Hi guys,

So this is my first completed turbo project and I thought I´d also document it on a foreign forum, because I´ve sincerely wished someone had done it before, I would have been spared a lot of trial and error.

Basically, base car would be like this:
Engine is a 3 cyl 796 cc, 6 valves, 9.3-1 compression ratio, spurting out a hefty 48bhp and 68 NM of torque. So yeah, it´s a very slow stock car, however it´s a city car so it wasn´t meant to ever be fast.

Why turbo it, you ask? Well, besides the obvious answer ¨Why not?¨, it´s also a very light car to start with (900 kgs with driver and fuel), has very short gear ratios and runs 13 inch wheels, ingredients for good acceleration even if the end power is not big.

For now, here are some pics pre-turbo:

Suspension: SPAX sport springs (30 mm drop) and Kayaba Excel-G shocks, exhaust and some general design (I´ve since then sold the wheels because even if they looked good, the material was weak and they would bend very easily).

More info later on.

 

Original plan was to fit an IHI turbo from an Isuzu truck, along with a Citroen OEM intercooler, and run the turbo straight down from the exhaust manifold. However, since my car has air conditioning and I wanted to keep that, said mounting procedure turned out to be quite a hassle: it would leave virtually no room to access the oil filter.

So we moved it to the right side of the engine compartment, but for that I´ve had to let go of the original engine fan because it took up the necessary space to accommodate the turbo. With that in mind, and with a little bit more clearance, it was decided to go a bit bigger, so the IHI was swapped for a T2 .36 AR taken from a Citroen-Peugeot 1.7 td engine. This way we could use as little boost as possible as the engine would be left stock for this stage.

Fabrication of the exhaust manifold then started, manufactured exhaust and turbo gaskets (some of them on waterjet), oil feed line bought, oil pan modified for the return line. Feed was taken from the oil filter using a sandwich plate.

At first there were a lot oil leaks, and we addressed that by firstly replacing the seals on the turbo, after which I bought a new TPS sensor (mine was faulty) so that the car would idle correctly. And we found that the turbo install would dramatically drop the idle of the car (to such extent that it wouldn´t spin fast enough to drain all of the oil). The solution was to raise idle by modifying the angle of the throttle body to match the original 950 rpm idle, then maxed it out until it made 1000 rpm (this value was read after the charge pipe was mounted, as the ECU intervenes and keeps it in check; with the turbo spinning free it would put out more). With these mods made, all oil leaks were addressed and the turbo ran properly. So you could easily say that this is a the biggest problem this build raised until now, as the T2 is simply huge in relation to the car´s tiny 0.8 L engine.

Here´s a little video I made at this point in the build.

 

Next up, test fitting the FMIC (which came all the way from Taiwan, myself living in Romania), fabrication of the charge pipe and down pipe, re-wrapping the exhaust (this is a must, as you can see it now sits very close to the spark plug wires) and choosing the blow off valve. I went for HKS Super SQV Type 4 71008-AK001, unused, original packaging complete with authenticity certificate, but at half the market price (got pretty lucky there). It's a little overkill but it works great and I don't have to worry about setting it to a specific threshold, it just opens at any given pressure.

 

AFR monitoring is a must, so I've procured the AEM package, complete with a wideband sensor. Cloned the bung from the wideband so I could also fit the car's narrowband original O2 sensor, placed them both after the turbo (rule of thumb, distance would be about ten times the diameter of the downpipe) and fitted the gauges.

Remaining step would be to put the bov to use, thus made a fitting to the charge pipe, t-ed off of a vacuum line and voila, we have boost!

This here was one of the first test drives: extra light on the pedal and shifting early as it was not yet tuned, but that HKS already seems like a very good fit.

 

looks like a fun project, reminds me of my friend who drag raced a Geo Metro, turboed of course. I think it was a 3 cyl.

 

It is quite a fun car to drive now, however it's not made for racing (at least not at this point), rather it's going to be used as a weekend car.

As for the tuning, I've opted for a package deal of installing and setting up a piggyback system on a dyno bench (more specific: Unichip). Now, based on a rough estimate of the engine specs, I´ve calculated a safe boost level of around 0.4 bar (5.8 psi), so the internal wastegate was modified for that specific pressure and tuning began.

It´s worth noting that the engine and fuel delivery are bone stock at this point, so I wasn´t expecting anything special, yet there were a couple of nice surprises: first off, the car has a knock sensor which works great, and setting up a fuel map was a breeze. And second, the MAP sensor sees boost, specifically up to 0.3 bar, and with the margin of error incorporated it was just enough to handle the 0.4 bar that the turbo gave, without having to resort to a MAP module install (or replacement of the original for that matter).

With that said, below you can see a graph of the highest run the car has put out on the bench, compared to a stock Daewoo Matiz (not mine, since it was almost never stock ). The guys fiddled a little bit with the fuel pump and the car ended up leaving the shop with a more conservative tune (about 78bhp and 110 NM torque), just to be on the safe side. All in all, roughly two thirds increase from the original specs seems like a great deal with such low boost, the only thing left to upgrade now is the clutch, as it gives in at peak torque and its making the car lose precious time when shifting gears.

I´ve also procured an air filter (brand new BMC, need a modified adapter for it so it´s not in yet) and front brake upgrades (ATE disks and pads) which I´ll be putting in come spring, because now the snowy season just started, the low ground clearance is a bitch and I don´t wan´t to stress it more than needed.

And here´s a video showing third and fourth gear redlining; once I get the new clutch in and only with me in the car, I´ll probably shave at least one second off of that time. For now it´ll have to do.

P.S: running on 100 RON petrol, best I have available here. No knock whatsoever.
P.S.2: disregard the CEL light, I´m getting a TPS error which doesn´t seem to go away (car idles just fine) so there´s no worry there.
P.S.3: the whooosh of the turbo is just magic to the ears, as you can probably hear on the video, and it completely overshadows the sound of the BOV at high speeds. Not that I complain though

 

Do you have a picture of you injectors? Design wise the same setup is used in daewoos e-tec and s-tec, both three and four cyl. The 1.6 out of an aveo, or the 1.8 out of the cruze/sonic should be interchangeable. Send me a pic of the injector and the connector and I'll compare. The cruzes are 270cc, should be more than enough for 800cc engine

 

This is the injector for matiz, its not mine evidently as I've not pulled anything out of the engine yet. This is for euro 3&4 models which has 4 nozzles, the euro 2 model has only one nozzle, but that's the only difference as far as I know.

If you know something that can match, I'm interested if it would be also suitable for an increased displacement (in the off chance that's even possible, I'm aiming for 1.0L)

 

I've fiddled around with an injector size calculator, and it tells me that having a 270cc size that's running at a recommended of 80% duty cycle, I'll be in the ballpark for about 100 bhp. Realistically, I'll probably be pushing more than that so I guess I'll have to get something even bigger.

 

My buddy just upgraded the injectors on his s4 Audi. Look at the pic, the 2.7 turbo Audi v6 out of his car have the same adaptors. The stock ones are 390cc, he upgraded to 550cc.

Unfortunately he already sold these on ebay