2021 Heritage Supercharger Experience

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Uh, yes, yes there are. If you look at the motor as simply an air pump, the fact that you're now forcing in much more air with forced induction is a critical difference. As is the fact that when you force in that air, more fuel needs to be added and timing needs to be taken away. Since the factory ECU hasn't a clue that that's happening, it won't be able to add enough fuel or take away enough timing.

Harrop, frankly, are clowns by saying it's ok to slap a supercharger on our platforms without the need for tuning. They're saying that because they don't have a way to tune it, if they did, they absolutely would be including one.
The factory ECU monitors airflow via MAF, so it absolutely does know what is happening, and it has been documented that the stock map covers airflow rates up to 140% of sea-level full throttle load with margin- in other words more than is required for 6 psi of boost.

MAF is Mass Air Flow, a quantitative measure of the mass of air flowing into the motor, which the ECU then sets the injector duty cycle to provide the appropriate fuel to achieve a target AFR.

Harrop acknowledges that the stock tune is sub optimal for performance in this application, but is over-optimized for detonation margin.
 
Hello all.. I am new here. I own a 21 Heritage and would like to install a supercharger. I know the TRD/Magnuson is no longer available. I am looking at Harrop. Does anyone have any direct experience with supercharging their 200 series? Thanks in advance..
I have direct experience of installing the Harrop kit myself. Other than a fit issue with the fuel pump provided in the kit (related to clocking of the housing on the Deutsch MotorWerks pump which Harrop quickly addressed) the fitment was easy- a little less involved under the hood than the TRD kit I fitted to an FJ some years back, but pulling the fuel tank to swap the pump was a pain.

Performance has been fine, no significant change to fuel consumption but I am constrained now to use premium fuel.

I admit most of the time the extra performance isn’t needed, but driving at altitude is now much improved (around Tahoe for example). Much better pull off the line if you give it the boot, and less hunting for gears on climbs though the cruise control seems to have a hard time accounting for the extra performance at times. The whine from the charger is only heard under boost and is pleasant.

I’m happy to connect directly if you want specifics on the install…lots of negativity here from those who haven’t been there/done that. If there are any known failures attributable to a Harrop charger install on a 3UR I’ve yet to hear about it…I’m all ears though.

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I think it's entirely credible that 6psi stays within the performance envelope of the stock fuel map. It may not be optimized for performance, but it's safe.

There's easily a 6psi delta in atmospheric pressure between say Black Bear Pass and Death Valley on any given day and this changes daily with the weather. This is why a plane's altimeter needs to be adjusted. The MAF does this calculation for us. There is also a 1-1.5 psi variability in the boost pressure for the same reason.

The Eaton SC Harrop sells as a kit has uprated injectors and fuel pump, intercooler etc. If it's able to maintain an AFR of 14-15 at idle/cruise -- and without going below 11 at WOT or 16-17 at the leanest -- while managing the increase in IAT, the MAF, O2 and knock sensors are going to be able to run the engine within acceptable margins.

If things start to approach the point of pre-detonation, the ECU is going to pull spark, resulting in a rich condition which cools the cylinder (and ultimately dissolves your cats), but Toyota has to build in margins for worldwide variability in fuel formulations/quality and there's room to play at those 87 octane margins. As long as you run 92+ octane, and no greater than E10 (as Harrop requires) you will see performance gains without risk of a short term catastrophic failure with a stock tune.

There is substantial risk however in trying to tune for performance beyond that with a piggyback Unichip-type controller. It is relying on sensor data to spoof signals back to the ECU and if it gets those calculations wrong, or takes out-of-range inputs from a bad sensor, and spoofs "everything's fine" back to the ECU, then, Boom!

I have a SC on our 7k-lb over-armored & underpowered 4sp 100 and if I ever feel the need to put a SC on the 200, I won't hesitate.
 
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The MAF can only read within a certain voltage. Once that voltage (ie, airflow) is exceeded than the ECU can no longer compensate. Adding a supercharger will absolutely max out the MAF reading and the ECU won't know what to do. It''s also unable to manage the timing maps.

So Harrop is adding larger fuel injectors and a larger fuel pump with no tune? So the ECU has no idea it has a larger fuel supply? Wow, this just gets worse and worse. The only reason they're not including a tune with this kit is because they can't make one. You know damn well that if they could, they would be. Them claiming that it doesn't need one is just bogus.

Look, everyone can make their own decisions here but to me, there's no way I'd buy this and install it on my 200. Simply put, it needs a tune to be able to run the larger fuel injectors/pump and handle the timing/fuel maps. Even with that overall reliability will still be impacted, you don't add forced induction and still have the same long term durability.
 
Im in the market and don’t really have a dog in this race one way or another. The 200 will leak all over and fail in various ways all on its own, so in that regard i’m not too worried. Slightly yes but not when the factory installed SC was a thing.

I am however waiting for the ECU unlock tune to come out for my model year. Otherwise im afraid to compromise long term ownership.

Of course, money is the only real issue here. A new engine is only $7500 right? Similar for new transmission? If i wasn’t trying to milk value out of this purchase I wouldnt even flinch to throw that kind of money at a rig that will give me decades of use. But that kind of goes against the ethos of my purchase here. Where i could be much happier in a Range Rover had I been willing to spend the coin to keep things running.
 
And as pointed out a) do you normally accelerate with your foot full down and need the extra HP? and b) the chassis/suspension/brakes for a Land Cruiser are not suited for BMW like driving anyways.

Ofcourse those who have excess money, allow passion to overtake logic and just want to hobby away should definitely get one.
 
The only reason they're not including a tune with this kit is because they can't make one. You know damn well that if they could, they would be.

Third.
 
O2 sensor banks monitor AFR. The ECU knows exactly what the fuel supply is.
And will adjust it to be ideal for natural aspiration, not forced induction.
 
O2 sensors don't work that way. Especially narrow band ones. You realize the ECU fuel/timing tables have limits, right? That no matter what the input is, it won't add more/take away than xxx, same with timing.

I know you don't believe me, but the factory ECU simply can't adjust enough to compensate for forced induction.
 
I know you don't believe me, but the factory ECU simply can't adjust enough to compensate for forced induction.
This is a philosophical discussion since none of us know the actual limits and margins of the stock tune.

I would argue however that Harrop, with nearly 70 years of performance engineering experience, does. Or at least they think they do, and they're confident enough in their data to bring a plumbing-only SC to market to exploit an 87 tune on 90+ octane. If the 3UR-FE was a premium-only engine there wouldn't even be a product from them right now to argue about. Could they be wrong about needing to tune it to sell it? Sure.

TRD pulled the Magnuson mill for the 2UZ-FEs because it didn't play nice with the 2003+ VVTIs. In fact TRD has pulled numerous superchargers off the market due to unanticipated reliability issues and this is a factory authorized tuner/upfitter. "Performance Engineering" by its very definition means moving the performance/reliability slider away from the reliability end of the range. It doesn't matter if that's aftermarket or factory forced-induction.

Software tuning and dyno sheets sell hardware, so I'll agree with your point that if they could tune and optimize it, they would, and I'll leave it at that.
 
Meh, I used to have oil change intervals on 2j's every 500 miles, or about as frequent as a new shortblock 🤣

I say shove 40 lbs of boost in there and report back with your findings. For science 🤭
 
This is a philosophical discussion since none of us know the actual limits and margins of the stock tune.

I would argue however that Harrop, with nearly 70 years of performance engineering experience, does. Or at least they think they do, and they're confident enough in their data to bring a plumbing-only SC to market to exploit an 87 tune on 90+ octane. If the 3UR-FE was a premium-only engine there wouldn't even be a product from them right now to argue about. Could they be wrong about needing to tune it to sell it? Sure.

TRD pulled the Magnuson mill for the 2UZ-FEs because it didn't play nice with the 2003+ VVTIs. In fact TRD has pulled numerous superchargers off the market due to unanticipated reliability issues and this is a factory authorized tuner/upfitter. "Performance Engineering" by its very definition means moving the performance/reliability slider away from the reliability end of the range. It doesn't matter if that's aftermarket or factory forced-induction.

Software tuning and dyno sheets sell hardware, so I'll agree with your point that if they could tune and optimize it, they would, and I'll leave it at that.

But what about an LX on a factory 90+ tune? They sell it for that platform, and I’m not sure how that is supposed to pan out. This is yet another hot topic of running regular for the LX. No one has been able to determine the mapping differences between LC / LX 3UR tuning that I’ve seen.

I get that harrop is reputable and I’ll probably end up throwing my cash at them because life is short, but they dont know either at this point.

It would be nice to get some data for the older 200s, those with proper tunes so some of you guys can break it down for ppl like me, itching to waste $8k.
 
Harrop have actually done the engineering work to evaluate the response of the stock ECU and then published their data.
The MAF can only read within a certain voltage. Once that voltage (ie, airflow) is exceeded than the ECU can no longer compensate. Adding a supercharger will absolutely max out the MAF reading and the ECU won't know what to do. It''s also unable to manage the timing maps.

So Harrop is adding larger fuel injectors and a larger fuel pump with no tune? So the ECU has no idea it has a larger fuel supply? Wow, this just gets worse and worse. The only reason they're not including a tune with this kit is because they can't make one. You know damn well that if they could, they would be. Them claiming that it doesn't need one is just bogus.

Look, everyone can make their own decisions here but to me, there's no way I'd buy this and install it on my 200. Simply put, it needs a tune to be able to run the larger fuel injectors/pump and handle the timing/fuel maps. Even with that overall reliability will still be impacted, you don't add forced induction and still have the same long term durability.
At some point you can max out the MAF reading. Harrop selected a drive ratio for the Stage 1 kit that does not provide enough airflow to max out the MAF.

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This is a philosophical discussion since none of us know the actual limits and margins of the stock tune.

I would argue however that Harrop, with nearly 70 years of performance engineering experience, does. Or at least they think they do, and they're confident enough in their data to bring a plumbing-only SC to market to exploit an 87 tune on 90+ octane. If the 3UR-FE was a premium-only engine there wouldn't even be a product from them right now to argue about. Could they be wrong about needing to tune it to sell it? Sure.

TRD pulled the Magnuson mill for the 2UZ-FEs because it didn't play nice with the 2003+ VVTIs. In fact TRD has pulled numerous superchargers off the market due to unanticipated reliability issues and this is a factory authorized tuner/upfitter. "Performance Engineering" by its very definition means moving the performance/reliability slider away from the reliability end of the range. It doesn't matter if that's aftermarket or factory forced-induction.

Software tuning and dyno sheets sell hardware, so I'll agree with your point that if they could tune and optimize it, they would, and I'll leave it at that.
If they could tune it, they would. They would be able to achieve more HP and charge more money. But instead they can sell a safe power increase that isn’t super efficient. But the margin discussion isn’t philosophical- Harrop have evaluated the response of the stock ECU and published their data. Now you might argue that they could say anything to make a buck- sure, maybe…but they have a reputation to uphold and I doubt they would deliberately sell a product that would grenade a motor. Read for yourself here: https://harrop-usa-website.nebhub.c...usa/TG_190808_Toyota_3UR-FE_V8_Tech_Guide.pdf
 
I don't doubt the 3URs ability to withstand additional load from a supercharger, but I will definitely wait until there is a tune available for my 2019 before proceeding. No one is talking about the transmission though. I'm not thrilled at the idea of replacing it every 75k mi or so.
 
What’s the difference between 5psi of boost when driving at 7000 feet and driving with full throttle at sea level?
The difference is Toyota is aware we don’t need the ability to drive our vehicles at 7000ft below sea level.
 
In general I hate to weigh in here because no one is going to change their mind.

The only reason that I'm posting is because of ignition timing. Harrop tested with the equivalent of 93 Octane. If you can get 93 regularly, great. I can't. Harrop states that with 93 and boost knock is equivalent to 87 NA. Meaning that knock is present and timing is being pulled. I've done tunning on a heavily modified 3FE and am pretty comfortable with Harrop's approach to fueling. However, I'm not willing to ride the knock sensors more than Toyota intended.
 

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