work properly is to get that specific chip since it was programmed for 2 vtec solenoids.....I didn't tell him that I had a Y8 that I could use for parts....man, I hope this works out, I was just thinking I would have to get into an argument with the jdm motor shop to try to get them to exchange motors for a D15B with a single solenoid....

Thanks a million for this very valuable info...let me know if I got it right...

Before I guide you in the wrong direction, let me make sure of something...the VTEC solenoid you have is like this......?
Attachment 27328

If so, then yes, you can just use your Y8 solenoid and not bother with the wiring for 2 solenoids. It CAN be done, but its a lot more complicated than just re-re a different unit.

Does your intake manifold have an EGR valve on it? If so, then the motor probably came from an automatic car, so you'd have to put your Y8 manifold on anyway. Do it cuz it really helps with the power.

yup that is it, the dual vtec solenoid....Glad to hear man, I was doing some more research and I found someone who swapped it and it bolted right on but his car wouldn't accelerate past 4500 rpm....hmm, it would make sense though that it should work.

I'm not 100% on the EGR, I have to go take a look at the motor again but I will get him to swap the manifold on the car. I'm assuming it has the EGR since the motor came from Japan and from what I know now, they only came in auto there.

So have you actually done one of these yourself successfully and it worked out???....I tried anyways to talk to the engine shop and as expected he gave me his bs that I should know what I'm buying when I picked it up....he's willing to take it back less a 20% restocking fee!!!! I don't think its worth it....

Anything else I need to do for the swap to work?

Thanks

I had this motor put in my coupe couple of years ago. I replaced the dual vtec solenoid to the one, changed the intake manifold to the D16y8 and used the tranny from the D16y8 as well. I also used the D16y8 ecu too, the main problem i had with this motor would be no power from idle all the way to 5500rpm. Thats when the vtec kicked in.

Basically, the 3 stage vtec works as 3 steps. From idle to 2500rpm only 12 valves are working, than from 2500rpm to 5500rpm the 1st solenoid engages and all 16 valves work, than at 5500rpm till 7600rpm the 2nd solenoid activates and you get the VTEC. lol So, from using the single vtec solenoid, you are missing the 2nd stage which is 2500rpm-5500rpm. Thats why when i had this set up done, my car didnt have balls and you can hear the vtec crossover like a bseries. On gas, i was getting 650km to the tank but you will get frustrated and try to beat the **** out of it because simply.......................it just doesnt move. lol

This motor is like the vtec-e, its just a gas saving engine. They did make this motor in manual but the ecu is really hard to find. For OBD2a, look for P2J-003, and for OBD2b you need P2J-J11.