The D17 Swap Secret Formula

The D17 Swap Secret Formula

One6 Motorsports finally did it. A project that has been in the back of Mark's mind since 2002. 

It started with Mark's first Civic, a 92 EG Hatch Si. He had been modifying the D16 that was in the car for a while and was ready to try something new. The 01-05 Civic was out and it featured a big block D series engine, the D17A2. Higher displacement meant that there was some fun to be had. The problem, however, was that the EM2 had been released as an OBD2 car with a coil on plug ignition system and a cam shaft that did not have a notch for a distributor. So how would one go about swapping it into an EG? Engine management would be a challenge. Standalone ECU's were not even an option at the time. What mounts do you use? What do you do about the ignition system? Is it possible to make it happen while still using the stock D17 Cylinder head? These are just a few of many questions that needed answers. However, the major challenges were clear. 1: Find a way to mount the engine. 2: Find a way to make it run on a distributor so we can us an OBD1 Honda ECU. 3: Address the little things.

With some time passing and having not solved the puzzle, One6 moved onto many other "World's First(?)" projects. 

Dual throttle body RBC K-Swap EG that went 10's on OEM internals, B20V swapped EM2 running on K-Pro with an RBC, and the B16 bottom end with the LS cylinder head, etc..

This brings us to 2023. Mark walked past a JDM D17 cylinder head that had been sitting on a shelf in the shop collecting dust and had a thought. "Maybe the JDM cam shaft has a notch for a distributor..." 

He popped the cam plug out and, 2 decades later, there it was. The key. An OEM Honda D17 cam shaft that was notched for a distributor. The gears began turning again and before long, the engine was complete and in the test mule EG running and driving. 

So you want to know how to swap a D17A2 motor from an 01-05 Civic into an EG EK DC chassis and keep it running on an OBD1 ECU just like the rest of the SOHC engines of the golden era. Well here's the recipe...

You'll need an 01-05 Honda Civic Engine (D17A2) and a D Series trans with shifter linkage. Mark used a D16 trans and linkage. You can use any D16 clutch and flywheel.

For mounts, you can use Hasport D series engine mounts. Mark used the EG 3 bolt post mount from a D16. You'll need to trim the post mount portion of the alternator bracket to make room for the D16 post mount. You'll also need to mill .25" off the bottom of the driver side engine mount where it mates to the post mount in order for the engine to sit level. 

You'll now be able to bolt up the D17 alternator while using a D16 post mount. You'll have to extend the alternator wiring including the power wire coming from the fuse box. Mark chose to run the wiring straight over the valve cover so all the wiring was accessible during testing. 

Now we can talk about the distributor. Yes. Mark chose to make the D17 run using a dizzy. Here's why and how.
Why: he wanted this swap to be as OEM as possible. He also wanted this swap to have been accomplishable back in 2002 when he had the idea in the first place. We didn't have Digidizzy or standalone ECU's back then so this is a full OEM style swap.
How: he used the cam shaft from a JDM D17 cylinder head. There may be other OEM notched D17 cams out there, but we just happened to have this one readily available.
 Anyway, once the cam was installed, Mark modified an LS B18B dizzy by chopping off 2 of the bolt hole ears. Then he shaved a few areas of the distributor for clearance purposes. Also, you have to flip TDC inside the dizzy 180 degrees. Lastly, he "reshaped" the metal water crossover pipe on the D17 so that it would clear the dizzy and milled the aluminum cam cap on the D17 cylinder head so that the dizzy would sit flush (top dizzy bolt hole). You could use a washer or 2 as a spacer if you'd like, but this was an effort to make it look as factory as possible. So in summary, it is a modified LS dizzy that is bolted to the cylinder head with only one bolt. And yes. It is holding just fine. No leaks yet.
Another head-scratcher here is the header. This is a Skunk2 Alpha header for a D16. Not all the bolt holes line up so Mark used a BWR manifold flange as a spacer/adapter. Gaskets + copper spray has resulted in no leaks at all. You could also make a bar that goes across the flange and interfaces with the existing bolts to clamp the header to the flange adapter.
OKOKOK. The flange is cool, but that's not the largest hurdle with using a D16 header. The D16 header hits the D17 oil pan. Therefore, it will not fit without finding a way to make it not hit the oil pan. You could modify the header, but that's a pain. After a bit of testing, Mark found that you can use a D16Y8 oil pan and oil pickup to achieve header clearance. This was a huge W moment.
The radiator hoses were fairly straightforward. The upper hose is just a D16 upper hose and the lower hose is an RSX upper hose.

And finally, the intake manifold/intake system. All you need to do to make this D16 intake manifold fit on the D17 head is open up 2 of the holes in the intake manifold so that the bolt holes on the cylinder head have a way to receive the bolts. Then you just need to get a modified intake manifold gasket. We have one for sale on the site. Give us a call or send us a message if you have questions. 
And finally a pretty neat intake setup. This is our 3.5" AEM intake. It is base off of the AEM 21-412C Integra Type-R 3" Cold Air Intake. Ours is 3.5" in has built in adjustability so that it can fit most golden era engines. It will work for D, B, H, F series engines in EG EK DC engine bays. Must use the style manifold that is shown in these blog photos.
Well... It runs. And drives. And it's pretty fun! It's in the very early stages of development, but we should have this thing dialed in pretty soon. Also, I've left a little teaser below ;)

- John

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