ndk83

A CL member has installed this on his IS250 in Singapore, ITs not listed on the TOMS Japan, US, UAE website, but the product is offered in Singapore and Hong Kong

I would have thought it should be engine/ECU specific but frmo the website:

The website doesnt list specifc models for each car, rather its one thing

Can this thing actually work gains wise??
What would b the benefit of installing this, and being able to control how lean/rich u ran ur air fuel mixture.???

How does this relate to compression ratios? (My second gen IS300 has lower compression than an ISx50)


Lets hear everyones thoughts and opinions

MRxSLAYx

Very interesting. If it actually does what it says it does then it when used correctly it will work. Remember leaner is meaner.

ndk83

Here are the websites for anyone that is interested

http://www.toms-trd.com.hk/eng/main_...contentid=7774

http://www.tomsracing.com.my/

Lets Drive

iTrader: (3)

From what it looks like, it modifies the signal from the MAF sensor to the ECU, which then compensates by adjusting the AFR. Depending on the setting, this will either richen things or lean them out.

I'd say in theory, some work, but the money is better spent elsewhere. Besides some other input factors, turning a dial to adjust fuel maps can be tricky, possibly leading to detonation. There are also some other adjustments and parameters that should be taken into account when properly trying to adjust AFRs.

The compression ratio is unaffected by this device, as that has more to do with the volume within the cylinder, not so much the balance of fuel being injected when discussing the A/F mixture.

ndk83

So running richer will maximize fuel efficiency(?) and running leaner will maximize engine performance(?).

Basically my question is this :Is there engine performance to maximize?

I remember during the mazzuri headers thread for IS350, not being able to control the fuel ratio was a reason why there werent significant gains. My memory on the subject is rusty but i remember something along those lines
.
In stock form will our engine benefit (in performance terms) from adjusting the ratio? (theoretically yes) but will this actually happen? wat are the factors that determine its effectiveness?? Do our stock cars run rich or lean? Id assume somewhere in the middle but i hear toyota lexus vehicles run rich.

ndk83

on the Estima forums in malaysia, one guys said his buddy installed this on a 3.5L and got gains of around 20bhp with a dyno (atleast thats what i think it says). dunno if i believe that... hell if this thiing can deliver up to 5hp ill b satisfied, thats 5hp more than any other performance mod.

http://f1-0.com/index.php?topic=869.0

badx33

iTrader: (53)

HOW much this cost?

Kurtz

iTrader: (1)

If it's just lying about what the MAF sees to lean the fuel mixture it'd "work" just like any other AFC would "work" for about 50 miles until the feedback from the O2 sensors tuned its changed back out.

Probably gain you 5-7 hp at the track for a bit, useless for daily driving unless you wanna reset your ECU every 50 miles.

And as noted just having a **** is a pretty risky way to tune your A/F mixture.

ndk83

Do all modern Toyotas (specifically the estima) have o2 sensors?

Is there anyway around this?

wouldnt the fact that its manually adjustable override the ecu ever learning? hence once the ecu adjusts, change the setting. (running rich-ish most of the time, and lean only when u wanna have a bit of fun) or would have to reset anyway?

Kurtz

iTrader: (1)

Can't speak for oveseas cars... but ones in the US have been using O2 feedback/closed loop mode for, I dunno, 20-30 years at least?

The way the system works is this:

The MAF (and IAT) read the volume and temp of air coming in.

The ECU has maps that say "Under these conditions, for X amount of air at Y temp, inject Z amount of fuel"

The O2 sensors read how rich or lean the result was, and this feedback changes the short/long term adjustments the ECU makes to its maps.

It's got targets for rich/lean though, and it's constantly adjusting the maps to hit those.


So if you use a device that lies about how much air came in you can get it to lean the mixture for a while, but eventually the O2s telling it "nope, that last batch was lean too" will cause it to add fuel back in till it hits its intended targets again.

There's ways around this, but they're pretty complex (Gernby had a piggyback for while he was planning to make trick the O2s as well, but I don't think he ever finished the project as it would've been too complex/expensive to sell commercially)

ndk83

im not sure if im not understanding you, or your not understanding my question:

I get wat the afc does, and how the O2 will tell the ecu to readjust,

but since the afc is adjustable, cant u just change it to rich(if u were running lean) and re confuse the ecu and o2 all over again without having to reset it?

or just figure out how long it takes for the ecu to adjust, leave it at at the stock ratio, only using lean for spirited driving when the need arises and change it back to stock ratios before the ecu can adjust?

Lets Drive

iTrader: (3)

It's not as binary as this. You'd need to somehow monitor the AFR, via data logging or some other means, or run the risk of detonation, depending on the specifications offered by the AFR controller. If not, you'd pretty much be shooting in the dark for when and where you need to adjust, which again, gets tricky.

So long as the ECU is aware that it isn't running the proper AFR (for performance, emissions, and fuel savings reasons), it will be a back and forth game, which is why I think its not worth the money.

In theory, you could, but again, even with proper monitoring or logging of your AFRs, it becomes tedious, especially on a street car.

Not to discourage, but in spirited driving, the amount of performance you'd get from this would be negligible for the effort, IMO. I'm thinking you could get closer to the limits of your IS just fine, and not miss the difference.

ndk83

Thanks for taking the time Shinobi/Kurt to answer my questions, u really made me aware of how potentially dangerous and/or useless it could be.

Nevertheless, the quest for more power sometimes overpowers logic and common sense...

so

Hypothetiaclly, if proper testing and data logging is done. and hopefully since this product is assosicated with TOM'S, their afc tuning would be conservative and wont ruin my vehicle, then their could be power to be gained. Even if temporarily.

Will the car continuously have to be monitored? How often are we talking here?
I know im probably over simplifynig the issue but is it possible that this afc will be a mild tune and not require continuous data logging?? Maybe a one time (or several time initial) test to see how lean or rich it runs at the extremes?







I know its stupid, but my car is underpowererd. I love my IS, we dont have 350's and F's here so this is all i got. Exhaust made the car sound bettter, lighter wheels made the car go a bit faster. I cant even get an Intake for my car, so to me this 5-10hp will b very much worth it, esp if you can feel it.
The CL member who has it on his 250 confirms that their are gains (via the notoriously effective yet highly inaccurate butt dyno)


Im gonna continue researching the crap out of the subject, til i make up my mind. Right now its 60/40. The right side of my brain says jump on it right now wats the worst that could happen, while the left is telling me; dont b a fool.

Kurtz

iTrader: (1)

People also insist they "feel" gains from many other things that measurably provide none at all.

No human on earth can "feel" a 5 hp gain on a 200+ hp car.

As I said, AFCs have been run on 350s (Jeremy used one I believe) and gains were barely above that (~7 hp on a 350, so should be less on a 250)... and of course the computer tunes the gains back out after 50 miles or so, he only used it for the track.


In theory you COULD do the following-

Hook up datalogging equipment to monitor the car
Hook up an AFC
Lean the car out to gain your 3-5 hp on a 250.

Now, the ECU will notice "Huh, I'm running leaner than I should, better add more fuel" and you'll lose that 3-5 hp after maybe an hour of driving.

Then you can lean it further with the AFC

Now, the ECU will again notice "Huh, I'm running leaner than I should, better add more fuel" and you'll lose that 3-5 hp after maybe an hour of driving.

Then you can lean it further with the AFC

And so on, and so on... eventually you will exceed the capacity of the ECU to add any more fuel to the system, and your 3-5 hp gain will stay.

That's the good news.

The bad news is if you ever -actually- run any more lean than just your AFC adjustment for any reason (and there's many reasons that can happen) you will damage your engine because the ECU is no longer capable of enrichment of the fuel mixture to protect the motor.

That seem worth 3-5 hp to you?

(And well before that you might well trigger a CEL because the ECU thinks "There must be something wrong if I'm having to dump THIS much extra fuel ALL the time" and have that to deal with as well)

mikes rx

iTrader: (14)

^ Don't forget about CL member Gernby, who set up a piggy-back ECU......

https://www.clublexus.com/forums/per...mp-on-2is.html