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Discussion Starter · #1 · (Edited)
Given that it is possible sooner or later people in the US will have access to an aftermarket ECU software upgrade and (hopefully) Australia at some point as well, it begs the age-old question of how far you can safely push the 2ZR-FAE / 2ZR-FE engines whilst still keeping within "safe" original factory design tolerances and also meeting the strict emissions laws, maintaining excellent reliability and durability with minimal servicing intervention apart from routine scheduled maintenance.


I find it interesting that of the real sporting car companies that use Toyota engines today, Lotus stands out well and truly above all others. Yet what confounds me somewhat is that despite the overtly sporting base model Lotus Elise using the 1.6 litre version of the Scion iM engine (1ZR-FAE), they only squeezed between 2 and 4 hp more out of it compared to that engine's implementation in the bog-standard Toyota Auris (and in the same country - the UK - so subject to precisely the same emission controls).


Elise Sport | Lotus Cars


The stock Toyota engine when it used to be put into the Auris put out around 130 hp. And there is no difference to the torque output in either implementation.

So I have to ask the question: why such a tiny power increase? Even though Lotus is obviously all about the light weight, the chassis and the balance, don't you think that even so, if they'd managed to get 150 hp out of that engine, they would have? I can't see any reason why they wouldn't. It's not like it would end up competing with any other Lotus since the next step up to the 1.8 litre model is quite massive - the supercharged 2ZR-FE. Yet something like a 150 hp output would make that engine commensurate with the power increases all the aftermarket tuners would get with this sort of engine (which is usually around 10 - 15% for a normally aspirated engine).

This being the case, I can't help thinking that these Toyota engines are already pretty much pushing themselves to the safe and legal limits, whether that be long term durability, emissions, etc, etc. Furthermore, if I look at the best little normally aspirated Toyota small cars of recent years (say the 1ZZ-GE Corolla), there seems to be this "safe" torque limit of around 134 ft. lbs (around 181 nm). Effectively what we are measuring there is the maximum size of the "bang" inside each cylinder that the engine can tolerate. Power of course is determined by the rate at which the engine can produce those "bangs". It does sort of make sense that you design a cylinder head, engine block, pistons, etc to withstand "X" amount of explosive force within each cylinder until you get to the point where the long term implications are unsatisfactory. Our engines in their stock form are (depending on the country), maybe only about 4% below that limit - something that I would not question in a decent stock engine in a decent stock car.


Then on the other hand we have the 2ZR-FE in the Lotus Elise and that has a supercharger, massively boosting torque and considerably improving power. Yet so far as I can ascertain, there are no changes to the internals of the engine. That said, it seems that if you go to Lotus forums and browse Lotus servicing related-sites and videos, engine maintenance and mini overhauls are almost a ubiquitous deal. I saw once a video where there was literally a bin full of camshafts. These are not high mileage engines either but they were significantly boosted over what the stock Toyota engines produce.


So I have to pause when I think about aftermarket tunes. To me, something like a 15% power increase is a bit over the top in 2016 when there are so many strict requirements to adhere to. Something more like 5% sounds reasonable and it is what you'd likely achieve if you extrapolated an improved torque curve (to 181 nm) as previously described over the permissible rev range. If you hypothetically say that torque can be boosted everywhere by about 4%, then at the redline you'd maybe around around 6 to 8 hp more - something that sounds realistic and would actually be noticeable by any reasonably astute, regular driver. And on the subject of emissions, when I asked a company straight out if the tune would satisfy emission requirements, they suddenly stopped replying to me. Funny that.


In any event, I am going to watch the aftermarket tunes for the latest 2ZR-FAE / FE with interest, particularly as regards people's experiences with them. I have no doubt you guys in the US will get access to tunes long before us in Australia (if we ever do here which is a little doubtful). You guys have a much larger market so the effort that goes into a tune is well rewarded financially. Here in Australia I doubt there would be more than 200 people ever wanting a tune on their Corolla!!
 

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Unless you know something most of don't, I'm not confident there will be any after market tune. Except in cases where a piggyback or standalone ECU is used. I just don't trust that any company has been able to succeed on this engine, any engine, where the only ones to do it previously was TRD. They had to break all of Toyota's rules and hire the guy that designed the ECU in the first place. Who were you talking to about it?

I definitely won't spend real money on a few HP. If I do it, it'll be the real deal but it's too soon to build the engine, yet.
 

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I don't know much about this engine, but do know a bit about tuners, having had them on previous cars.

- Some ECU's are hard to make tunes for. Some manufacturers really make it difficult for aftermarket tuner companies to do their thing. (Not a programmer so I don't really know what the details are)

- Some tunes are better than others. Depending on the engine, the HP/Torque gains vary widely. Some engines are already highly tuned to the limits and you are lucky to get 2-5 HP. Others I have seen get 10-15 HP just by plugging in. Again, I don't have experience with this engine, but its high rev suggests there is not much left.

- It is really easy to mess up an engine with a tuner. Especially when you start getting deep into the program, I have seen engines go boom, (well at least the aftermath.)

- Warranty issues. Some ECU's come up red flagged right away when you go in for service if you have applied a tune, even if you "return to stock." Others are better at hiding tunes so you don't get flagged. Most warranties will be void if they see a tuner has been used. Use carefully if keeping your warranty is important to you.

- The one year run for the Scion iM. I know the iM will continue as a Toyota product, but I don't know if there will be subtle or massive ECU changes. Also, don't expect to be able to just pick up an Auris tuner, it's not going to be universal.

- The iM is not a powerful car. Those obsessed with performance hatches are going to go for the GTI or Focus RS which have engines almost double what ours have. Then those of us who are willing to purchase a tuner for an iM are going to be an even smaller group.

- Unfortunately, I think putting out a tuner for the iM is going to be a low priority for tuner manufacturers. I would love to see one come out, but I am not expecting one anytime soon.
 

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Discussion Starter · #4 · (Edited)
Unless you know something most of don't, I'm not confident there will be any after market tune.
There is already an aftermarket tune available for the Australian version (ZRE182 and ZER172) equipped with the 2ZR-FE engine and it uses the existing stock ECU without any piggyback. It gains about 10% to 15% power depending on whether the owner's preference is biased towards economy or performance. The reason I am not considering it (and the reason I would recommend people stay away from it) is because it is a bench tune only. That said, having spoken to the retail provider involved, the company that provides the tuning tools, base generic tune and is responsible for breaking the manufacturer encryption (Alientech in Italy) are working on providing that very same tune via the OBD port, but only available at an authorised dealer's premises. Further to that, however, it is possible that tune will also progress all the way to a DIY tune - in other words the owner can program the ECU themselves using a hand-held device at home.

The way this all works is that Alientech provide a generic tune after which their representatives in various countries provide enhancements and a configuration specific to that country's vehicles. So here in Australia, Alientech provide a generic tune for the ZRE182 Corolla and RDTechnik Australia will "Australianise" it. After which the tune is available from retail tuning suppliers.

That is all I really know at this point. I won't be following up with any companies here in Australia unless I see an update to the Alientech vehicle master listing that indicates at least an OBD tune is available. But as I say, it may never happen as an OBD tune but it is an irrefutable fact that any owner of a current model Corolla in Australia can get a tune if they are prepared to have it as a bench tune:

World class Engine ECU and Transmission TCU flash tuning, piggyback and chips. RDT Box, Shift Shift Plus tune for Performance, Economy, Power and Torque.

I cannot speak for companies such as Orange Virus in the US but I strongly suspect they are working with the same tools from the same company that companies here in Australia have. That being the case, it should just be a matter of time before some sort of tune is available for an iM, though again, Alientech calls the shots in terms of encryption via the ODB port, etc.
 

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Discussion Starter · #5 · (Edited)
- Some tunes are better than others. Depending on the engine, the HP/Torque gains vary widely. Some engines are already highly tuned to the limits and you are lucky to get 2-5 HP. Others I have seen get 10-15 HP just by plugging in. Again, I don't have experience with this engine, but its high rev suggests there is not much left.


Having looked at the sort of performance of Toyota twin cam engines over the last 30 years (4A engines and subsequent derivatives onwards) and more specifically torque output as it relates to engine capacity, I think there is room for improvement without upsetting intended engine lifespan or serviceability, but not a whole lot. But enough to make it worthwhile and noticeable.


I did some spreadsheet calculations today and came up with a realistic figure of the Australian version of the current Corolla going from 103 kw stock (138 hp) to around 108 kw with a tune (145 hp). I base that on the maximum production torque I have seen from a stock NA Toyota 1.8 litre engine and the anticipated torque curve that would result if torque on the production 2ZR-FE was beefed up across the rev range accordingly.


But that is below what the tuners are claiming which was basically why I started the thread. I think there is a case to answer that they may be pushing things a bit further than what is possible, whether it be because it compromises long term durability, serviceability, emissions or some combination of those factors. I could be wrong and maybe these engines are actually good enough to give 10 to 15 percent but surely it could only be with the highest octane fuel available in the target countries. Afterall, you can really only play with timing here since there is not a whole lot you can do legally with getting more air in the engine and getting gas back out (thus significantly changing AFRs). And changing those things (intakes and exhaust) really only improves throttle response - not outright performance per se (assuming you want to stay legal with noise emissions).


Every standard fuel car I have ever driven in the last 30 years has audibly pinged on standard fuel under load (mainly lower revs at high throttle openings with aircon on) - which nevertheless means they have their stock timing advanced right to the limit for standard fuel. Here in Australia 98 octane versus standard 91 octane is worth roughly 3 kw per 100 kw of stock power in an NA engine so long as that engine is specifically tuned for it. So if you take my spreadsheet calculations and independent testing of NA engines on our various fuels, I can only really see about 108 kw as being realistic for our 2ZR-FE without then infringing on emission laws.


I feel the situation would not be that different in the US. The only other ways to really increase power is to increase revs and I do not think the engine would really be happy much past 6,600 RPM given it lacks such niceties as forged conrods and other beefed up internals, etc.
 

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Thankfully, the noise and emissions laws are only strict in a few places in the US. Outside of California no cop is going to pull you over just to check if everything on your car is approved by one environmental agency or another. Even annual smog testing is limited to major metropolitan areas. I have no such limitations where I live. Only that the car meets regulation when it is sold new. So, they have a fairly large market here. Not sure I would care if there were limitations. I generally do what I want and pay the fines later. :D

I've only heard that Orange Virus is attempting to crack the ECU and may be making progress. Haven't heard much out of them lately but I'd buy something from them just to show my appreciation for their skills if they actually get something done. Haven't heard of the other company at all. I still don't believe either of them until it happens. But by then I'm no longer looking for a 15% increase on a stock motor. Once my warranty nears it's end I have the cash and the tools to get a minimum 100% increase on a built motor. But if they can open the ECU it would definitely shave $1000 off of the tuning bill.
 
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