1999 Yaris Engine Chip

[Bod&Hammie]

Hi,

Has anyone ever fitted a tuning box/chip to a 1999 1.0L.

If so can they recommend a good one or any way of squeezing a little more power from the engine.

Thanks,

Bod

[Madasafish]

Don't bother.. The engine will be so worn that the chances of getting any extra performance is negligible.

[Bod&Hammie]

Well maybe so but I thought it was worth an ask.

[yossarian247]

Chipping a naturally aspirated petrol engine of any sort is generally reckoned to be a waste of time. They just dont have any real scope for power gains. 

[Bod&Hammie]

In all these years I never realized that chipping a normally aspirated doesn't work. I've always chipped my diesels (obviously turbos) but never gave that a thought that it wouldn't work on an n/a.

I asked the same question at the same time in a Lexus forum about my GS300 and they came back with the same answer.

Oh well, every day is a school day.

Thanks guys

Bod

[MikeSh]

'Chipping' or loading a 'tune' into the ECM isn't usually of much value unless done with physical changes - eg. to intake/air filter, exhaust, different cams or simply using a higher grade of fuel. (Using 97 or 99 RON instead of the standard 95 allows a more advanced spark which gives more power * ).

What a lot of tunes/chips do is to alter the throttle response so it is more sensitive - less pedal travel for a given throttle change. This makes the car feel more responsive ("Wow, this tune has really made it come to life") but doesn't actually give you more power or torque ... and may make it harder to do fine control like parking.

* Typically about 5% per 2 RON. But then you you need to use the higher grade all the time (or risk engine damage). Just putting higher RON fuel in a '95' car doesn't give you more power unless the car has some ability to change the timing with octane changes. And most butt dynos couldn't tell a 10% increase in power anyway 

[bathtub tom]

As I understand it, a higher RON petrol doesn't have a higher calorific value, it just 'burns' slower.

How would this deliver more power?

[yossarian247]

18 hours ago, Bod&Hammie said:

In all these years I never realized that chipping a normally aspirated doesn't work. I've always chipped my diesels (obviously turbos) but never gave that a thought that it wouldn't work on an n/a.

I asked the same question at the same time in a Lexus forum about my GS300 and they came back with the same answer.

Oh well, every day is a school day.

Thanks guys

Bod

Its one area where diesel engines differ massively from petrols.

Its easy on turbo diesels, just turn up the turbo boost and the fuelling, hey presto you have a faster car (albeit at the expense of black smoke, MPG and engine longevity if you go too far with it).

But with NA petrol: turn the boost up? It doesn't have a turbo. Turn the fuelling up? You just make it produce blue smoke, kill the catalytic converter, soot up the plugs, decimate your MPG, and don't even make it much faster. Like driving an old car with the choke out all the time!

[mickburkesnr]

I looked in to this chip mod thing, and I reasoned that adjusting the timing on my engine would be a better gain of performance. But what you gain in top end engine power you loose on acceleration and vice versa. To me it means more to accelerate quicker, so I'll be advancing the timing on my engine instead of messing about with chips.

[Cyker]

Maybe you can adapt the Aygo 1.0L supercharger kit for it... 

@bathtub - Higher RON on its own doesn't do a thing for power; It's only really useful if the car has a turbo (Fuel with higher RON = Can run higher boost) or has a higher compression ratio than normal, then the engine can run the engine at optimal timing instead of having to !Removed! the spark to avoid knocking.

 

It's a funny thing vs diesel as with diesel you effectively want a lower RON because diesel is immune to knock so you can have as much turbo boost and compression as the engine can take without exploding!

The only cars I've been in that actually needed higher RON were tuned Subaru Imprezas (aka the standard Boy Racer car). I'm told by some of my States-side friends that they sometimes have to use higher RON when they go down to the coast otherwise they get knock, but it seems their standard fuel has a much worse RON than ours...
 

[MikeSh]

5 minutes ago, Cyker said:

 but it seems their standard fuel has a much worse RON than ours...
 

That's sort of true, but not. 'Regular' petrol in the US is about 91-92 RON whereas ours is 95, so it is a bit 'worse'. But they also use AKI not RON to designate it, so their regular petrol is actually 87 AKI - the number on their pump is 87.

So when Americans say they put 87 or 89 gas in their tanks it's not as bad as it sounds to us. (And conversely if we talk about putting 95 in they may wonder what kind of rocket we are fuelling.)