Cables!
VF Tuner ECU/TCU Tuning for the GX550
- Thread starter VF Tuner
- Start date
- Thread starter
- #62
Hey everyone. Everyone should have tracking #s now and kits are on the way.
A few folks have sent us their ECU readouts.
I'd like to take a moment to discuss lexus "premium rquired" tune vs the Tundra 87 octane tune.
Some interesting info to ponder about. All of this information is comparisons of stock tunes.
While we have tuned this calibration and did bench testing, we didn't "deep dive" into comparisons over the Tundra before. We want to share some of this information now as we do some comparisons.
Reviewing The tune on the lexus, the only thing that stands out as why it*may* require premium fuel is that under certain scenarios (when all temps are in check, oil, IAT, ECT, etc) the ECU may allow as much as 1~2psi increase around 2000 RPM vs the Tundra.
However the Tundra runs more boost overall, especially at higher RPM.
BOOST:
The Tundra and the GX550 run nearly identical boost pressure and airflow limits. The GX550 does not get any "significant improvement" in boost pressure compared to the tundra. The GX550 can, in certain scenarios only, run slightly higher boost pressure at low RPM (around 2000 rpm) and about roughly 1psi higher than the tundra.
However, the GX550 actually gets LESS allowable boost pressure above 4400 RPM than the Tundra Does. Above 4400 RPM the GX550's boost pressure is gutted.
Ignition:
Ignition timing strategies and target ignition are virtually identical, except that the Tundra actually uses more low load / low RPM ignition than the GX550 does.
Valve timing:
Nearly Identical, with the exception being the Tundra has better Valve timing targets at higher loads / moderate load / above 4400 RPM or so.
We have not received much inquiries about making an 87 octane tune for this vehicle (even though we will be providing one).. VF Tuner is quite confident we will be able to provide you guys a solid 87 octane tune that not only is safe, but will provide you more power too.
This is just our opinion, but Lexus is requiring "premium fuel" for their "premium GX550" which actually does not need it. What is more interesting are the rumors that the GX550 uses a slightly smaller turbocharger than the Tundra, and lexus makes nearly identical power figures as the tundra, but requires premium, and uses less boost at higher RPM. This is very interesting. The lexus version does use lower ignition efficiency targets which would allow but not guarantee more ignition could be given (where power can be increased or decreased pretty easily).
Our opinion of the strategy: use premium fuel, Generate similar to, or slightly higher boost psi than the tundra at very low RPM, and dramatically reduce boost pressure in the higher RPMs while using an ignition strategy that calculates as "less efficient" allowing for more ignition timing at higher RPM.
The Tundra just does this easier and doesn't require premium fuel.
A few folks have sent us their ECU readouts.
I'd like to take a moment to discuss lexus "premium rquired" tune vs the Tundra 87 octane tune.
Some interesting info to ponder about. All of this information is comparisons of stock tunes.
While we have tuned this calibration and did bench testing, we didn't "deep dive" into comparisons over the Tundra before. We want to share some of this information now as we do some comparisons.
Reviewing The tune on the lexus, the only thing that stands out as why it*may* require premium fuel is that under certain scenarios (when all temps are in check, oil, IAT, ECT, etc) the ECU may allow as much as 1~2psi increase around 2000 RPM vs the Tundra.
However the Tundra runs more boost overall, especially at higher RPM.
BOOST:
The Tundra and the GX550 run nearly identical boost pressure and airflow limits. The GX550 does not get any "significant improvement" in boost pressure compared to the tundra. The GX550 can, in certain scenarios only, run slightly higher boost pressure at low RPM (around 2000 rpm) and about roughly 1psi higher than the tundra.
However, the GX550 actually gets LESS allowable boost pressure above 4400 RPM than the Tundra Does. Above 4400 RPM the GX550's boost pressure is gutted.
Ignition:
Ignition timing strategies and target ignition are virtually identical, except that the Tundra actually uses more low load / low RPM ignition than the GX550 does.
Valve timing:
Nearly Identical, with the exception being the Tundra has better Valve timing targets at higher loads / moderate load / above 4400 RPM or so.
We have not received much inquiries about making an 87 octane tune for this vehicle (even though we will be providing one).. VF Tuner is quite confident we will be able to provide you guys a solid 87 octane tune that not only is safe, but will provide you more power too.
This is just our opinion, but Lexus is requiring "premium fuel" for their "premium GX550" which actually does not need it. What is more interesting are the rumors that the GX550 uses a slightly smaller turbocharger than the Tundra, and lexus makes nearly identical power figures as the tundra, but requires premium, and uses less boost at higher RPM. This is very interesting. The lexus version does use lower ignition efficiency targets which would allow but not guarantee more ignition could be given (where power can be increased or decreased pretty easily).
Our opinion of the strategy: use premium fuel, Generate similar to, or slightly higher boost psi than the tundra at very low RPM, and dramatically reduce boost pressure in the higher RPMs while using an ignition strategy that calculates as "less efficient" allowing for more ignition timing at higher RPM.
The Tundra just does this easier and doesn't require premium fuel.
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Interesting.
All of your technical expertise and experience aside, there is also the possibility that Lexus calls for “premium” fuel for the GX550 simply because they have a reputation to uphold as a premium vehicle. How could a well-off gentlemen or lady pull up to a gas pump in a vehicle of this caliber and use regular old peasant fuel?
I think we’d all be very interested in a tune that provides more overall HP & torque while burning regular fuel, provided it is 100% completely safe for the vehicle. I think the latter is our highest priority, as opposed to saving a few bucks on gas.
All of your technical expertise and experience aside, there is also the possibility that Lexus calls for “premium” fuel for the GX550 simply because they have a reputation to uphold as a premium vehicle. How could a well-off gentlemen or lady pull up to a gas pump in a vehicle of this caliber and use regular old peasant fuel?
I think we’d all be very interested in a tune that provides more overall HP & torque while burning regular fuel, provided it is 100% completely safe for the vehicle. I think the latter is our highest priority, as opposed to saving a few bucks on gas.
- Thread starter
- #64
It's hard to say for sure, other than the calibration doesn't really reflect the "need" to use premium.
For example the lexus LS500 has this same exact engine and puts down nearly 70 more horsepower, and actually needs premium.
The GX550 is just a watered down Tundra tune with a very small increase in boost pressure at low rpm.
It would make sense that the GX550 requires premium fuel in order to keep up with the brand image.
However....Toyota doing the same thing too.
The Land Cruiser 2.4L Hybrid requires premium fuel.
The 4Runner 2.4L Hybrid requires 87 octane fuel.
The Tacoma 2.4L Hybrid requires 87 octane fuel.
The differences in tunes are...minimal.
It seems to align with the idea that "premium fuel = "higher class of a car"
Hello,
Does this tune work with a GX that has been modified with the Afe intakes and turbo inlet pipes?
Does this tune work with a GX that has been modified with the Afe intakes and turbo inlet pipes?
I see, thank you for the reply!
- Thread starter
- #68
All pending kits have shipped! Thank you everyone.
GX550 CAN connect install instructions will be on our website under "resources" near the Tundra CAN Connect instructions tomorrow.
We sincerely, sincerely appreciate that you guys were so patient with us getting all these kits out.
Pending tune packs will be distributing tomorrow as well.
Finally, VF Tuner will have shipping closed from the 24th - 28th. (will not affect anyone who has already ordered as your kit is already with UPS).
Thank you everyone!
GX550 CAN connect install instructions will be on our website under "resources" near the Tundra CAN Connect instructions tomorrow.
We sincerely, sincerely appreciate that you guys were so patient with us getting all these kits out.
Pending tune packs will be distributing tomorrow as well.
Finally, VF Tuner will have shipping closed from the 24th - 28th. (will not affect anyone who has already ordered as your kit is already with UPS).
Thank you everyone!
How is everyone going regarding doing their tune? I'm surprised no one has posted their reviews yet
Haven't received mine yet.
Just checked tracking....mine is working on taking that right turn in Albuquerque according to the tracking info.
I just reached out to a local tuner about booking some dyno runs...
Are you able to paste the link to the actual tune from the site?
Also, can you please provide a summary of all the features?
I am interested to understand what else other than power output we'll be able to achieve for my Premium plus.
Thanks in advance.
Has the guide been uploaded?
The unplugged cable doesn't connect to the CAN connect cable. Can you confirm this is the correct male that's to be plugged to the CAN connect?
Attachments
I flashed the 91 octane with v2 TCU today. After flashing completed, dash appeared check engine light from TCU lost communication with ECM error. Used my obdii reader and cleared the codes and everything is good. Could also use VF tuner to clear the code but I was not yet familiar with using the diagnostic tools. Initial impression is very nice power pickup from 2k rpm and it keeps pulling to red line. Felt like the car needed much less throttle input to maintain speed/cruise. Transmission is now much more eager to downshift and normal acceleration keeps the powerband in the 3k rpm range. Will likely flash in the 87 tune soon.
This is very helpful! How did you disconnect the CAN connector from the white clip that holds it to the metal? I lifted the tab and the entire end of the connectore fell off, but the CAN is stil connected to the white clip. I also wish this was included in the instructions.
The vehicle’s CAN connector has a black cap that is secured to the frame using the white plastic clip. Since there is limited room to work with, I left everything intact to allow the white clip to hold the CAN connector firm in place. I then bent up the small tab that holds the connector to the cap using a long flat head screwdriver. Once the tab is bent, you can then pry out the white clip and pull on the black cap (with the white clip) to disconnect it from the harness side connector. Attaching the VF’s CAN cable to the vehicle’s connector also requires some finessing. I secured the Wiflash to the area with a zip tie and ran the usb cable down to footwell where it is tucked away.
Have just emailed VF. Mine came with a faulty CAN connect cable. Wifi unit lights up directly when connected to the OBD.... but didn't light up via the can connect cable. The one that came with mine had duct tape and a very average welding job. One of the wires that were welded had snapped ):
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GX550 Forum Photos
GX550 Forum Photos
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