Gday New User, First Post About NA6 Engine Swap

[jerrah]

What colour was the smoke? If the weather was cold and the car is damp there is a good chance it was just steam evaporating from the exhaust system.

[mr_rotary]

Didn't someone here post up not that long ago, back to back dyno results from the same car with both Aus and Jap ECUs?

I'm pretty sure there was no difference either way though.

I beg to differ as jap spec fuel is 102RON vs 91RON for Australian fuel. I certainly noticed this when trying to run a Eunos roadster on 91RON! They run a LOT better on a minimum of 95RON so I don't see how the computers are the same when there is a vast difference in fuel types so hence you would get more power straight out of the box from a Jap spec ECU.

Also with my Mines ECU, they specifically state in the writeup that they are tuned to a mimimum 102RON fuel.

[Fatty]

Didn't someone here post up not that long ago, back to back dyno results from the same car with both Aus and Jap ECUs?

I'm pretty sure there was no difference either way though.

I beg to differ as jap spec fuel is 102RON vs 91RON for Australian fuel. I certainly noticed this when trying to run a Eunos roadster on 91RON! They run a LOT better on a minimum of 95RON so I don't see how the computers are the same when there is a vast difference in fuel types so hence you would get more power straight out of the box from a Jap spec ECU.

Also with my Mines ECU, they specifically state in the writeup that they are tuned to a mimimum 102RON fuel.

this is an oft quoted opinion, however the only back to back dyno report i've ever seen (as jeo mentioned) where they swapped a jap spec, and an aus spec ecu, on the same car, on the same dyno, on the same day, showed no difference in power.

the car may "feel" better , or be more responsive or whatever subjective terms you would like to use to describe it, but no-one has ever objectively shown (to the best of my knowledge) that a jap spec ecu will release the untapped power in our aus spec cars.

sure the tune might be different but to jump to the conclusion that therefore there must be more power, is a leap of faith and nothing more imho. you say "there is a vast difference in fuel types so hence you would get more power" but no-one has proven it that i know of, however people often make this claim (and often, those people are trying to sell you a "magic bullet" jap spec ecu)

i dunno, this may seem a bit harsh but i see this claim made over and over, and the more it gets repeated the more people are willing to accept it as fact, when i have yet to see any proof!

/ end rant

[tbro]

nah the car wasnt wet at all, it was covered in ice in the mornings. the smoke was very white though and the engine oil started running out very quickly, not sure though

Hey m8,
Let me throw you a curve ball, fit an NB6 engine to your car if your motor isn't healthy.Fitting a 1.8 isn't dead-set straight forward,ecu wiring etc to do as well. Fit a NB1.6 with a lightened flywheel, extractors and you will have a economical straight forward engine swap.
In case you don't know I have both NA's, a 1.6 with a nb6 and a Clubby, and driving them on the road,you can not feel any great difference, on the track the Na6 is actually 4 secs quicker around QLD raceway.Ok the clubby is stock and Scooter has cams and a Microtech,lightened flywheel,extractors and Loch stewart CAI.
Fit the 1.8 and you will/must fit a bigger diff from a NA8 or you'll blow whats there.
So price up a NB6 and I think you will be surprised.

My 2c worth.

Terry

[jerrah]

White 'smoke' doesn't sound like oil.

+1 I'm very happy with my NB6 engine.

[mr_rotary]

i dunno, this may seem a bit harsh but i see this claim made over and over, and the more it gets repeated the more people are willing to accept it as fact, when i have yet to see any proof!

Water is wet, the sky is blue and higher octane fuel will give you more power. Why would a country with 102RON fuel tune their ECU to run on inferior 91RON fuel. I don't see how hard that is to understand
I guess you did not change fuels on the dyno, and most importantly, you require an engine dyno to see the true results as at a guess there is only a handull of HP difference between the two ECU's. I suppose the easiest way to see the difference is to get hold of a Japanese Eunos Roaster Brochure

[StanTheMan]

I can run 100 RON fuel here my aussie ecu.....in 1989 that wasn't available here. The MX5 was built & desinged as a very cheap sports car with many shortcomings to reduce production costs. It was also built for the North American market. If it passed California emission laws, this meant it would pass every other emission law in the world at the time. Why on earth would you bother to have a seperate production run on a ecu just to advance the timng for 100RON ? When it can run on 100Ron on the standard ecu regardless.

Go back to 2000- 2001 or some time when the Americans overquoted the offical HP output. It turned out japanese hp is a bit differnt to US hp.....someone flocked up the calculations. There was a massive stink about it. Mazda was refunding money for disgruntled owners who felt mislead by mazda's figures.



Until you get mazda to confirm that the JDM ecu is different . Or prove it with some dyno charts in a viable way, Its an Internet myth.