Japanese Engines "Eunos" the same as Miata?

[danss454]

Hi, i'm new to Mazda and Miatas in general, so please bear with me. I am looking at putting a Miata engine/trans/computer setup into an older vehicle. I have been searching for a 'complete' setup, but they are hard to to find at a reasonable cost. However, i have seen on ebay that there are Japanese engine/trans combinations available which are take-outs from Japan. They look like Miata engines, but are basically sold as "Eunos" drivetrains. The sellers will not really comment on how much they are or are-not like Miata's (or if exactly the same?). Can someone comment on any knowledge or experience they might have on Japanese Eunos engine/drivetrains and if i can assume they are the same as a Miata? Thanks for your help! Dan

 

[kcbhiw]

The engines found in the Japanese MX5/Eunos Roadster are identical to those found in the US Miatas. There will be no performance advantage to using those engines.

It's quite easy to find 1.6L engines for $200 give or take. The same goes for the transmissions. Throw in another $100 and you'll have the typical going rate for a 1.8L Miata engine. Where are you located?

 

[danss454]

Hi kcbhiw, thanks for the reply. I wasn't really looking for any performance advantage, i am really looking to confirm that i can transplant an engine setup from a Eunos (aka japanese miata, i guess) using Miata information, like a wiring diagram. I also have some diagnostic equipment for the general OBDII setup, so i also wondering if the Japanese ECU will be able to talk OBDII. I am actually in the Salt Lake City, Utah area. I just moved here, so i don't have a lot of insight on what local drivetrain sources are available. I see the occaisional "Eunos" engine on ebay with the air intake system, fuel pump, trans, wiring, ECU, so that is what i'm looking at right now. If i can find another source for all of the components at once, local (or anywhere that i can bet on getting a decent deal with a good setup), then i'd certainly try it.

 

[kcbhiw]

Hi kcbhiw, thanks for the reply. I wasn't really looking for any performance advantage, i am really looking to confirm that i can transplant an engine setup from a Eunos (aka japanese miata, i guess) using Miata information, like a wiring diagram. I also have some diagnostic equipment for the general OBDII setup, so i also wondering if the Japanese ECU will be able to talk OBDII. I am actually in the Salt Lake City, Utah area. I just moved here, so i don't have a lot of insight on what local drivetrain sources are available. I see the occaisional "Eunos" engine on ebay with the air intake system, fuel pump, trans, wiring, ECU, so that is what i'm looking at right now. If i can find another source for all of the components at once, local (or anywhere that i can bet on getting a decent deal with a good setup), then i'd certainly try it.

The Japanese cars did not have the OBDII system as the 96+ US cars did. What sort of car are you building and do you really need OBDII?

I did a quick search on www.car-part.com and found a few engines in the $350 range located in Calinfornia. Keep an eye on the Spec Miata boards and www.grassrootsmotorsports.com for pulls and/or donor cars.

 

[danss454]

kcbhiw, I am putting this in a Datsun Roadster. I guess i don't HAVE to have OBDII, but i was hoping to be able to use some kind of generic software in order to look at the sensors/codes/etc. I don't have a clue what i'd use on a Japanese computer, however i guess i could find a USA computer and under dash harness and mate it up to the Japanese engine, just as well. I haven't looked at car-part in a long time, so i'll see what's there, nor did i know about the grassroots website, so that is a new one. I see a Eunos setup from Japan on Ebay now, which has just about everything except the driveshaft (which i'll have to merge with the Datsun somehow or have one made, anyway). thanks for the input as i am trying to learn more about the Mazda drivetrain....

 

[kcbhiw]

kcbhiw, I am putting this in a Datsun Roadster. I guess i don't HAVE to have OBDII, but i was hoping to be able to use some kind of generic software in order to look at the sensors/codes/etc. I don't have a clue what i'd use on a Japanese computer, however i guess i could find a USA computer and under dash harness and mate it up to the Japanese engine, just as well. I haven't looked at car-part in a long time, so i'll see what's there, nor did i know about the grassroots website, so that is a new one. I see a Eunos setup from Japan on Ebay now, which has just about everything except the driveshaft (which i'll have to merge with the Datsun somehow or have one made, anyway). thanks for the input as i am trying to learn more about the Mazda drivetrain....

Wow, very cool project! The guys on the Grassroots forum are probably some of the nicest gear heads I've ever run across. They're real nerds about anything from Yugos to Corvettes including, of course, Datsuns. You'll find a ton of info over there.

Might I add another option to your electronics "dillema". Why not consider the Megasquirt programmable ECU? The computer will run about $200 and wiring it in is pretty straight forward. It'll perform control over both spark and fuel. There are tons of them in use including one in each of my Miatas. There are various maps out there for Miata engines alone.

As far as the driveshaft goes, any driveline shop can "re-tube" the front UJ of the Miata shaft to a rear UJ from the Datsun and properly balance it in the end. A competant shop will probably charge between $100-$200.

 

[danss454]

kcbhiw, i have heard the name 'megasquirt' quite often and across a lot of different types of engine uses, but i've never investigated them as i am a believer of 'factory' setups, however at $200 that would be an easy choice. i'll have to research them very well and see if they make sense to try. supposedly you don't have to hack and cut a lot to put the Miata setup into a Datsun, but i guess i'll see. I was thinking seriously of the Ford ZETEC, but another Datsun/Miata swap resource put me off of it as it requires sourcing a lot of parts from overseas. I wanted the Zetec as it was supported by Ford racing with a blower/supercharger setup. However, i see that superchargers are available for the 1.6/1.8 Miata as well. If i can get the Miata drivetrain to work, the blower is next (i don't think i can stuff turbos under the hood as easily as a supercharger). thanks for your help, and if you think of anything, just email me or post here....I've seen prices for custom driveshafts, so i think that's the least of my worries. however, I have found Salt Lake is NOT the place for performance minded car people, but hopefully i can find a shop here for a driveshaft.... dan