For anyone looking into intakes — just a heads-up. The intake and MAF housing on the aFe setup is definitely a bottleneck. Compared to a custom pipe that mates directly to the 76 mm Tundra throttle body, the aFe flows on average at least 5% less after 5,000 rpm. Injen and AEM also don’t mate directly to the larger 76 mm TB, so they have the same limitation.

The only way I’ve found to get better flow past 5,500 rpm is to go fully custom. Right now this is the biggest bottleneck in my setup.

 

Have you actually measured the tube end that connects to the TB on the Injen and AEM?

 

I haven’t physically measured the Injen or AEM tube ends myself, but their install docs show they use a 2.75" coupler at the TB side, which works out to about 70 mm ID — basically OEM throttle body size.

Curious — what’s the ID on your intake? Are you running the OEM size or a 76 mm Tundra TB?

 

I have both the AEM and Injen tube. I'll try to measure them when I get a chance to see what they actually measure. I don't have the 76mm TB. I sent my TB to a guy a few years ago and he Bored, ported, polished and funnel venturi shaped it to 74mm. Also be aware that the MAF needs to be able to measure a certian tube size air flow, not too big. The MAF can get too much air to measure correctly. Even if Tuned it has a Max parameter amount it can handle to be tuned.

Do you have a pic of your exhaust from the Headers back? I think you mentioned one time what you were running, but I forgot. What's your current exhaust set up now?

This Guy did some test on the 2.5, 2.75, 3.0 Tubes and MAF.

https://wilhelmraceworks.com/blog/2g...EeKSNS2I_wsnDP


Ever seen this Intake Mani? I have one. They use to sell it as a kit on ebay. Maybe some day.

 

The whole realization for me came when DickH compared his datalogs to mine — we’re running almost the same setup right now, at least until my fully built IPT tranny goes in mid next month. Beyond that I’m in the middle of a bored-out build (I’ll post full specs when I get a chance). The pistons alone are works of art: 4032 JE with side coatings, 3D underside milling, dual oil accumulators, external bracing, the whole deal.

Anyway, Dick’s setup flows on average about 5% more after 5,000 rpm compared to mine. The main difference is that I’m still on the aFe intake, which I know is not ideal. My 69mm ID intake has a pretty comical step-up at the TB coupler, and that’s obviously hurting flow. He may be able to hook me up with the exact same intake soon. I’ll also check out that article you linked. I briefly glanced at it and his testing seems to be before we went to a 76m Tundra TB. Also he mentions Frankenstein Motorworks and their MAF housing, which is 3.5" biggest of them all. Bigger than DickH and much bigger than stock size. You are absolutely right about keeping the MAF housing stock ID as anything else seems to be a calibration and accuracy nightmare and sometimes accuracy is just not possible. DickH's success is what motivated me.

As for exhaust, I’m still running the same setup: ceramic-coated PPE headers → ceramic-coated resonated Apexi mid-pipe, with a ceramic-coated Magnaflow X-pipe welded in right after the transmission pan where the bend correction is (closest I could get it to the collectors, still a little further than ideal) → ceramic-coated Tanabe axle-backs. The one bottleneck is the flange at the mid-pipe/axle-back connection. Both systems were designed to mate to the OEM flange, so they step down there — I’ll be replacing that with proper diameter soon.

That intake you’ve got looks killer, definitely better than the ported OEM lower I’m using. The casting shifts in some OEM lowers are appalling — I’ve got three of them and one is shockingly bad. Dick is working on something next-level right now, and Larry should be able to flow test it with both OEM and ported heads. We should have numbers soon, though it’ll still be a few months before his “master creation” is ready.

Here’s a pic of what Dick put together — 3.5" mandrel tubing, totally custom — and it clearly works.

 

I’ve just added a detailed new entry at the top post covering the fully built IPT A760H transmission, IPT-built AWD transfer case, high-stall torque converter, and Tru-Cool LPD transmission cooler installation.
This upgrade has transformed the drivability of the car — temperatures stay below 190°F, shifts are crisper, throttle response is sharper, and acceleration is noticeably stronger.
The new section includes technical notes on the 1–2 shift behavior, launch characteristics, and initial performance impressions.
If you’ve been curious about IPT’s full build for the GS platform, this update gives a deep look at real-world results.

 

I put the new intake that DickH made with a filter I bought from Injen. You guys think it's a little undersized?

 

I have been driving a little on the DickH custom intake set up and wow. It is unbelievable how much more power it makes. It turns out with the PPE headers, ported intake manifold and large Tundra TB the aFe stage-2, oiled intake was a major bottle neck. It pulls so much harder that it pushes me into the seat now. It smoother, and quieter too. Absolutely shocking, the difference.

Now I will get you the shifting video next.

And in about 14 weeks we will have the full out NA motor in this thing.

 

have you considered making any adjustments to the inlets on the radiator cover? That seem to be the last point of restriction on the intake side. That, and the ram air snorkel. I guess you could open that up as well

 

Are you suggesting cutting some of the tabs off?

 

I am super stoked to say that DickH is making a V2 with a built in air straightener to this already incredible design. I will post more photos when it arrives.

 

Maybe? Idk if I would do it to my one and only piece, but since you're kinda trailblazing this stuff, it might be something worth testing if you find a radiator shroud at a junkyard. Maybe the tabs are restricting flow? I'm sure they're guiding the air up into the right direction but maybe there's a less restrictive way to do it. Maybe a scoop underneath to force the air up?

 

That’s a fair line of thinking, and I appreciate you fleshing it out a bit more.

Right now I’m hesitant to start cutting the OEM radiator shroud on my only good piece, mainly because Lexus did put real aero intent into those tabs — they’re not just random plastic. They’re clearly there to manage pressure differential and guide airflow upward toward the intake zone rather than letting it spill or stagnate.

That said, I do agree this is probably the last remaining untouched choke point on the intake side, at least from an upstream airflow-management perspective rather than outright cross-sectional area. Once the V2 intake with the integrated air straightener is on and I can get more data (logs, trims, real-world behavior), it’ll be easier to tell whether upstream turbulence or pressure recovery is still leaving performance on the table.

Your junkyard shroud idea is actually a good one. If I can source a spare, that opens the door to controlled testing — trimming tabs vs. reshaping vs. possibly adding a subtle under-tray scoop to increase stagnation pressure without wrecking airflow quality (turbulence). I’d much rather experiment that way than guess and permanently modify the only factory part.

For now, I’m letting the intake system “settle” in its current form and seeing how the V2 behaves. If the data suggests the intake is still pressure-starved at speed, revisiting the shroud with a test mule makes a lot of sense.

Good thoughts — this is exactly the kind of detail-level discussion that makes this fun.

 

I added a quick write up of my AEM340 low pressure fuel pump upgrade. I don't know why I waited so long for this one really. Nice upgrade overall.

 

Speaking of data, any acceleration data? dragy is cheap.

Following for the trans changes, I might need IPT to start working on the AA80E