Stock air intake KR1-FE?

[Doix]

Hi forum,

As a newbee to this forum and to Toyota I wondered about the stock air intake of the engine in my car. My 2007 Yaris has a 3-cylindre engine and is exactly the same as placed in the Aygo:

http://www.thetruthaboutcars.com/wp-...is_engine2.jpg


From earlier experience I know that the people in America, UK and Germany are more carminded than in my homecountry (The Netherlands) and that some owners try and find out more than possible on their own car, so I hope some owners with knowledge can help me with the following:

As can be seen on the picture the engine has a very small tube to inhale air and it is also placed abeam to the airflow. When inhaled the air needs to traffic through a small pipe, than upwards through a paper filter, than 180 degrees to the thottle valve. In my humble opinion this could me more optimal, also justified by the following experiences by a Dutch Aygo owner:

http://www.verboom.n...ngle=20100331.0

http://www.verboom.n...0826/index.html

Open air intakes do have the problem that those suck warm air from the engine bay and of course tubes and pipes can handle this but corners and bends do have a negative impact on the airflow. So what can be done to optimize the air intake on a KR1-FE engine?

Anyone the same opinion and or an optimized air intake on their Yaris?

Grtz,


Aad ~ Doix

[dj92]

Hartelijk Welkom,
I've got the same engine and last summer, I've tried a tube from the intake to the hole in the plastic wall near the radiator, right behind the grill.
Its diameter was relatively high (70mm I guess), but the engine's power loss was incredible.
I think a better way to keep the intake air cooler is placing a magnet valve into the path of the water which heats the throttle body (the two hoses that are mounted close to each other) to shut this off when it's warm enough (afaik it's only needed to prevent ice buildup inside the throttle body).
The hardest time I've had was when it was 40°C outside and the intake temperature was somewhere between 50 and 60°C.
It was hard to get above 130km/h on the highway...

[Doix]

DJ92,

Thanks for replying and hey, I see some Dutch? ;) ;) I will check this possibility about that valve. Hot air indeed will decrease power, but your remark about preveting ice in the throttle body is a good one, did not think about that .....

My initial question is mainly driven by the following:
are there any quick wins or cheap solutions to get some extra power out of a 1.0 KR1-FE? And mainly by optimizing the air intake, because in my humble, not technical driven opinion, this intake is quit inefficient performance wise (but that preventing ice issue makes my a bit confused) or exhaust.
Of course I am aware that next to the fact that the 1.0 KR1-FE is quit good performing with 69bhp out of 998cc but as we know carmanufactories do make their products balancing between costefficienty, performance, environmental and economical issues and what the market is asking. With this in mind, one can say that the 1.0 possibly is designed for economical purpose, not performance. But that does not mean that possible quick wins or 'easy to do' solutions to get some extra power are not there.

Years ago looking for a Honda Civic 6th gen I read alot about this car and one of the issues I still remember is that in Europe there were two Civics 1.4, one with 90bhp and one with 75bhp. The latter one was launched to sell more, but the only difference between the 90bhp version and the 75bhp version was a small gasket (I think that's the word?). Replacing this small piece (about €15,- or $20,-) gave you back the 'missing' 15bhp.

Something similar I read in an article of a carmagazine about an Opel Corsa C 1.4 (European typing, could be different else in the world) with I thought (!) original delivers 90bhp. A German Tuner, Mantzel, found out that replacing the original airintake (which covers 3/4 of the engine so the air got quit warmed up) by a cold air intake directly pointing to the grille gave an additional 8bhp. That is quit a lot! Imaging what adding chiptuning and a full sportexhaust with manifold included could do to this engine.

Thanks in advance for replying and kind regards,

Aad ~ Doix

[dj92]

Blocking the exhaust gas returning valve would give a higher performance, but sadly all newer ECUs (Euro 4 and higher iirc) check whether it operates correctly.
IMHO the easiest way to get mor power is shifting later :D
The Yaris performs quite good even at higher RPMs because of the VVT.
Fuel consumption rises in my case from about 5,2l/100km to 6,5l/100km in-town.
I saw someone experiment with a manifold spacer, maybe this could help a bit here.

[cali yaris]

^ Exhaust valve?

One of the first mods we do here is re-route that throttle body coolant line to loop on itself, instead of going through the throttle body. But a shut-off valve would be preferable for you guys in colder climates.

This does not affect the ECU and does increase performance slightly.

[maxcrack]

Hi, I have tried to do this:





I got improvements from 3500 rpm and in 3rd and 5th gear and even a nice rumble...

Look here: http://www.toyotaclubitalia.it/forum...998cc-12v.html

[dj92]

Recently, I bought a 100mm (approx 4") dryer tubing and installed it.
I adapted it to the filter box with a part of a plastic bottle, the other snapped well into the hole beneath the radiator.
The boost is incredible, I begin to fear my car's power :D
I'll check the 0-100km/h times on an off-road track (that has a nice sealed surface) soon, with and without it, this should be closer to road use and cheaper than a dyno test :D