This thread will supplement my main White Pigeon build thread, but here I’ll be focusing strictly on the engine and transmission development. The goal is to create a clear reference for anyone pushing the 2GR-FSE / A760H platform.

Transmission – Import Performance Transmissions Max Effort Build (A760H)

This is my actual transmission:
📹 IPT Build Video – my unit
📹 General A760E Breakdown

The second video is especially worth watching — it shows what happens to a stock A761E when you slap a supercharger on a 2GR-FSE.

IPT Fully Built A760H Transmission + IPT-Built Transfer Case + High-Stall Converter + Tru-Cool LPD Cooler

To complement the power gains from the 2GR-FSE build, I upgraded the driveline with a fully built IPT A760H and a built AWD transfer case, paired with a custom high-stall converter and Tru-Cool LPD transmission cooler.

Highlights:

• Transmission: Full IPT build with upgraded clutches, valve body modifications (overbored), and line-pressure recalibration for faster, firmer shifts.
  
• Converter: High-stall AWD-spec, now flashing to ~2,400 rpm (≈ +400 rpm over stock).
  
• Transfer case: IPT-built for tighter coupling and reliability under increased torque.
  
• Cooling: Tru-Cool LPD external cooler — temps never exceed 190 °F under any conditions.
  

Driving impressions:

• Acceleration is noticeably stronger and throttle response dramatically improved.
  
• The drivetrain feels tighter, with more direct torque transfer.
  
• All shifts are smoother and quicker than stock, except for a firmer 1–2 at light throttle, which gives a small kick typical of higher-pressure builds.
  
• The mild gear-train whine adds to the feedback — it feels mechanical, not intrusive.
  
• Full-throttle upshifts at 7,400 rpm are precise, though the final shift is slightly slower at the very top end.
  

Summary:
The IPT transmission and transfer case have completely transformed how the AWD platform behaves — faster, cooler, tighter, and far more engaging to drive.
John at IPT told me this build should handle 600–700 HP max, but that he feels most comfortable with it living in the 500 HP range. That’s perfect for my goals — reliability and consistency first, with plenty of overhead for future power.

Engine – Larry’s Engine & Marine (Tucson, AZ)

The engine is being built by Larry’s Engine & Marine, recommended by Eden Customs. I sent them a 2GR-FSE from a 2013 GS350 AWD with ~80k miles that was rear-ended.

Teardown findings:

• Everything looked surprisingly clean.
  
• Oil pump housing was heavily scored by the pump gears — seems to be a common 2GR issue.
  
• High pressure fuel pump (HPFP) was also badly scored. Toyota clearly knows about this, since multiple revisions of the HPFP exist.
  

I sourced a fresh OEM 23100-39646 fuel pump for the build. This is the latest revision by Lexus, hopefully it solves the scoring issue. It does address and issue with damage by ethanol content that Lexus saw in older revisions.

New OEM Parts

I got a new OEM oil pump housing since the old one was scored.
The old rocker arms were just fine but I got the revised 13801-38020 OEM rocker arms, new. The old revision, the ones on the car were stamped. These are forged.
I sourced new engine gaskets: 04111-31942 Unfortunately this includes the head gasket too which I have no use for since I am using the Cometic over sized gasket for the bigger bore.
I also sourced new OEM main cap bolts nine of the shorter and 7 of the longer ones totaling 16.
I got new port and direct injectors (brown) that have been remanufactured by GB Remanufacturing.
Fun fact the direct injectors have 4 different specs; brown, yellow, black, green.

Cylinder Heads – Trigga Spec Porting

Fresh OEM heads, expertly hand-ported by Trigga Spec.
CNC porting is repeatable, but a veteran hand porter can achieve superior results. Trigga’s work proves that.

Preliminary flow testing (at 28” H₂O with OEM intake manifold):
Intake:

• .100" → 117 CFM
• .200" → 207 CFM
• .300" → 272 CFM
• .400" → 306 CFM
• .500" → 321 CFM
• .600" → 329 CFM
• .700" → 334 CFM

Exhaust:

• .100" → 70 CFM
• .200" → 124 CFM
• .300" → 159 CFM
• .400" → 178 CFM
• .500" → 186 CFM
• .600" → 192 CFM
• .700" → 197 CFM

Important note: these numbers were with the OEM intake manifold, which creates a serious mismatch. The head ports are significantly larger — I saw this myself when Larry showed me. We’ll redo testing with the ported intake manifold and I’ll post updated numbers.

Valvetrain – Supertech

Full Supertech valvetrain installed:

• Dual valve springs: SPRK-EC3025D-2GR
• Titanium retainers: SPRK-EC3025D-2GR
• Inconel exhaust valves: TEVI-1056D
• Black nitride intake valves: TIVN-1056D
• Valve Stem Seals: VS-SU5.5EI-8
• Valve Locks: KPR-5.5-7A-ST-24

Camshafts – Web Cam (Hard Welded)

The cams are OEM cams hard welded and ground by Web Cam Racing Cams.

Profile #1751 (intake): 0.283" lift (+0.033" vs stock 0.250"), 238° @ 0.050" (+21° vs stock 217°), 262° @ 0.010", ramp 47
I am running 4 of these. So intake and exhaust are the same profile.

Pistons & Wrist Pins – JE Custom

• JE Pistons → forged 4032, 97mm bore, part # 401161.
• Crown → Thermal barrier coating by JE.
• 3D under crown milling → by JE
• Skirt → Tuff coating by JE
• Oil accumulator groves → by JE
• External bracing → by JE
• Wrist pins → by JE, part # H8662250185CD
• Wrist pins coating → DLC by JE.
• Offset pins → by JE
• Rings → by JE, part # JG1006-3819
• Sleeves →Darton MID liners, 97mm bore, part # 900-500.

Connecting Rods

Pauter Custom rods → forged 4340 chrome-moly, part # TOY-220-560-1475F6
Shot-peen → by Pauter

Bearings

Main bearings → King Bearings, coated by them in Molybdenum disulfide (MoS₂)
Rod bearings → ACL Race Series, part # 6B8466H

Coatings – Polydyn, Line2Line

• Windage tray (both sides) → oil shedding compound, Polydyn, I sent a new OEM part for cleanliness.
• Oil pan upper (inside) → oil shedding compound, Polydyn.
• Oil pump gears → Line2line coating.

Head Studs

I wanted to run Automotive Racing Products head studs, I called them to get it from them but they said it woudl be best if I order from Monkey Wrench Racing as ARP makes a special head stud set for the 2GR-FSE engine for them. So I got the MWR-108021 kit from MWR, this is an ARP2000 stud kit.

Oil System Concerns

One of the most concerning discoveries in teardown was the oil pump wear — scored housing at just 80k miles on a gently driven donor motor.

• I sourced a new housing and gears, but I don’t want to see it chewed up again.
• Line2Line coated the oil pump gears.

I also wanted to coat the inside of the valve covers, but Toyota riveted hard oil lines to the underside — very unusual. Technically possible (laser blast + mask), but Carl advised against it.

Crank Scraper

To further strengthen the bottom end and improve oil control, we have added an Ishihara-Johnson PTFE-edged crank scraper. This will work in tandem with the OEM windage tray to strip oil from the rotating assembly at higher RPM, helping reduce windage losses, improve oil return, and keep pressure more stable during sustained high revs.

They offer two options a steel and a Teflon bladed one. We started with steel as Larry feels most comfortable with that and can can machine it perfectly for our needs. Kevin at Ishihara-Johnson edged crank scrapers guaranteed more power with the Teflon one. We ran into some repeated small issues with the Teflon scraper. We switched back to the steel ones.

Head Gasket

We got oversized head gaskets from Cometic for the oversized bore

Fun fact I didn’t know until this build: the 2GR-FSE has piston cooling oil squirters from the factory. Very cool detail.

Current Status

This is where the engine + transmission build currently stands.
In the next post, I’ll lay out what’s coming next (coatings, carbon driveshaft, etc.).

 

White Pigeon Powertrain: Next Steps (Future Engine & Transmission Plans)

With the transmission complete and the heads/valvetrain/cams/coatings squared away, the next phase is pushing the bottom end, coatings, and driveline upgrades. Here’s what’s ahead:

Stroker Kit Considerations

After considering multiple approaches to increase displacement, we decided to drop the stroker idea altogether and instead focus on building the strongest and most balanced bottom end possible.

Merlin Developments confirmed they will not be producing another 2GR stroker kit like they had in the past, and the 1GR crank isn’t a simple drop-in solution for this platform. Offset grinding the OEM crank was also ruled out — the factory surface is nitride-treated, and removing that layer through grinding would compromise durability.

Valvetrain Additions

I know Monkey Wrench Racing has its critics (I’ve personally had one of their parts snap in my hand like a dry twig), but I’m seriously considering their hydraulic lash adjusters with retainers. Larry and I decided that the hydraulic lash adjuster retainers combined with MWR's recent not-so-great part reliability and proper spring force with the Supertech spring kit makes this more trouble than it is worth, we are not doing this.

Driveline & Cooling

• Custom carbon fiber driveshaft → being built by The Driveshaft Shop.
• Engine oil cooler → custom made by notrigga@gmail.com
• FIGS Engineering rear diff bushings → full polyurethane kit replacing the OEM rubber, removing the Super Now collars.
• Rear diff cover → I’ll be coating the inside with PolyDyn oil-shedding compound for added protection and efficiency.

 

See you have gone all out on your GS. I don't know if you have seen this YT before but it may help with some info for you.

I would be careful with the Piston Bore increase and head work. Getting thin in places could create a motor that overheats the cooling system, that would have the water jacket too thin, and a after build overheating engine problem. Also the assembly will be crucial, in getting the correct compression along with a very well deck height and piston squish accuracy.

What are you thinking about for Rods? Keep us updated!

 

No build like this happens in isolation. The White Pigeon project has been possible thanks to the help, guidance, and expertise of many individuals and companies. I want to take a moment to acknowledge them here:

🔧 Engine / Machine Work

• Larry’s Engine & Marine Inc. – Tucson, AZ → Full engine build/assembly, sleeving, flowbenching.
  
• Trigga Spec (notrigga@gmail.com) – Expert hand porting of the 2GR-FSE heads and intake manifolds.
  
• True Bore – Precision machining services, critical to making sure everything fits and seals as it should.
• JE Pistons (Freddy) – Helping design and build the custom 4032 forged piston set for the 2GR-FSE.
• Ishihara-Johnson Crank Scrapers (Kevin) - Making a really nice crank scraper for the 2GR-FSE and all his knowledge

⚙️ Cams / Valvetrain / Knowledge

• Web Camshafts (Faith) – Hardwelded cams and direct technical support.
• Bullet Camshafts (John Partridge) – Custom billet cams
• Frankenstein Motorworks (Marc Labranche) – Excellent insight and resources for pushing Toyota V6 platforms further.
  
• JGScott (Club Lexus) – For his detailed technical posts, knowledge, and willingness to share experience.
  
• DickH (Club Lexus) – For deep platform knowledge, testing, and always being willing to answer questions.
• GB Remanufacturing – Best high pressure injector remanufacturers in the US, and a wealth of knowledge, super helpful.

🛠 Coatings & Components

• PolyDyn Performance Coatings (Carl) – Oil shedding, dry film lubricant, and ceramic work throughout the build.
  
• Industrial Hard Carbon (Mike) – DLC coating work on rollers, ensuring durability and reliability at high loads.
  
• Non-Stop Tuning – Lightweight tensioner and idler pulleys that freed up rotating mass.
  
• RR Racing (Rafi) – For performance parts and engineering solutions tailored to the 2GR-FSE platform.
  

🚗 Transmission / Driveline / Exhaust

• IPT Transmissions (John) – Max-effort A760H build, high-stall converter, upgraded valve body.
  
• Atlas Transmission (Tony) - Tucson, AZ – Local expertise and support on drivetrain service and logistics.
  
• Exhaust Works Tucson - Tucson, AZ – Trusted shop for X-pipe install, cutting/welding, and exhaust work done right.
• The Driveshaft Shop – Building a custom carbon fiber driveshaft for the GS.
• PPE Engineering – Equal-length headers, ceramic-coated for heat management, with excellent customer support.

📏 Support & Community

• Eden Customs (Trung) - Tucson, AZ – The one who first put me in touch with Larry’s, and a strong supporter of the build.
  
• Leksfixit (Mark)– Phoenix, AZ - For Lexus-specific problem-solving knowledge and advice that saved me time and mistakes.
• Top End Motorsports - Great and fast support for some very cool and niche parts
  

🎛 Tune

• Tuned by Loi (Loi Tran, tunedbyloi@gmail.com) – For tuning expertise and making the most out of every hardware change along the way.

Closing

This project wouldn’t be possible without the help of these people and companies. Each of them has contributed in a meaningful way to pushing the 2GR-FSE and A760H platforms further than most would ever attempt.

If you’re planning to build a GS350, IS350, or any 2GR-FSE powered Lexus — these are the names I’d recommend you keep on your radar.

 

Did you decide what type of transmission cooler you will use?

 

Thanks a lot for sharing that video—it’s very instructional and really great. 🙏 I’m going Darton MIDs as well, and right now we’re figuring out the rods. First step is confirming whether the stroker is a go or no-go. That top register sleeve approach is very interesting, I’ll be looking deeper into it.

I’ll definitely insist on a line bore with a torque plate. I also really like the idea of ring packs moved down—OEM pistons have the surface way too close to the first ring. I’m also considering WPC treatment; maybe springs, rods, and even retainers could benefit.

Appreciate the caution on bore increase and head work—I’ll be keeping an eye on water jacket thickness and deck/piston squish accuracy. Thanks again for the heads up and for sharing solid info!

 

Wow.

Does IPT have any notes on transmission tuning their built transmission? I would love to have an A761 that shifts (manually) like a ZF 8HP.

 

Mine can shift manually stock, if you don't have it, it is likely an OEM option that you can add. That's probably your easiest bet.

 

Mine does as well, but 75% of the "rev-matched" downshifts feel like someone learning how to drive stick for the first time.

 

Totally get what you’re describing, but I actually haven’t been having that issue. Manual downshifts do feel slightly slower, but that’s been consistent across my last three cars too, so it doesn’t stand out to me.

FWIW, my guy Loi sorted this with transmission tuning before my IPT swap, so it wasn’t really on my radar after that. If you want to dial yours in, shoot him an email: tunedbyloi@gmail.com — you can tell him Alp sent you.

 

I was not aware that anyone was able to clean up the manual shifting/rev-match tune. Have you spoken to IPT about how their transmission will interact with the Loi tune or the factory tune?

 

Rev-matching itself is handled by the factory ECU/TCU logic, and it can’t really be rewritten from scratch. What Loi can do is refine how the transmission behaves around it. He explained that on the GS350 the transmission tables are somewhat limited, but he’s able to:

• Adjust how firm or soft both upshifts and downshifts feel.
  
• Change the shift points.
  
• Control torque converter behavior, including working with a high-stall unit.
  
• Remove shift torque reduction for a sportier, more connected feel.
  

So, while he can’t create an all-new rev-match system, he can clean up the factory behavior by making the downshifts firmer and quicker, and by managing torque converter response so it feels sharper and more consistent. The IPT transmission upgrades should complement this by physically making the shifts faster and more decisive.

I did check with Loi about how his tune will work once the IPT transmission is installed, and he’s confident it won’t be an issue. Running on his “stock transmission” tune now won’t hurt anything — once the IPT unit is in, we’ll datalog and he can fine-tune the transmission behavior to match the new hardware.

That said, I’m currently running into major problems with IPT — they sent me the wrong torque converter with the built transmission. It’s created a huge delay because the car is already apart and waiting for the correct high-stall converter to be built and shipped back. Once the right parts are in place, though, the combination of IPT’s hardware and Loi’s tuning should really come together.

 

Thank you for this very comprehensive response. I was always curious about what level of tuneability was available through the factory TCU.

That is very unfortunate to hear about IPT. They appear to be the only game in town for built Aisin transmissions.

What pushed you to the higher stall converter? I've only driven high stall cammed LS1s and LS2s with 4L60s, but these were 3500-3800 for drag racing and made both highway cruising and around town driving fairly unpleasant. For the kind of driving I do, I think I would prefer a stock stall speed and for the converter to lock as low as safely possible, but I also prefer to drive manual or DCT cars.

 

Yeah, I totally hear you on high-stall converters — a 3,500–3,800 stall on a 4L60 makes sense for a strip-oriented LS build, but it would be miserable for daily use. I’m going a different route since my engine profile is a lot milder in comparison. The cam I’m leaning toward is this grind:
The “+” numbers are the delta from stock, and with the 1.7 rocker ratio they multiply out to pretty healthy valve lift.

Because of that, I’m only looking at a mild increase in stall — just enough to get me closer into the powerband when I want to get out in a hurry, but still very streetable. Rev limiter is going to be 8,000 rpm, so the higher shift points and cam profile justify a little extra stall without making cruising or stop-and-go unbearable.

The frustrating part is IPT. After they lost my original converter, they promised a 5-day turnaround if I sent them another one. I reminded them it was pretty messed up considering the situation, but since they refused to warranty the fully built transmission if I went with Ultimate Converter Concepts or Precision of Hampton, I sent them another OEM converter anyway. Now they’ve pushed that promise out to “two weeks,” all while my car is literally sitting outside with the transmission out.

If I wasn’t already planning on swapping the engine and going to a carbon-fiber driveshaft, I’d honestly give up on their warranty and just go with UCC today. Their +1,000 rpm stall option is exactly where I want to be compared to IPT’s more conservative +500 rpm approach. Also I have much more confidence in UCCs product now and their ability to deliver on time.

 

Always watching the progress on your 4gs, love the build and where it's going. Been thinking of doing something similar with my 2gr-fks, would it be possible for you to provide a cost for each item or at least a general cost for each area (engine, trans, rotating assembly etc.)?