2024 Lexus GX 550 OT+ Build

xonn · Sep 4, 2024

New GX550 OT+ with 1700ish miles on it. So far it's been great and a huge upgrade over the car it replaced.

Not planning to go too crazy with it since I like how it already sits from an exterior standpoint. Mods so far include:

Exterior and Interior:

Xpel PPF Wrap on Front Clip
Full Ceramic
35% Tint of Front Glass
Leather Shield Ceramic for Interior
Fake engine noise coded out (SOOOOOOO much better)

Performance:

JB4 Map 2

Initial Thoughts:

Getting rid of the augmented engine sound was a HUGE upgrade for me as far as interior comfort. For my ears, it drones especially in the Sport+ drive mode. Fortunately, it can be disabled at the dealership without impacting the noise cancelation.

The JB4 running on Map 2 really woke the GX up. Part throttle driving is vastly improved with acceleration feeling even more effortless than stock.

Cajun Heat · Sep 4, 2024

xonn said:
New GX550 OT+ with 1700ish miles on it. So far it's been great and a huge upgrade over the car it replaced.

Not planning to go too crazy with it since I like how it already sits from an exterior standpoint. Mods so far include:

Exterior and Interior:

Xpel PPF Wrap on Front Clip
Full Ceramic
35% Tint of Front Glass
Leather Shield Ceramic for Interior
Fake engine noise coded out (SOOOOOOO much better)

Performance:

JB4 Map 2

Initial Thoughts:

Getting rid of the augmented engine sound was a HUGE upgrade for me as far as interior comfort. For my ears, it drones especially in the Sport+ drive mode. Fortunately, it can be disabled at the dealership without impacting the noise cancelation.

The JB4 running on Map 2 really woke the GX up. Part throttle driving is vastly improved with acceleration feeling even more effortless than stock.
View attachment 3137

Congrats and welcome to the forum.

rkeezy22 · Sep 4, 2024

What are the new HP/Torque figures with the JB4? Do you have a report to share from the tune?

ilumo · Sep 4, 2024

Yea. Very interested in the tune. Didn’t even know they made a tune for this engine.

xonn · Sep 4, 2024

rkeezy22 said:
What are the new HP/Torque figures with the JB4? Do you have a report to share from the tune?

I haven’t dyno’d it but it does feel noticeably more responsive and quicker. Their claim of +75 hp is likely accurate.

xonn · Sep 4, 2024

ilumo said:
Yea. Very interested in the tune. Didn’t even know they made a tune for this engine.

Yep they do. I’ve also been running their system on my Supra in tandem with an ECU tune for the past 4 years without issue.

It really does produce good results as long as you have enough octane. 93 octane is required / highly recommended for Map 2.

rkeezy22 · Sep 4, 2024

xonn said:
I haven’t dyno’d it but it does feel noticeably more responsive and quicker. Their claim of +75 hp is likely accurate.

How do you know it's not too much for the engine if you don't know the outputs/how much boost is running at each RPM at least? Can you pull that without a DYNO?

xonn · Sep 5, 2024

rkeezy22 said:
How do you know it's not too much for the engine if you don't know the outputs/how much boost is running at each RPM at least? Can you pull that without a DYNO?

Because I've reviewed the logs and also had the folks at Burger Tuning review them. On average it's 4 psi over stock depending on load.

JB4 allows you to log a number of parameters to assess how the engine is running.

Mainelexus · Sep 5, 2024

That would be fun, but also probably kill engine warranty. Gotta pay to play.

ilumo · Sep 7, 2024

Speaking of dynos. Does anyone have a stock dyno sheet for these cars? I wonder if the factory specs are underrated, overrated or inline with real world results. .

xonn · Sep 7, 2024

I imagine there's quite a bit of driveline loss with the GX. If a stock GX breaks 300 whp that'd be seriously impressive. I'd imagine it'll put down 280 - 290 whp assuming ~20% driveline loss. I'm sure someone will dyno one eventually. If there's ever an ECU tune available, you'll start seeing them on the dyno.

ilumo · Sep 11, 2024

xonn said:
I imagine there's quite a bit of driveline loss with the GX. If a stock GX breaks 300 whp that'd be seriously impressive. I'd imagine it'll put down 280 - 290 whp assuming ~20% driveline loss. I'm sure someone will dyno one eventually. If there's ever an ECU tune available, you'll start seeing them on the dyno.

I believe there were some piggy back tunes people were using. Jb4 or something like that. There was no dyno info in that thread though.

sixsigma43 · Oct 4, 2024

How do you code out the fake engine noises? What tool is required to do this?

Bluegill · Oct 4, 2024

The dealer turned my fake engine noises off at my 5,000 mile service.

rkeezy22 · Oct 4, 2024

I used this and the free trial

https://a.co/d/2M5qaoX

incognito.gx · Oct 4, 2024

Bluegill said:
The dealer turned my fake engine noises off at my 5,000 mile service.

I need to remember to do this. Kinda wild the dealer has to do it

xonn · Oct 4, 2024

The dealership can do it. Doesn't cost anything if you go with them.

sixsigma43 · Oct 22, 2024

xonn said:
New GX550 OT+ with 1700ish miles on it. So far it's been great and a huge upgrade over the car it replaced.

Not planning to go too crazy with it since I like how it already sits from an exterior standpoint. Mods so far include:

Exterior and Interior:

Xpel PPF Wrap on Front Clip
Full Ceramic
35% Tint of Front Glass
Leather Shield Ceramic for Interior
Fake engine noise coded out (SOOOOOOO much better)

Performance:

JB4 Map 2

Initial Thoughts:

Getting rid of the augmented engine sound was a HUGE upgrade for me as far as interior comfort. For my ears, it drones especially in the Sport+ drive mode. Fortunately, it can be disabled at the dealership without impacting the noise cancelation.

The JB4 running on Map 2 really woke the GX up. Part throttle driving is vastly improved with acceleration feeling even more effortless than stock.
View attachment 3137

Any further feedback on JB4, how is drivability compared to stock, what are pros and cons and how difficult was installation?

xonn · Oct 22, 2024

sixsigma43 said:
Any further feedback on JB4, how is drivability compared to stock, what are pros and cons and how difficult was installation?

It's better in every way over stock. More torque everywhere. I have 93 octane where I live which enables you to run map 2.

GX has right at 5k miles on it which works out to ~3300 with JB4 installed. The JB4 has been flawless. I've used it on my other cars in the past so knew what to expect.

Installation takes all of 20 minutes if you're slow. It's 2 connectors and then routing the OBD2 cable inside the cabin which is simple because of the grommet between the engine bay and cabin.

sixsigma43 · Oct 22, 2024

xonn said:
It's better in every way over stock. More torque everywhere. I have 93 octane where I live which enables you to run map 2.

GX has right at 5k miles on it which works out to ~3300 with JB4 installed. The JB4 has been flawless. I've used it on my other cars in the past so knew what to expect.

Installation takes all of 20 minutes if you're slow. It's 2 connectors and then routing the OBD2 cable inside the cabin which is simple because of the grommet between the engine bay and cabin.

Would you happen to have the correct part number for the JB4 compatible with the car? Also where did you purchase?

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