Which ECU?

[StanTheMan]

LSA for the 805 cams is 107 deg

[bruce]

The expense and complication far exceeds the benefits.

[StanTheMan]

The expense and complication far exceeds the benefits.

nothing about the cost. or top HP or anything

its about the emotion the N/A engine and experience stirs within you.

[hamx5ter]

Great chatting yesterday StanTheMan and thanks for the ride ...

i've made a time to do a compression and leakdown test on the engine, a couple of weeks away.

Hopefully the engine is not a lemon. Well, if it is that will just leave me more time to get back on track (so to speak). I'm hoping to get a practice day or two done before the end of the year. I think whatever grudge Hamx5ter had for being abandoned has been well and truly put away. Beautiful drive to your end of town yesterday and the car drove beautifully. Hoping to drive down and say hoy to the mx5 cup crown tomorrow... any excuse for a drive huh?

[hamx5ter]

Finally got the car back after compression test (and rotors changed)

Cyl 1 - 185 psi
Cyl 2 - 190 psi
Cyl 3 - 180 psi
Cyl 4 - 195 psi

That's not bad, i think... less than 10% between min/max compression and within the range i read online for BP engines.

We also put in new rotors to replace my very old and scored rotors. Looking forward to bedding them in as atm, the scored pads only contact perhaps 50% of the front rotors and 25% of the rears. I guess they will smooth out with some driving with the improved braking coming once the pads fit the rotors and the rotors have some pad material transferred onto them.

Now, is this a clever plan? I haven't found a particular tuner / ecu combo to move forward with, but i'm also not in a huge hurry to get the cams in (for now). While i was researching (youtubing) this, I came across Speeduino (which is a DIY MS3). It's not that hard to build the ECU with the appropriate NB8A connector for an easy PnP solution. It's always of course, the tuning. However, there are basemaps for the car, quite an active forum and with some tweaking / autotune it should run acceptably.

My thinking for this would be that since the factory ECU runs the stock engine so well atm, the aftermarket ECU must be able to do as well.

Since it's entirely workable to get an Speeduino ECU for about $350-600 (depending on building it yourself or buying it from a store), i was wondering if i could give putting it together a go, swapping out the factory ECU and seeing if i can get the Speeduino to run the car smoothly (mainly with tuning on the road). If i could do that, that would be a good baseline and a learning experience for me. My worst case (well apart from the worst case of blowing up the engine) would the time and money making the ECU.

Assuming i got the thing running well, i can then look at getting the cams and then we're back onto the next step in tuning the car again.

If i chose a different ecu / tuner at a later point, the Speeduino could probably be given away for a nominal cost or would make a cool paperweight

I'm not going to do this right away; just going to get started on reading the Megamanual when i get the time (i have a ton of things pulling in different directions) so this idea might just warp into a drive-in / drive-out Link ECU installation. I think the Speeduino is an interesting thing though...

Flame away!

[StanTheMan]

I was under the impression that speedonio is somewhere close to the MS2 unless its been improved significantly.

but thats an ECU for tuning yourself. juts like the Ms2/3. people prepared to tune it for you will be even more limited than the Megasquirt.

[rascal]

My thinking for this would be that since the factory ECU runs the stock engine so well atm, the aftermarket ECU must be able to do as well. :

imo, here it’s the devil in the details. OEMs spend thousands of hours perfecting the tune in the car for a reason. (And wouldn’t do that if they didn’t need to)

Getting any ecu to run ok under full throttle is pretty easy, start logging, go for a run (road or dyno) and adjust parameters that aren’t where you want them to be whilst monitoring knock to be safe. Rinse and repeat until happy.

The much harder bit and what takes all the time is everything else. Cold start, hot start, warm start, temperature variances, acceleration enrichment, transient throttle, varying electrical loads.
It’s also the more frustrating bit as having a car stall all the time, or jerk up and down when you touch the throttle, or not start 100% of the time gets old pretty quick..

I had a poorly tuned car early on thanks to supposedly good workshops that weren’t, and it was easily the most unenjoyable time in my 14 years with this car…

[greenMachine]

What Rascal said.

I've said it before, I'll say it again ( ... and again ... and again ... ). If you want to tune it yourself, the road is long and bumpy. A STRONG user community of like-minded souls is vital to support and encourage the DIYer, and as far as I can see that means MS. Otherwise, find a tuner you are prepared to pay $$$ to, and get an ECU they are happy to work on.

Going to an aftermarket ECU is not something that should be done on a whim (unless you are an S&M addict). You need good motivation for power, moah power, and then even moah power. That implies at least a decent budget, so why would you cheap out on an ECU (and its tuning) - one of THE most critical elements in the grand plan? Yes, you can do mods with the stock ECU, but when you get to the point that the stock ECU has to be replaced it has to be seen in the broader context of the 'project' and what you want from the car - power, drivability, and usability.

I get the DIY urge, believe me, having DIYed all my cars, and built a racecar from a bare shell. But I would never DIY my tune. YMMV, but do it with your eyes open.

[ManiacLachy]

Is there an echo in here?

Yep, as the others have said, stand-alones require a good tune, from an experienced tuner. They need to be experienced not only in the ECU, but also the type of car. And they need to care to put the work in, not just run it on the dyno for 4 hours and call it done.

The base-map might start the car, but it will be rough, and auto-tune isn't everything the label makes you think it is. Plus there's far more to sort out than just the fuel map. You can learn it yourself with the help of a good online community, but expect at least 6 months of tracking down fixing fiddly annoyances, only for them to come back later after adjusting something else. There is a lot of chasing your tail and frustration.

If you like to learn these things, and you like experimenting and fine tuning, then a DIY ECU is great. If you just want to drive your car, it's a nightmare.

Finding a good tuner is harder than you think, and tuning/ECU isn't an area to skimp on. Tuning a street car is far harder than tuning a racecar. Start with the tuner, get the ECU and add-ons they recommend. Do not start with the ECU and then try to find someone to make it work.

[hamx5ter]

YES... YEs... Yes.... lol.. Yes, i figured that what i'd hear It does sound a bit too easy to be true.

Right now, i'm very happy with how the car drives (minus the serious lack of power). The 'everything else' that rascal talks about works really well and i am loathe to change that. I abandoned the car because of the stuttering (1 dead MAF and another murdered) and i don't want to repeat that because i'm unhappy with the tune.

I'm hearing GM's advice there...

Going to an aftermarket ECU is not something that should be done on a whim

The thing about the Speeduino PnP is the theory that i can at least inexpensively check out the aftermarket ECU scene and switch back to the factory ECU if things are not working as well as i would like. That's why i thought i'd try the ECU before any engine mods to the car.

Right now i know nothing about the ECUs except what would be on a comparison table on the back of a box, and even that, i wouldn't know what they mean. I guess the way forward is to read up on what all that means, a broad process on what to look for when you give the machine to the tuner and go around and see more cars with different tunes and see just how 'factory' we can get an aftermarket ecu

[bruce]

And it all comes back again to what I said. You will get tiny benefits (if any) for a lot of pain and expense.
I estimate to replace my 2003 Autronic running my 1UZFE, a minimum $5k for a Haltech. No thanks. It runs fine and I've found a tuner for the Autronic for my eventual small mods.

[93_Clubman]

The thing about the Speeduino PnP is the theory that i can at least inexpensively check out the aftermarket ECU scene and switch back to the factory ECU if things are not working as well as i would like.

Agree an interesting side project, & I was seriously thinking about buying the PnP for my NA8, but if you're time poor then there goes all you're spare time especially if you also DIY build - btw Josh Stewart in central Vic aka noisymime on this forum made/makes the Speeduino: search.php?author_id=13470&sr=posts

[hamx5ter]

Thanks 93_C .. reading it now and it's an amazing thread. Yeah, i'm not pushing a timeline so happy to just read and learn about my options as i go along. I'll give the Speeduino / Megasquirt boards a read too..

[hamx5ter]

His ECU build thread was super interesting, and v promising about the NB8As until it just.... stopped.
He also seems to have stopped contributing here since about 2020. I guess the Speeduino project itself has built up enough momentum (and the poor forum seems to have faded in the same time).

Guess the reading will have to continue on over there. Interested in finding out how they went with an NB8A PnP...

[93_Clubman]

Think when I last looked the NB8A PnP was progressing well, but from the website which includes his shop in terms of PnP there now only seems to be NA6/NA8 & the Dropbear, the latter of which is new to me. Btw, the NA6/NA8 & the Dropbear appear to be out of stock in his online shop, so not sure what's occuring, but his online shop does initially come up with a message about the impact of COVID on shipping OS. Also believe he was last logged on here on 24 Aug 2022.