I've been looking at getting my ECU remapped. It seems I'm looking at spending between €500-800 and will then be stuck if I want to do any further mods. ITB's on the to-do list as I've been given a set of four including injectors but that's besides the point.

A colleague of mine happens to have a dyno in his shop and a dealer in his neighbourhood carries the Det3 as well as a bunch of other goodies.

Would it not make most sense to go Det3 piggyback on my SPI engine for now, considering the before-mentioned pricing on a remap?
Once the ITB manifold is done it should then be sort of simple to get that mod up and running.

It appears I have access to all the support I need (machining, welding, RR, any material from sheet metal to 100mm blocks of aluminium etc.) and cheap, too.

If you were sticking to SPI, can't see a good argument against.

But why not go MPI and stand alone before ITB? Box of bits Megasquirt is not exactly expensive.

What I would check is if DET can do two fuel squirts per engine rotation in fuel implant mode. That's how spi works.

woj said:

What I would check is if DET can do two fuel squirts per engine rotation in fuel implant mode. That's how spi works.

Click to expand...

Very valid point! Thanks, man!


ITB's just for the hell of it so I prefer a simple, (somewhat) cost-effective ECU which will work both ways.
Neither EMU nor MS is out of the question, but if DET3 can get the job done and still get decent results, I'm happy. Won't be braking any quarter-mile records in my Cento, anyway, but would like it to be a smooth ride.


An MPI conversion is not out of the question but does depend whether I can get a hold of head, injectors, fuel rail etc. at my workplace (free!) Breaker prices start at €100 for the head alone and that'd be a good price. Not that I can't find the funds, but I'm sort of a cheapskate... which is why I have the funds in the first place, I guess!

My goal is to use as much as possible of what I already have, unless it won't possibly work. Fabrication will presumably not be an issue - this is only the planning stage. Trying to get my head around what to do.

As always, any input is welcome. This is something completely new to me so consider me uninformed and inexperienced, though patient, competent and stubborn.

It should be possible to convert SPI to MPI (assuming emissions are not going to be an issue!) pretty easily -- you've just got to add extra injectors and some kind of plenum and fuel rail.

FIAT did this (at least) with the 899 Trofeo cars -- unsure of whether they did it to the 1108 Trofeos. Someone posted the homologation stuff (or, at least, a wiring diagram which appears to have been part of the homologation stuff) a while back.

As in the ol' cut'n'splice? I recall (albeit vaguely) something about the 1242 SPI ECU being more capable of controlling four injectors - don't recall where I got that info, though.

A spare inlet manifold came with the car so I've got that to play around with, though I was going to cut it up to fit runners and ITBs to it in some way. Or perhaps just hack up the Punto one, which is fitted to the car and find a third one once I get back to work and a Punto shows up.

Emissions are a challenge of sorts. At the moment the engine seems to be running rich below 2.300rpm, especially when cold the engine kind of gargles and spits, running rough till that point in the rev range. After that it's very smooth all the way to nay-nay-nay-nay-nay.

Even with this behaviour the car was MOT'd back in 2013, so I'm not that worried. Besides, I have a new catalyst in stock.

The low rpm weirdness is why I was thinking of getting it remapped once all service items are over with. The price of a remap is why I started thinking of Ecumaster DET3 or EMU. The latter an acquaintance has experience with and both can be supplied, locally with full support.

Will get going with the search function on the Trofeo-details!

woj said:

What I would check is if DET can do two fuel squirts per engine rotation in fuel implant mode. That's how spi works.

Click to expand...

Page 13, DET3 manual:

"Injection divider
This value stands for the frequency of fuel injection compared to the crank shaft turn. The engine’s cycle (720 degrees of the crankshafts’ turn) is divided into 4 parts (every 180 degrees).
Divider which equals 1 in the Batch Fire mode means that all fuel injectors will be started every 180 degrees."

http://www.ecumaster.com/pobierz/det3/Digital ECU Tuner III - FIT Manual English.pdf


Having read through the manual a few times, I see no immediate limitations.


Perhaps a daft question, but what are the limitations of DET3?

For the price it's a tremendous piece of kit. If it had been on the market 10 or 15 years ago they'd have cleaned up big time.

Don't think it does boost or launch control, though!

fingers99 said:

For the price it's a tremendous piece of kit. If it had been on the market 10 or 15 years ago they'd have cleaned up big time.

Don't think it does boost or launch control, though!

Click to expand...

According to the manual, it does both. (p. 22 and 25 respectively)


The only limitations I can find reading the manual, is DET3's inability to work as a proper SA system and that it can't make use of a wideband O2 sensor.

Seems like a decent kit for "household tuning".