Mk2 1800RS (BP5A) swapped into '97NA

Hey all!

I haven't posted on this forum in quite awhile. Heck, I haven't been playing around with my Miata in years. Mostly, because I was bored and frustrated with it. The NA Miatas that were sold here in the Philippines in the 90’s are the low horsepower 1.6 versions: that's the 88hp 1.6.

I was constantly looking for ways to increase the engine's power. I tried supercharging with a Sebring unit, I wasn't too happy with that. Too many struggles with heat, detonation, and parasitic drag. I looked into installing a turbo but that never really pushed through. I had already installed an Adaptronic E420C in anticipation of the turbo. That was a huge debacle. The car was already suffering from myriad electronic gremlins and when I installed the ECU those electronic gremlins were further exacerbated.

The car ended up being sidelined for at least 5 years, rarely being driven. I hardly used it as it was no longer reliable. And moreover, the car ran rough as the ECU couldn't be tuned because of the electrical problems. The last straw was when the car started burning up coil packs. By this time, I was considering selling the car.

But a couple of months ago I found a front clip of a JDM NB in Quezon City which is about 40kms away from me. NB’s are rather few and far between in the Philippines as they were never sold here. As such, it’ very difficult to find NB motors or parts cars. This one that I found was from Japan and it was cut up in Japan to be brought here as a parts car.

Another miataphile (Mike Gaite of KINOD, Socal), who was here on vacation from the US at the time,helped me inspect the car when I went to take a look at it. As I mentioned earlier, I was really looking for a VVT engine from an NB2, but this front clip was an NB1. But like I said, finding an NB around here is no different from the proverbial needle in a haystack.

I wasn't too excited about the find, but Mike prevailed upon me that this is the swap that he envisions for his own car in California as the VVT swap is a lot more involved because of the complexity. We took a look at the car and it had a 6 speed transmission, so it might have a Torsen diff. So I went ahead and made a deal for the car. Then I went to look for a shop who could perform the installation for me.

Here are some pics of the front clip that we found:

http://i60.photobucket.com/albums/h3...psib2i5syb.pnghttp://i60.photobucket.com/albums/h3...psouoj1kui.png

http://i60.photobucket.com/albums/h3...psu8poibqc.jpghttp://i60.photobucket.com/albums/h3...psd6k9cyin.jpg


I picked the car up a couple of days later during the weekend as I didn’t want to contend with Manila traffic while transporting half a car and dealing with loading and offloading.

Here are pics of the NB and its parts loaded onto a flatbed for the trip from Quezon City to Makati:


http://i60.photobucket.com/albums/h3...psq77lhqld.jpghttp://i60.photobucket.com/albums/h3...psjjskwwof.jpg


We took the car to Makati where my friend has a shop called Car Shack. The trip is a good 20kms through the middle of the metropolis.

After buying the front clip I did a bit of research on the model that I had just bought. Turns out that it isn’t a standard BP4W engine in the car, but a BP5A. Meaning it has a BP05 intake cam giving it about 5hp more. The car is a ’99 Mk2 Special Edition RS that was only sold in Japan. This is attested to by the gauge
cluster with the 6 o’clock resting position for the needles. In the US, the 10th Anniversary Edition was fitted with the same engine. The car also has some aftermarket parts, like tubular 4-2-1 headers, Mazdaspeed plug wires, Mazdaspeed shocks and springs.

After learning all of the foregoing I was stoked! The engine in this car only has a slight torque disadvantage to the VVT engine that I wanted. Moreover, the fuel system in this donor car was the same return system that I have on my car and not the non-return system in the VVT engine. Sure the car had over 186,000kms but a compression test revealed that all four cylinders had good compression.


Here are pics of the shocks that came with the car:

http://i60.photobucket.com/albums/h3...psqfv2fgzp.jpg http://i60.photobucket.com/albums/h3...pshle9eh8y.jpg

This is my car where the engine and transmission from the Mk2 RS is going:

http://i60.photobucket.com/albums/h3...5/IMG_1300.jpg

I plugged in the VIN number on an online VIN decoder which confirmed that the car is an RS special edition. A fellow on MX5Nutz in the UK says that the RS was a trim package and not a special edition and that there are quite a few of them. The specs of the Mk2 RS are: BP05 intake cam, 6 speed transmission, Torsen differential, Bilstein shocks.

It took the shop about a week for the engine, transmission, wiring harness/ecu, to be extracted from the donor car.

http://i60.photobucket.com/albums/h3...pssqwx6mrm.jpghttp://i60.photobucket.com/albums/h3...psowfv4tcd.jpg
http://i60.photobucket.com/albums/h3...ps79xgdfgy.jpghttp://i60.photobucket.com/albums/h3...ps6z0hglbh.jpg
http://i60.photobucket.com/albums/h3...psqrxxbvjs.jpg

The timing belt, and fluids were changed in the donor engine as well as the transmission.

The following weekend, I brought my NA over to the shop so that they could start taking its engine and transmission out.


http://i60.photobucket.com/albums/h3...psgqdn2zsk.jpghttp://i60.photobucket.com/albums/h3...pssnp1alb4.jpg

This is the detuned 1600 that I’m finally going to be rid of.


http://i60.photobucket.com/albums/h3...pslvwf8y4s.jpghttp://i60.photobucket.com/albums/h3...ps0ft79npe.jpg

I was kind of worried about little things about the swap. Especially since NB parts are rather hard to come by around here. In the beginning, I was bugging the electrician about the pigtail for the speedometer since we couldn’t find it at first. He didn’t seem to worried about it.

This is our electrician, Richie Dafon:


http://i60.photobucket.com/albums/h3...psl2zvrjp0.jpghttp://i60.photobucket.com/albums/h3...psapgvsjms.jpg

This gentleman is Joe Paras, the chief mechanic of Car Shack, the shop that’s performing the swap on my car.


http://i60.photobucket.com/albums/h3...pss4gtpspj.jpg

Here’s the gauge cluster from the Mk2 RS being test fitted on the NA dash:


http://i60.photobucket.com/albums/h3...psvaboeg2o.jpg


It took about a month to finish the swap. We had to fabricate an aluminum box to house the cone filter as I didn’t want it to draw in hot air next to the headers. The alternator from the old engine and the new engine were both shot so one of them had to be repaired for the install.

Here’s the custom heat shield/air-box that Joe made. A few weeks later that was replaced by a JR CAI.


http://i60.photobucket.com/albums/h3...pspzeshkvl.jpg


Here’s the the new engine all bolted in and tidied up.


http://i60.photobucket.com/albums/h3...psbpxit84y.jpg

Re-installation of the interior parts:


http://i60.photobucket.com/albums/h3...psejdzlaax.jpg

to be continued: