I semi accidentally found the Rev limiter in my Copen...

Excuse

Hi Marnob, please excuse my ignorance with these questions.

So far my other mods have been pretty standard - a cone direct air intake squeezed next to the intercooler, a straight through 2"exhaust (with 30cm of 2.5"to get a bit more noise) and a real-time engine temp sensor / display. I'm always interested in inexpensive improvements that don't stress the already insanely stressed 659 any further.
I also recently discovered how to make the blowoff valve (?) give excellent turbo noise every time you come off the throttle, for just $6 (check it in the Mods forum), by venting to the atmosphere instead of back to the turbo.
Firstly, what is the D-Sport ECU, what do they do better, how do you know if you can fit one & how much are they? All Copens in Australia are unchanged 659s just shipped out of Japan which makes me think it might match.

Second, after some basic research, I think I understand the function of a boost controller & I would go the manual path - it's not like I'm tuning an R32 Skyline GTR, it's a Copen.


This is a manual boost controller if I'm understanding this correctly. This is the 'Turbo Smart' controller (AUD$$116.45 incl shipping) with the settings done using that top dial. Is this pretty much what you installed?
Also, is the 659 an internal or external wastega te? I'm thinking that, if it is external, I would have to re-connect the blow off valve back to the turbo to fit it. Does this sound right to you?

I'm assuming that your goal was to increase the boost psi from standard in order to flatten the boost curve, yes?
Lastly, do you think that it stresses the 659, where did you get it & how difficult (read: expensive) is it to fit?

Sorry to bombard you with questions but your post really intrigued me. Cheers, Brian

 

If your Copen is Aussie spec the Dsport should work. I put a unichip on mine.
The original ECU retards the timing as the revs rise to keep it under the Kei class limits so ECU upgrade is a must.

I wouldn't bother with the boost controller, the original turbo runs out of puff and starts dropping boost at high revs anyway. You might make some gains low down. Only real fix is bigger turbo and intercooler.

 

D-Sport ECU's are not cheap and neither is your Unichip. Getting one from Japan will take months to arrive as there are no flights.
It took 3.5months to get a radiator!
I understand what you are saying. totally agree but what I am saying about a manual boost controller is it is a great cheap way of increasing power in a standard Copen installing it yourself.

 

Yes I see what you have done. I have seen that done before by another guy but if your still using the standard Blow Off Valve it wont achieve any more power.

 

Hi Brian, no problem..
A D-Sport ECU was produced in Japan and will fit our Aussie Copens.
It increases boost etc and is basically like have a remap.
It just replaces your standard ECU and plugs straight in.
D-Sport produce a range of products from intercoolers to suspension etc.
They are like a racing type company that have after market mods.
Of course having a Unichip like Jez or a D-Sport makes a great difference to power if you can afford it.
If you look around on say Gumtree or E/Bay you should be able to get a manual one cheaper than that. Mine is a SAS one I got from Gumtree for $40 new, but dont get a no name brand. A Turbo Smart one will do fine.
I have been running mine since last year and no problems.
I dont cane it to red line or anything like that. Probably 6500 is the max I have gone to but the sweet spot is really from 3k up to that.
In third gear heading onto the Motorway it pulls really well now.
Like Jez says it runs out of puff.
What you can do is mount it on the nut on the drivers side where you modified the pipe to create the valve sound.
Its the one on the pipe where the engine cover used to bolt onto.
Thats where I mounted mine. It will need to go upside down to make the hoses easier to install without kinks.
Just take the grill off & you can take the small hose off the Actuator and the turbo and mount the controller & run a hose from each to connect to the controller. I ran one around past the aircleaner and back to it. The other just goes straight from the actuator and its done.
Tune it yourself until like I said, makes fuel cut and then go back a click. If it doesnt cut then your sweet.
If you can replace that plastic intake with a stainless/Alloy one it will make a big difference too.
I can post a photo if you like.
I am in the process of putting a boost gauge in as I am curious as to what the boost is.
I am also making a valve with a way of switching between standard boost and my controller. This will have a small switch mounted under the gear knob so I can just flick it on when I want maximum power.
I will use a 3 port MAC Valve to divert the pressure.
The standard Copen has an internal waste gate.When you remove the grill you can see it.

 

Thanks Marnob.
Yes, photos would really help me to get my head around it, if you have time.
I went to Dyna-Tune & he reckoned don't do it. I'm pretty confused now. I'll approach another shop tomorrow for an opinion.

Which brings me back to the D-Sport ECU. Not sure if you have one, but if you do, I don't suppose you can photograph that too?
Nengun have discontinued the D-Sport..
monocolle-motorsport still have it & they say From their page:
"

Dsport sports ECU (sports computer) Daihatsu Copen (L880K)
83,000Yen"
"The ECU kit which realizes 11.9 kg of best output 80ps/'s greatest torque, m in spite of being the simple wearing with the coupler. I fully draw potence hidden in the JB-DET engine of the copen by the setting that is a high level supported by many tests."
Also "Best output (net): 59kw@6,400r.p.m, 117Mn @3600rpm"
However, "Not english manual is include" but a set of Iridium spak plugs comes with the kit.
I imagine that I could find an English manual on the net. Prices - Y83k / $1,100 + $60

You seem to know your stuff really well so I guess, if I was willing to dig into my savings account (I hate doing that!)do you think that buying & fitting a D-Sport would be worth it & that it wouldn't bugger up my engine? Everyone seems to say you just take out the OEM ECU & bang in your D-Sport & iridium plugs. As someone with knowledge, does this sound correct?
Thanks, Brian

PS Yes, the turbo kicks in around 3250 & yes, I rarely go past 6k rpm except when I'm distracted & not paying attention. The engine is so smooth that even if I have the radio on I'm "Flying by instruments". I regularly change-up in 1st, 2nd, 3rd @5k or so RPM, 4th at 4k. "Extensive research" down here on local Canberra country roads got the buttoned down Copen to 150kmh at which point the research was called off. The trick is to hold 4th to 6250rpm.

 

Thanks, great info as always!
I don't know how you shift at 3k rpm. In 1st, that's a blink of the eye. I can notice boost at 3250 but I'm sure you're correct. I might change my habits to what I call "Short Shifting" at 4k. Problem is, however mechanically sympathetic you are, the engine is just too smooth to complain.
Yes, until I hit 40deg I ask very little of the engine, then after a drive I let the turbo wind down at idle for 30-60 secs before turning her off.

 

The D-Sport ECU is expensive now..at one time it was around 50K Yen which at todays prices wasnt bad. You could even get them at 40 second hand sometimes but not anymore.
There is also a guy who will remap a standard ECU to similar specs in Japan or you can do an exchange but with the Covid crap going on that is not an option until Air Freight comes back online.
Sooo, like I said above, just fit a Manual Boost Controller.
That dino tuner is wrong about fitting one. The great thing about the Copen is it has a fuel cut so as I mentioned it is a great protector when your go to far & also you dont need a boost gauge when tuning it. DIY, easy as.
The ECU will take care of the fuel mixture anyway, hence the cut off.
The Ultimate Copens have a 8500 redline too, same gauges I have fitted.
I also find with my tuning I dont have to push the accelerator far at all to get it to rev now. I feel the turbo kicks in under 3k so perhaps 2.5k. I will take a bit more notice next time I drive.
The D-Sport ECU will be fine. Heaps of them fitted in Japan, they are just expensive. Thats why I decided to fit the controller. Should have done that years ago..seriously it brings the standard Copen to life!
The JC-DET engines were fitted to the Storia which never came to Aust unfortunately.
They have a couple of things the JB doesnt have. Longer stroke and VVT which as stated above makes them 715cc.
A swiss guy swapped out his Copen for one and it flew! Traction was the problem then he said, breaking loose in 3rd.
The standard Copen with a D-Sport ECU will fuel cut at 15psi so I am curious to see what the psi is on mine with the controller at full boost?
I now have all the fittings sorted, had to modify one to fit the gauge line into it, so I just need to find some time to fit my boost switching and gauge.
Will put some photos up of the setup now and then later when its finished.

 

I'm following your advice, but because I'm a better carpenter than car tuner, I'm getting it installed by Dyno Tune on Wednesday so I don't make anything go 'bang!'. Total cost is $280 but that's ok for Canberra where everything costs more. Plus, I've said to err on the side of caution with the boost increase.

I'll be interested to see the before & after dyno results. Also to see if her already excessive drinking problem changes. I only get 7-8L/100km now. I also want to see if I replicate your results, with less accellerator

Afron told me he changes up at 3k rpm, I was sceptical but tried that today. Terrible. Do not scratch your nose in first, 3k is almost instant. Other times I found the poor little engine struggling under load. Maybe he lives in a city with congestion problems. Here in Canberra the roads linking the various districts are 80kmh zones, where I do use 5th at under 3k when just cruising. But I'm not doing the 3k rpm thing again, my Copen was almost a traffic hazard. I'll set 4500rpm as my normal change point in 1-3, 4th to 5th are pretty close so I'll play them by ear as normal.

Anyway, thanks for your help, I'll let you know how it turns out, B

 

Fair enough but it seems the tuner does not know much about the Copen. No one really does as its getting on in the years now and they stopped importing them in 05.
They will not be able to access the ECU either so all they can do is adjust the boost.
In the Unichip case, if you read his original post, it is very difficult to tune it.
I spent many hours looking for a program that would do that via the OBD2 but the jury is still out as to whether the Aust Copen has that. I think it might not.
Most dont in Aust.
You can not do any damage as it has a fuel cut? Thats my whole point.
Anyway, they will find it as there is no other way of working it out. A boost gauge will give them the psi but I doubt they will know what that limit should be, hence the fuel cut is that limit and I am sure they will find that.
The Turbo is very small as a lot of people have pointed out and has limitations from that.
If you do not get any performance increase it will be because they havent found the fuel cut point or they have just backed it off to close to the standard setting.
Your Blow off Valve will be your bottle neck though as it is known for not holding boost well at all.
Hopefully they notice that and may suggest some changes.
Ask them if they found the fuel cut point?
If you do decide to adjust it then one click at a time. The arrows show you which way. Take it for a spin and you will know straight away if you reached the limit.
It will cough and die under acceleration so dont freak out. You just cant accelerate above 3k coz as soon as the boost comes on the ECU cuts fuel.
When you back it off again it will be fine. That is your limit so you lock it with the allen key and thats it.
Interested in how you go...
Mine is really good on fuel. Perhaps you are heavy on the throttle as you tend to rev it high most of the time?
With a boost increase you should find you wont need to do that as much so I should expect the fuel usage to decrease?
Another reason is it might have a boost leak but the Tuner should notice that?
I dont need to use much throttle to get power.

 

On the subject of Boost leaks, I found one on my Audi I used to own by fitting a tube to the inlet and blowing smoke from a cigar down it.
For the Copen I havent done that but a couple of places are of concern.
The Air Cleaner rubber fitting will be perished by now. Remove the air cleaner holder and have a close look at it. I replaced mine recently. You can still order those from Toyota.
The S hose from the Turbo to the Intercooler probably should be replaced with Silicone or similar. Heat is the enemy for rubber.
Any hoses around the blow off valve, intercooler pipe and vacuum should be checked thoroughly for perishing and leaks.
The actuator hose that goes to the metal pipe on the drivers side & the hoses up the top near the throttle body.
The metal pipe goes up the side of the engine and comes out to rubber hoses at the top.
Any Boost leaks will cause excess fuel usage.

 

Ok, you have given me a few things to think about. I will mention the fuel cut out situation specifically to them so they more or less turn it up until that problem hits. I have told them that the ECU is designed to limit power because of the Kei class rules. Once I have her back I'll print off all your notes & go through them carefully & methodically.

When I bought her, I went over all the pipes etc (it lived as a toy for 17 years, thus a rotten exhaust) to look for obvious problems or perishing & all seems good. A few have been replaced by previous owners. The main intercooler hose fell off but that was a case of just buying a metal clamp to hold it on. As for the air intake, I simply removed the stupid OEM one & put a new K&N style cone filter on, a Copen specific one.

As for this mod, I'm really just dipping my toes in the water, this is my first turbo (I know jack sh*t about turbos). My previous cars have all been more common atmo models, so I really just fixed the crap that should have been done at the factory, intake, exhaust, extractors & the odd ECU re-mapping, simple. But as you say, there is no such thing as a Copen whiz to turn to. I'm not spending much so if it doesn't do much I won't be too upset & I see that I'll probably have to fiddle a bit. I'll post a pic of what's been done & probably ask you a question or two. Thanks again, B
PS What is the standard boost on the Copen?

 

Ok, but you still have the standard ribbed rubber fitting for the aircleaner?
That is the one that needs replacing and was perished in mine.
I run a D-Sport air element which has a much bigger opening to allow more airflow. My air box is also modified with small holes to allow the same. I copied the configuration from a stainless aftermarket one in Japan. This way it still looks stock and is not exposed to the elements of water/dust like a pod. There is a post on this forum somewhere with photos I put ages ago.
Some photos of the controller & piping. I also have a forge boost valve fitted which regulates & smooths it out for the blow off.
This will change once I fit the boost gauge and MAC Valve setup.

 

Hi Marnob,
Well, we installed a Turbosmart manual boost controller. Thanks so much for your help & patience!
Now that I've seen it, yes, if I were more knowledgeable/competent/confident, it is a DIY job. But for someone like me, with the first turbo I've ever owned, I think the extra money was worth it. Total was $274 all up.
I printed out your notes above to give the guys what they needed to get the best result.
Now the boost runs up to a max of 14.8, damned close to the 15 ECU limit.

The results speak for themselves. Honestly, I couldn't be happier in terms of bang for buck & in how she feels now.
The engine simply feels 'happier', more balanced, like a weight has been taken off its shoulders.
Now, rather than performing like a Yaris with 4 fat people on board, it just does the business, no questions.
It is as though the bar has been raised everywhere (unintentional pun) & I can upshift at 4k (which usually takes you back to 3k with the close ratio box).
The engine in no way feels stressed, in fact just the opposite. It feels just great.
Watching my engine temp display, I notice that she runs maybe 3deg/c hotter but that's not a problem.
As you said, I also use noticeably less throttle & actually expect that her drinking may decrease.
Your estimate of 20% increase was actually pessimistic, we got 30%.
Combined with the fantastic 'vent to atmo' turbo noise I get every time I come off the throttle, driving is even more fun than it was 6 weeks ago! And 6 weeks ago I already loved it.
If you haven't already, I'd recommend you try the 'vent to atmo' mod I posted, even just to see if you like it. If you don't, just reconnect it, nothing lost except maybe half an hour of your life.
Anyway, thanks, it turned out better than I expected.
My only remaining question is: why didn't Daihatsu, just do this & fix the crappy air intake before they sent it out? They were asking MX-5 money & if they had, I think they'd have sold a lot more tiny sports cars.
Cheers, Brian
PS I might post this to the 'Mods' forum with a link back to your instructions.

 

Good work! You may notice in my photo I have a HKS Blow off Valve already fitted.
That is the another weak spot for the Copen as it leaks and doesn't hold pressure well.
I have a larger Intercooler and pipes fitted which helps in the Summer to keep the cool air coming in.
The reason they didnt do extra stuff to it is coz its a detuned car in Japan for Rego and Insurance purposes.
Unlike here that car is really cheap to Register & hence its popularity.
Its main problem is breathing, inlet and outlet.
There are so many extras made for this car in Japan its unbelieveable. So easy to make it a little pocket rocket so the aftermarket stuff was very popular.
I knew you would be happy with the results. Cheap upgrade isn't it?
There is no much more you can do to push more power out of it now except perhaps ditching the turbo for a larger and more modern one. That will entail more turning though as the fuel needs to be accurately adjusted.
Thats where the ECU becomes a problem and the D-Sport one comes into play or a Unichip perhaps.
I figure they just fitting the controller and then adjusted it to fuel cut and did some dyno runs to get a before and after?
I dont believe they would be able to adjust fuel/air ratios with that type of ECU?

 

Thanks! Yes, I doubt they could do much about the fuel/air mix but I will ask Josh the guy who did it next time I'm around there.
I'm pretty sure he just followed your instructions & wound it back a notch when it started arguing with the ECU.
The before & after dyno results accurately reflect how it feels - better absolutely everywhere.
I'm now completely satisfied with the performance so I won't change the turbo or upgrade the blow-off valve, ECU etc.
However a better intercooler would be good but I'm not sure it would fit in - the front end already has the radiator, intercooler & pod all squeezed together, but that is something I would fit if I could for our 46deg days. I might ask you about that.
As a precaution, I've set the temp sensor to sound the alarm at 100deg, but I look at its display a lot when I'm driving anyway, especially in summer.
We're lucky they ran this model for 10 years so, as you say, parts from Japan aren't hard.
I got some nice Xenon headlights to replace the dated Halogen ones. Seems HID won't fit.
I think I've fixed the breathing with the pod air filter, your's is probably superior, & the new straight through 2" exhaust (with 30cm of 2.5" for some echo).
I know that Kei cars have restrictions & the rego situation there, but I think Daihatsu should have just changed the air intake & boost controller for Australian sales. The stock performance (and its wild impracticality) were most criticised when they launched it here. I think they'd have sold more, they were bloody expensive little cars if you calculated cost by the kilogram. I doubt they could legally have done much to the exhaust due to ADRs, unlike me.
This is my 3rd Daihatsu in a row (2x GTvi with 150k km) & they've been great. The only reason I bought a 2003 retractable roof car was because it was a Daihatsu. A Peugeot or Merc, let alone Chrysler, not a chance in hell.
Anyway, it has turned out to be the best value performance mod I've ever done, so thanks! I plan to keep the Copen as long as I'm back in Australia. I look at cars & I only the new MX-5 is of even vague interest. A Copen sort of attaches to you & letting go would be hard. I can't explain it rationally. Cheers, B

PS The cost of my car & my bike has been paid for by one customer, a 16yo severely mentally impaired young man. Originally it was the Copen that launched our relationship, as he loves being. However, teaching him to ride pillion, with some foot pegs I machined & fitted to my bike, has been very, very profitable as I get the same per km rate for car & my 3l/100km bike. I ride & drive our country roads, much like I would alone. So I give him the excitement a 16yo needs in a safe way.

 

Job done!..Don't you just wish you had done that years ago. I should have as well although after doing the mods on the intercooler and exhaust etc it was going much better anyway but the controller just takes the Copen to the level it should have been.
I got my intercooler from Japan and apart from being a lot larger it was designed to fit in the same place the original was.
One thing I have been meaning to do is re paint the black pipe coming from the intercooler. Black is not a good colour for something that needs cool air so its gonna be chrome colour. I have toyed with the idea of getting it chromed. Will see what the turn around and cost is.
I also have the stainless pipe that came with the piping that was sposed to replace that black one but with the larger intercooler it wont fit. I may just get that reshaped which might be a cheaper option with no down time.
Good luck for the future...

 

Thanks! Yes, it does feel like that's what the designers actually intended, not stressed at all, it feels like someone has slipped a nice CA18DE in. I bought in Dec 18 & it had spent 15yrs as a toy car. Only 40k km but a rotten exhaust from condensation & tyres with 90% tread but 9yo. Now she literally works for a living!

I split daily duties 67/33 in favour of my "smallest, lightest maxi-scooter". It actually carries more, nice seat & will sit at 115kmh forever. The Copen's gearing means 105kmh feels more mechanically sympathetic. Plus it's 3L/100km v 7.5L/100km. I ride it like I stole it, but my Suzuki Burgman doesn't worry me, it's known to be bullet proof if serviced correctly & any parts will be dramatically cheaper than Copen bits like clutches.

I did all the work mentioned before then, as you know, changed the wastegate to vent to atmosphere for that addictive turbo noise whenever you lift & thought that was it. She was still slow til she got moving but I thought "hey, she's gorgeous, fun to drive, sounds nice, goes ok once moving & handles like a cat on carpet" - finished.

Then I read your posts about boost controllers & the ECU. Very interesting. Knowing nothing about the car or turbos generally I was somewhat confused so I read up & picked your brain! I decided DIY made me uncomfortable, but as it was a quick job I ponied up for Dyno Tune, I also wanted before & after dyno runs. Now I'm happy. I'll be interested see what AFRON says when I post the mod for people, like me, who know nothing & are worried about the engine going boom. I'll refer people to your post about how/why so they can print & give it to their tuners like I did.

She had her first proper run through the tight twisties of Uriarra on Sunday following a Commodore, going hard, who would lose me in the short straights but just could not get me off his bumper. We both had a laugh & swapped war stories at the Murrumbidgee when we stopped. That's what is so good about Copens - everybody loves them, even hardcore Falcodore men.

Now maybe I can help you with 2 small but helpful things I've done.
You know that ridiculous foot rest which only a Japanese ballet dancer wearing her shoes could use? That came out & I made a small footrest on the black plastic pedal-side where I can rest my clutch foot. I glued a thick right-angle plastic piece behind then built up a 15cm footrest of 2x1" (with some aluminium to make it wider - it was trial & error) in front of the supporting plastic & that black, sandy grip for stairs etc on the face. Sprayed it all in matt black, a very easy but excellent build. I find contact adhesive liberally applied & properly used works well.


Next is the damned seatbelt. I sprayed it liberally with tyre shine so it would retract. Good, but it still tended to bunch up. So I put a piece of plastic over it & that solved the problem. I used velcro on the seat's seatbelt fitting so I can undo it to move the seat. Then I moved the seatbelt above the seat fitting as it was just too low. Again, built for average Japanese bloke. The bit of plastic I put in earlier holds it in place.


I'm going to ask you more about the intercooler at some point. I have maybe 5cm gap between it & the pod. That's something I'm definitely interested in. How can it be a lot larger yet fit in the same space?

 

After looking at the black intercooler pipe, I definitely wouldn't spend up on chroming it, except for looks. All "chrome" paint looks crap, I had a bit of a think about it last night & it will still be black inside. Thinking about the physics of it, the black inside is good as it will absorb more internal heat than a [completely impossible, theoretical] chrome inside. A layer of chrome on the outside could be counter-productive by trapping the heat from dissipating into the surrounds & bouncing it back into the pipe.
Chrome on the outside will only be useful in dissipating heat coming in from outside and it is under the aluminium bonnet anyway. Unless you're stuck in traffic all the time, I'd think that the wind from the grille would more than make up for heat from the sun transmitted through the thin aluminium.
Anyway, just my thoughts. It certainly would look pretty cool but that's about the only reason I can think of to do it. BTW do you know of anything that removes the inevitable ugly silverish-green superficial corrosion that the aluminium engine gets? It would be nice to remove the vanity cover & see a clean engine.