Ive been waiting for this, ive been checking the facebook page for updates, one week to go, good luck,

 

50hp isn't actually out of reach. Bimmer boys get about 30hp from headers.

 

Yeah! That's only 66% more than a car that responds astoundingly well (for its displacement) to headers!

Don't get me wrong, I hope there will be gains - and there probably will be... but who's to say the stock ecu can even learn how to make 50 more hp? how 'bout 30? 10 even? How much control does it have over timing and fueling? How much fuel flow do the injectors support? The fuel pump? Maybe adding an intake and an exhaust already push the ecu to the limits of its learning envelope, and anything beyond that it just can't figure out. What EVERYONE on this board who is serious about tuning should do is contact a company that has the potential to create a tuning device for these cars. http://www.cobbtuning.com/ and ask them, no BEG them to come out with a product for the 2IS.

Didn't mean to get off topic, but really - it's in the best interest of the OP if someone gets some tuning software/hardware for these cars - that's when modifications are really going to shine.
/rant

 

They really, really, really aren't.

TOMs in Japan can tune the 2IS ECU...they do so for their Supercharger kit. It adds a very small amount of additional performance (and part of that is the fact it's programmed for 100 octane fuel).

I dunno what magic people thing "programming the ECU" is going to accomplish.


And FYI, the LMS supercharger kit in the US for the 2IS uses the stock ECU, so it's obviously got enough inherent adjustment it can add fuel for 5 psi more air (or about 40 rwhp).

The ECU isn't the problem. The fact it's an NA, 12:1 compression, already-very-well-designed-engine is the problem.

 

I could have sworn the IS350 engine is 11:6 and the IS250 is 12:1

 

No offense - but 40whp could easily be within the learning margin of the car - most ecu's can handle fluctuations around 15% in power - want to guess what percentage 40whp is of 270? Just a guess, but I'm guessing the (defunct) LMS stopped adding boost when they stopped gaining power... because the ECU couldn't handle any more...?

 

Then you'd guess wrong. They stopped adding boost because they didn't want to damage the stock-internals high compression engine.

As I said, TOMs in Japan can program the ECU (JDM spec ECU, not US spec), and their supercharger makes a whopping 10 extra horsepower and needs higher octane fuel to do so. No amount of magical programming is going to permit you to run massively more boost on a high compression engine with the stock internals... some kind of added injection (meth/alky/water) might get you an extra couple pounds (at added cost and complexity) but that's about it.

The fact 40 hp is in the learning margin of the car was my basic point to you though, since you are the one who in your very last post asked if the reason we don't see more gains today is because we're at the limits of what the ECU can do on its own with intake and exhaust, and clearly, we're not.



To iSuxeL- the 250 is 12:1, the 350 is 11.8:1, which is close enough to 12 as to not make much difference for power adders.

 

How is it clear that you're not at the limit? Who has made more power on the stock ECU? I can easily believe that 40 hp is within the limit of the stock ECU - that 15% is fairly standard for most cars - hell, the IS might be capable of 25% - my point is that there is a definite limit to the ECU's ability to learn - Lexus did not equip these cars with a magical ECU that knows and understands all - nor did they equip the car with a fuel pump or injectors that could handle 600whp, most likely not even 300whp. There IS a limit to the learning ability if the stock ECU, and there ARE gains to be had from:
A) raising the rev limiter (duh)
B) Adjusting timing and fueling
I'm not saying that there will be a magic box that someone can sell to make this happen - I'm saying that someone needs to find enough fiscal initiative in decrypting the ECU of these cars to make it adjustable.
I'm not pissing in your cheerios - not even your corn flakes. I'm just saying that adjustability (not necessarily by the end user, but by a qualified tuning shop) would be preferable to bolting on a product and letting the lexus engineers' thoughtful provisioning guide you(I'm sure they meant you to put a cold air intake, remove the cats, put high flow headers and a cat-back exhaust on their car and have it perfectly adjust itself to the new modifications...they're just magic like that).

 

I'll seperate the points more clearly, since you seem to keep missing them:


you suggested the car might already be at the limits of ECU learning with just intake and exhaust (about 15 hp).

I explained you were wrong by pointing out it handles 40 hp with the LMS kit.




you then suggested that clearly 40 hp might instead be the limit since that's when LMS stopped and huge gains might be had past that.

I explained that was wrong too, since TOMs in Japan -does- have access to the ECU and they make their own supercharger kit, and they still barely made any more power than LMS did.



There's simply very, very, very little to be gained by playing around with the ECU. A few folks have used piggybacks to trim the fuel and seen gains in thr 5-7 hp range (the ECU tunes this back out after a while if it's not a feedback piggyback, but even editing the ECU wouldn't gain you more here than they get temporarily.

TOMs only gets 10 extra hp with their supercharger kit AND ECU work versus just a supercharger.

The ECU ain't what's holding the car bar. The fact it's 12:1 (or 11.8:1) and already very well tuned and designed is why it's not being held back much, there's just not a ton more there with stock internals.

 

OT: Thats why people need to start making headers superchargers for the 2nd gen IS300. We got different internals, we dont have dual port injection and we have a much much lower compression ratio. our 3gr-fe engine also seems to be detuned.

Its such a shame that our market is very small and not profitabe for tuners

 

Correct me if I'm wrong...

But i thought that the Stock Ecm handles 6psi of boost. This is the same for the Is250/350 and F. The problem is that the 350 only makes 40whp on 5psi... Not that the motor can only handle 40whp.

After reading a few pages in this section, i personally think that the best setup for an is350 is going to look something like this:

Intake
Exhaust(including Headers)
N20

 

A couple folks have run N2O with decent results as I think I've mentioned before... (50-65 shots on pump gas, and a whole like cheaper than any FI setup, though not always on of course)

There might be some whacky combination of modifications (intake, exhaust, headers, forced induction with additional alky/meth/water injections, then N2O on top of all that) that gets you maybe, almost, just a little bit short, of what a stock IS-F puts out.

Or for probably the same or less money you can just buy an IS-F instead of a 350 and have that power stock, reliably, and under warranty...with a vastly superior behavior transmission.



Now, trying to get back to the actual topic of the thread... if someone can manage to beat Mazzuris gains of -1 horsepower with IS350 headers, great... even better if they can do it with a set that's affordable and will actually pass a visual smog inspection outside of CA (ie it'll still appear to have cats on it).

Given the numbers of folks who spend $1200+ on exhausts that add 7 hp (some of the pricier axle-backs) I'm sure there'd be folks lining up around the block to buy headers that did any better.

But you're dreaming if you ever expect to get huge numbers out of mods for this car for any reasonable cost... N2O is as close as you're going to get, and you best know what you're doing if you plan to go that route... and "unlocking the ECU" isn't going to change that because it's not the ECU that's holding much back now... it's the fact it's a high-compression NA engine that's already fairly well designed from the factory. This isn't an old chevy V8 where they grabbed random unmatched bits from the parts bin and decent aftermarket parts can add hp for pennies.

 

I agree that the compression is holding back the car's potential for adding air and fuel, but it doesn't follow that there aren't gains to be had from the ECU.

And I also agree that that the car is obviously well designed from the factory, it has a good specific output and quality parts. HOWEVER, aren't the engineers at Infiniti/Nissan, Subaru, Mazda, Mitsubishi, Honda, BMW, M-B, etc. all at least similarly competent? The facts are in evidence that ECU modifications on these cars provide ample gains - at least as much as a '1200 dollar exhaust' for significantly less - yes I agree that this isn't an old chevy that can be quickly improved on the cheap, but is Lexus really that much better at making cars than any other manufacturer? Did they make the car with an innate ability to perfectly suit itself to something that gets bolted onto it?
My point is that there is still *some* potential left in the car that isn't being utilized by just bolting on a new part. No one makes a product for these cars because they don't see a market interest in it - they're not going to make a product without a consumer base. We're on the same side here, we want more improvement for less money - it's about hp/dollar, and ECU modifications have proven in other similar cars to be a good value.

Again, sorry to the OP for derailing the thread, I'm also eagerly awaiting and hopefully expectant of good results.

 

I'm sure there's a good 10-15 horsepower in the ECU. As evidenced by the fact TOMs, with ECU access, doesn't get any more than that out of it, and the folks who've done some fooling of the sensors via SAFCs get about half that.

But that's probably not worth a company risking a DMCA lawsuit from Toyota by offering a commercial product that cracks their encryption.

From what Lobuxracer has posted nobody has still even cracked it on a supra, a car for which I hear there's a bit of an aftermarket. Thanks to being a much less complex system though there's some aftermarket engine management options there for the modders at least, less so here (and much less reason for them too with no FI options).


Which models? A whole lot of the makes you mention have models with forced induction on them... where simply increasing the boost (via ECU or not) is an easy power add.


IMHO yes...that's one reason I own one.

We've already establish the stock ECU is more than capable of handling considerably more power than all the normal bolt ons currently available for it. What exactly do you think an intake does that any decent MAF/O2 closed loop system can't adapt too easily and quickly? Or an exhaust for that matter.



No, they don't make it because toyota encrypts their systems, and it's REALLY HARD to break that (and potentially illegal thanks to the DMCA). On top of that, gains are likely to be quite small given everything else we know, including the fact that in Japan where they DO have ECU programming the gains are... small.

As you note there's other cars where it's easier and the gains are bigger, so better to focus ones business there.

 

I don't think the DMCA applies to this specifically - Cobb cracked the Nissan GT-R ECU (big hooplah about how nissan made it un-crackable to cut down on aftermarket modifications that were so prevalent in previous skylines). The GT-R and IS are apples oranges, obviously, as you stated. But Cobb also offers products for the Infiniti G35/37 and 350/370Z. I think these would be fairly similar in terms of gains. Again, it's not just about re-writing the ECU on a stock car, but maximizing EACH car with the mods it has.