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Is200 Remap - Standard Ecu - Big Difference

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Lol started a little short story section here,good info tho,yea u can set the valve thing to b open all the time,if u go on the lexus is200 facebook page one of the guys has done it,very hard to get to tho he said.

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I'm sure that's very informative Noby but as soon as you start talking about 170N/M of torque and the like I get totally lost!! I don't know what N/M of torque means and now I'm very confused lol

So basically.. it's not vvti kicking in, it's a valve that opens on the exhaust at 3800rpm that gives you better acceleration. So it must be possible to just have the valves open all the time giving the more responsive throttle throughout the rev range.

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I'm sure that's very informative Noby but as soon as you start talking about 170N/M of torque and the like I get totally lost!! I don't know what N/M of torque means and now I'm very confused lol

So basically.. it's not vvti kicking in, it's a valve that opens on the exhaust at 3800rpm that gives you better acceleration. So it must be possible to just have the valves open all the time giving the more responsive throttle throughout the rev range.

sorry mate.. NM is just a torque figure it can also be listed in lbft(pound foot) if you understand lb ft better??. the higher NM a car has the better it can pull at lower revs. the IS200 has 196NM in total so it will pull better at lower revs compared to another car with say 100NM of torque. yes VVTi does not kick in or activate. becuase its already on from 750rpm to 6200rpm. the kick is the ACIS opening a shorter intake path to speed up the air entering into the cylinder. intake path/port is the tube which the air coming in travels through. and itake valves are those little rods which moves up and down as seen in the vid i posted up. so yes VVTi is the valves opening on either the intake side or exhaust side to give better breathing which results in better acceleration. valves cannot stay open at all times becuase they need to close at some point to allow the engine to combust the air/fuel mixture.

Hi Disco stu can you please send me the link of how the dude managed to get his intake valves to open all the time?? its impossible to have intake valves open continusly during and engines operation because in order to have a combustion process, intake and exhaust valves need to close for this to happen. this process is known as the 'power stroke' this is where both the intake and exhasut valves needs to close so the spark plug can ignite the air and fuel mixed inside the cylinder.

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Im only on my mobile so cant post a link but if serch "lexus is200" on facebook you will get the group,if u just post and ask who it was they will reply pretty quicklu, might of been some1 called alexander :)

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noby i think he's talking about me, the acis valve i have mine disabled so i don't have to wait for the engine to reach 4500rpm, it feels like it all the time, (and no the intake valve inside the engine aren't open all the time, that would be a disastrous fail lol) also the lexus is200 doesn't have a VVT-i kick like the vtec kick in hondas lol i would of thought someone else would of figured this stuff out by now or i'm i just a true legend ;)

http://www.lexusowne...09

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noby i think he's talking about me, the acis valve i have mine disabled so i don't have to wait for the engine to reach 4500rpm, it feels like it all the time, (and no the intake valve inside the engine aren't open all the time, that would be a disastrous fail lol) also the lexus is200 doesn't have a VVT-i kick like the vtec kick in hondas lol i would of thought someone else would of figured this stuff out by now or i'm i just a true legend ;)

ahh that explains it then, most people get confused when they hear valve mistaking it to meant the engines intake valve. whilst forgetting the ACIS also has a valve which opens. so correct me if am wrong but are you not loosing even more low down torque by having the ACIS valave open all the time?? i was under the impression when this valve is closed at lower revs i.e from say 750rpm to 3500rpm it helps build up cylinder pressure becuse the air comming in is going through the long route in the tube which will mean more air because its taking the longer path to speed up the cylinder build process and once 3500rpm is reached the cylinder are charged up enough with air so the longer path is not needed and thats when the shorter path takes over by the valve opening up to inhale that rush of air. and i think it makes sense for Lexus to have it this way because lots of air is not needed at lower revs cylinder pressure is whats needed at lower revs and lots of air is rather needed at high revs. so by opening it 24/7 i beleive your low end torque will de affected drastically which will result in you even putting your foot further down to gain any speed at low revs but i might be wrong.

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Hi can you please tell me the address and how much it costs you for remap .Thanks

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My view is that the "extra air" is introduced through the inlet system, not the exhaust else all you would get would be a super lean mixtyre that would soon kill the cat.

If you have ever had the throttle valve off one of these motors you wilol know that there is a "built in" restriction to the inlet tract, this is usually to build up air speed to enable a better fuel droplet mix, the faster the air moves (up to a point) the more the fuel can wrap the air molecules, the problem of the air cooling down as it "grabs" the fuel is offset by the air speed causing friction.

Now I don't know the Lexus system completely, but I do know how the variable flap system works of the X type V6, it re-directs the air flow to get the best swirl characyeristics for any given throttle position, it's all controlled by the ECU and it's been done so well that no-one has managed to improve it yet even after these motors have been around in one way or another, in various Jaguar models since the mid 1990's. (S type, Xtype, XJ350 and now the Ftype) In fact the design was so good that Aston martin used a version of it for the V12 6 litre motor they put in the DB9. It's basically two Xtype engines linked together. Clever booggers.

The point being the Jaguar engineers got another 20bhp out of the V6 3.0 motor than Ford ever did with their version as fitted to the Mondeo ST220. the 220 being relevant here....

So, back to Lexus. It makes sense to restrict the flow to improve fuel/air mix, but at some point the restriction will kill the motor. No doubt Toyota's engine guys figured out the best time to allow more air in, at about 4,000 rpm by the sound of it... Before the injection phase obviously, no point putting more air in after the fuel has been added.

So anything that makes this extra port open would to me mean that there is a risk of weak mixture being introduced, because the motor only has one lambda, the ECU will have one 3d map to follow, and it will likely be unable to adjust the mixture quickly enough, I feel, to protect the engine. (Jaguar has two per cylinder bank, pre cat and post cat because it micro manges the mixture, it's why I can get 30mpg figures all the time).

So fuel consumption would probably tumble because to get the power back I would suspect that larger throttle openings will need to be used for any given engine load position. It's a cable throttle isn't it? Not fly by wire?

Anyone out there is trying to 2nd guess the Toyota guys who had unlimited budgets to get it right. You have someone with a laptop and bugger all testing facilities offering you a few tweaks to the already pretty good setup. I know who I would trust. Unless the tuner has some empirical data (as in proof of the pudding) I wouldn't believe them. Are you sure he hasn't just left the air filter out so that it sounds throatier? Very much doubt it's any quicker, 145bhp ish is about right for a 2 litre naturally inducted motor tbh. Even one that has more internal friction than the average motor. (two more main bearings, two more cylinders with pistons rushing up and down, two more big end bearings and con rods to start and stop). But it's surely a smooth lump.

BTW, the IS200 has to be fitted with the easiest air filter replacement system ever.

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