[KanmuriDavid]

As was documented by Motive Garage earlier this year, the first limiting factor on the G16E-GTS is the head gasket. Their head gasket failed at 37 PSI of boost with 485.9 Australian HP at the hubs.

Source:

At the time of Motive Garage's discovery, there were no direct aftermarket replacements for the head studs or gasket. Yesterday, Lamspeed Racing, also located in Australia, announced testing of their own G16E-GTS head stud design. Furthermore, they revealed that they are developing a new head gasket as well.

Spoiler: Lamspeed Racing Facebook Post

Source:

Lamspeed Racing Head Stud Post

The aforementioned head studs have been listed on their website at the link below:

Lamspeed Racing H11 Pro Series Headstuds - Toyota G16E-GTS GR Yaris / Corolla

Details: For applications where you have turned the boost right up over 30psi and plan to keep the head from lifting. This is the first thing that occurs from our testing when pushing the limits from when we set the World Record in our GR Yaris running a 10.5 @ 131mph to then setting the GR...

lamspeedracing.com

This is exciting news as we can expect to see tuners push the limits of this engine further. We are benefitting from the GR Yaris being released a few years ahead of the GR Corolla. I expect Motive Garage and others will try to find what the next limiting factor is on this engine.

 

[Tokyotexan]

Yea, I saw that. I'm sure ARP will be offering a set of head studs in the near future. Seems like the OEM head gasket will be difficult for the aftermarket to replicate, so that may be an issue if the OEM head gasket is not reliable at exponential increases in boost.

The bottom end, particularly the cylinder walls, are extremely beefy for an open deck design.
Does anyone know if the stock rods and pistons on the G16 in the GRY are forged at all?

 

[Tokyotexan]

As was documented by Motive Garage earlier this year, the first limiting factor on the G16E-GTS is the head gasket. Their head gasket failed at 37 PSI of boost with 485.9 Australian HP at the hubs.

Source:

At the time of Motive Garage's discovery, there were no direct aftermarket replacements for the head studs or gasket. Yesterday, Lamspeed Racing, also located in Australia, announced testing of their own G16E-GTS head stud design. Furthermore, they revealed that they are developing a new head gasket as well.

Spoiler: Lamspeed Racing Facebook Post

View attachment 2618

Source:

Lamspeed Racing Head Stud Post

The aforementioned head studs have been listed on their website at the link below:

Lamspeed Racing H11 Pro Series Headstuds - Toyota G16E-GTS GR Yaris / Corolla

Details: For applications where you have turned the boost right up over 30psi and plan to keep the head from lifting. This is the first thing that occurs from our testing when pushing the limits from when we set the World Record in our GR Yaris running a 10.5 @ 131mph to then setting the GR...

lamspeedracing.com

This is exciting news as we can expect to see tuners push the limits of this engine further. We are benefitting from the GR Yaris being released a few years ahead of the GR Corolla. I expect Motive Garage and others will try to find what the next limiting factor is on this engine.

I think motive garage ended up giving away their project GRY to a lucky subscriber, so I don't know how much more they plan on doing regarding the G16.

 

[KanmuriDavid]

Yea, I saw that. I'm sure ARP will be offering a set of head studs in the near future. Seems like the OEM head gasket will be difficult for the aftermarket to replicate, so that may be an issue if the OEM head gasket is not reliable at exponential increases in boost.

The bottom end, particularly the cylinder walls, are extremely beefy for an open deck design.
Does anyone know if the stock rods and pistons on the G16 in the GRY are forged at all?

From the digging I did, it seems the connecting rods are forged, but the pistons are cast.

Source 1: Toyota engines - G16E-GTS
Source 2: YARIS GR ENGINE in depth - G16E-GTS detailed overview and specs - WORLD'S MOST POWERFUL INLINE 3

This changes for the GR Corolla, which has forged pistons, according to The Drive.

Source: Here’s Why the 2023 Toyota GR Corolla Has Three Exhaust Pipes

That being said, I'm sure there are more efficient ways to make power without increasing cylinder pressure, which would ease strain on the head gasket.

 

[Tokyotexan]

From the digging I did, it seems the connecting rods are forged, but the pistons are cast.

Source 1: Toyota engines - G16E-GTS
Source 2: A Dive Inside Toyota GR Corolla’s Potent Three-Banger Engine

That being said, I'm sure there are more efficient ways to make power without increasing cylinder pressure, which would ease strain on the head gasket.

I'm not so sure, GR designed that engine very thoroughly. A set of cams would most likely help, and apparently an upgraded valvetrain is a necessity. Porting the head would probably get you very minimal gains, and probably not worth it. I don't see much potential to make substantial power outside of increasing boost (whether it's the stock turbo or upgraded), upgrading fuel system, and tuning. Upgrading the FMIC and increasing piping diameter seem to help a bit, but honestly the vast majority of GRC owners will be satisfied with 400-450whp.

 

[KanmuriDavid]

I'm not so sure, GR designed that engine very thoroughly. A set of cams would most likely help, and apparently an upgraded valvetrain is a necessity. Porting the head would probably get you very minimal gains, and probably not worth it. I don't see much potential to make substantial power outside of increasing boost (whether it's the stock turbo or upgraded), upgrading fuel system, and tuning. Upgrading the FMIC and increasing piping diameter seem to help a bit, but honestly the vast majority of GRC owners will be satisfied with 400-450whp.

I for sure would be! My goal is just to be in the 400s on stock internals with a safe, driveable tune.

 

[Tokyotexan]

I for sure would be! My goal is just to be in the 400s on stock internals with a safe, driveable tune.

I think the largest obstacle, relating to price is going to be the tunability of the car. The GRY ecu was just cracked after almost 2 years, but I'm guessing the GRC Ecu will be significantly different, therefore it will be back to the drawing board for tuning companies. And the PnP standalone systems are extremely expensive for the GRY.

 

[KanmuriDavid]

I think the largest obstacle, relating to price is going to be the tunability of the car. The GRY ecu was just cracked after almost 2 years, but I'm guessing the GRC Ecu will be significantly different, therefore it will be back to the drawing board for tuning companies. And the PnP standalone systems are extremely expensive for the GRY.

I suspect it'll only be a matter of time. It was a recurring issue with the F model Lexuses as well. Eventually, they all were cracked though. Alternatively, I'm sure standalone options won't take long.

 

[Tokyotexan]

I suspect it'll only be a matter of time. It was a recurring issue with the F model Lexuses as well. Eventually, they all were cracked though. Alternatively, I'm sure standalone options won't take long.

I sure hope so. Doesn't seem to be the case with the supra ECU. I know it's more of a BMW thing, but the 2021+ ECU has yet to be cracked and doesn't seem like it will be anytime soon. The 2023 manual supra guys are gonna hate life...

 

[KanmuriDavid]

I sure hope so. Doesn't seem to be the case with the supra ECU. I know it's more of a BMW thing, but the 2021+ ECU has yet to be cracked and doesn't seem like it will be anytime soon. The 2023 manual supra guys are gonna hate life...

Wife will probably say keep it stock until the warranty is up. Although I might do what I usually do and have wheels just show up at the door and say, "Huh, I wonder where that came from."

 

[Tokyotexan]

Wife will probably say keep it stock until the warranty is up. Although I might do what I usually do and have wheels just show up at the door and say, "Huh, I wonder where that came from."

What wifey don't know won't hurt her...

 

[Tokyotexan]

Wife will probably say keep it stock until the warranty is up. Although I might do what I usually do and have wheels just show up at the door and say, "Huh, I wonder where that came from."

For sure though, wheels and suspension will be first mods, followed by FBO and hopefully a tune. I'll be good with that until warranty is up.

 

[landyman71]

From the digging I did, it seems the connecting rods are forged, but the pistons are cast.

That Autoevolution article is definitely an interesting read! Thanks for the research

“Unfortunately, the GR Corolla doesn’t come with forged internals. Instead, the manufacturer opted for eutectic cast pistons, a popular option with performance tuners.
The G16E-GTS still shares the same D-4S and port fuel injection and 10.5:1 compression ratio as the GR Yaris. Rather than have the turbo and manifold separate, it is integrated into the manifold, with combustion gases passing freely through a triple-exit exhaust system.”

 

[Jeonsa]

That Autoevolution article is definitely an interesting read! Thanks for the research

“Unfortunately, the GR Corolla doesn’t come with forged internals. Instead, the manufacturer opted for eutectic cast pistons, a popular option with performance tuners.
The G16E-GTS still shares the same D-4S and port fuel injection and 10.5:1 compression ratio as the GR Yaris. Rather than have the turbo and manifold separate, it is integrated into the manifold, with combustion gases passing freely through a triple-exit exhaust system.”

Yup I was just about to share this

 

[jdm-v35]

I think the largest obstacle, relating to price is going to be the tunability of the car. The GRY ecu was just cracked after almost 2 years, but I'm guessing the GRC Ecu will be significantly different, therefore it will be back to the drawing board for tuning companies. And the PnP standalone systems are extremely expensive for the GRY.

Just saw the pricing for Syvecs after you mentioned this and yea it is way expensive. Like $6k USD. I am more used to pricing of standalones in the 1500-3000 range like AEM, Haltech or Link. I am hoping those companies get their hands on it and and come out with a solution. I do think the american companies do a much better job at tuning platforms anyway. And Japanese market usually has the best quality aftermarket hard parts. The British seem to not be very good when it comes to aftermarket modification of cars so I also think that is a current market limitation in both parts and tuning. It is primarily in their market and they suck at it.

 

[Tokyotexan]

Just saw the pricing for Syvecs after you mentioned this and yea it is way expensive. Like $6k USD. I am more used to pricing of standalones in the 1500-3000 range like AEM, Haltech or Link. I am hoping those companies get their hands on it and and come out with a solution. I do think the american companies do a much better job at tuning platforms anyway. And Japanese market usually has the best quality aftermarket hard parts. The British seem to not be very good when it comes to aftermarket modification of cars so I also think that is a current market limitation in both parts and tuning. It is primarily in their market and they suck at it.

Yea, Syvecs and Motec are the only PnP ECU's out there for the GRY. Both are over $5k USD as well. Seeing as how Link and Haltech are both Australian I believe, I'm surprised neither of them have come out with a more "affordable" solution. My guess is to how rare the GRY is when compared to other platforms that they build ECU related products for. Perhaps this will change with the release of the GRC. Here is to crossing my fingers and hoping for the best!

 

[jdm-v35]

Yea, Syvecs and Motec are the only PnP ECU's out there for the GRY. Both are over $5k USD as well. Seeing as how Link and Haltech are both Australian I believe, I'm surprised neither of them have come out with a more "affordable" solution. My guess is to how rare the GRY is when compared to other platforms that they build ECU related products for. Perhaps this will change with the release of the GRC. Here is to crossing my fingers and hoping for the best!

It seems like the GRY is not only limitied as a whole but within that it is predominantly more available in the UK market more so than AUS which doesn't make it profitable for them. It took a long time for Haltech to even develop for the 350z platform which was readily available from the get go.

It seems like the GRC will be limited there as well at least for a couple years. I am hoping that companies like AEM or maybe even Cobb will work on it as well.

I do not like the JDM tuning options as they seem to love locking it down to authorized tuners only. ie You needed a key to program an HKS F-con.

 

[Tokyotexan]

I highly doubt COBB will touch anymore ECU related parts. The EPA made them shit their pants, and they abandoned all support for the AP. I don't think AEM has built anything new since the disaster known as the AEM infinity.

 

[jdm-v35]

I highly doubt COBB will touch anymore ECU related parts. The EPA made them shit their pants, and they abandoned all support for the AP. I don't think AEM has built anything new since the disaster known as the AEM infinity.

Then all hope may be lost LOL. Unless there are other platforms that may do toyota tuning?

 

[Tokyotexan]

Then all hope may be lost LOL. Unless there are other platforms that may do toyota tuning?

I do think Haltech, link, and other EMS/ECU companies will eventually roll out tuning solutions. There will be a plethora of piggyback systems out there as well. Hopefully the stock ECU will be cracked and we won't have to worry much. Honestly, only time you will need an all out standalone, is on extensive built engines running huge turbos, large injectors, etc. This will account for approx 10% of the GRC/GRY owners in my opinion. Modern OEM ECU'S are very capable of handling just about anything you throw at them, so long as they are cracked and you have a competent tuner.