First thing is first, the stock BEAMS is an incredible engine. It gets pretty decent fuel economy (I was getting 35mpg cruising at 80+mph with a 3.73 final drive), and easily makes 180hp and 140ftlbs at the wheels. That said, most people who use a BEAMS in an AE86 or other chassis end up wanting more power at some point, myself included. IF YOU WANT GOBS OF POWER, EITHER BE PREPARED TO SPEND LOTS OF MONEY OR GO WITH A DIFFERENT POWERTRAIN. The dyno graphs below will give you an idea, especially the one from Panic Wire comparing the different outputs of several engines. The S2000 referenced is a 2.0L.
The problem with the BEAMS is the level of support. With the cost of the BEAMS/trans combos coming down from a few years ago, they are becoming more popular, which means that the support is growing. However, it is still very limited when compared to other more popular power plants.
With that understood, I’m going to break this into two parts. 1st, what can you do with the stock ECU, and 2nd, what to do about better engine management. Since I don’t deal with altezzas a whole lot, this is going to be geared towards my experience with BEAMS swaps in AE86s. However, here is a quick list of common modifications:
Mechanical Throttle Override/Conversion Kit
Intake
Exhaust Manifold
Tunable ECU
Individual Throttle Bodies
Forced Induction
- Supercharger
- Turbocharger
Oiling
- Upgraded Oil Pan
- Dry Sump
Stock ECU Performance Modifications
ETCS Throttle Body Mechanical Override
The Blacktop BEAMS 3SGE utilizes an ETCS throttle body, which functions pretty much the same as the 2JZ ETCS throttle body, if you’re familiar with those. It is a drive by wire throttle body, that has a mechanical override built into one of the sensors. To understand properly how this works, there are a few things that you need to understand about how a drive by wire throttle body works.
The ECU uses multiple inputs to determine the correct throttle position. This consists of things like engine load (derived from mass air flow sensor, coolant temperature sensor, engine RPM, VVTi, etc) as well as driver demand (accelerator pedal position sensor), and is monitored using a throttle postiion sensor.
On most vehicles equipped with a drive by wire throttle body, the accelerator pedal position (APP) sensor is built into the accelerator pedal. This is usually a potentiometer that measures the position of the accelerator/gas pedal, and when you look at the position in the ECU, it is usually a percentage value between 0% (off throttle) and 100% (WOT, pedal to floor).
With the ETCS throttle body, Toyota chose to put the APP sensor on the throttle body itself. while the sensor is a potentiometer, the arm that rotates as you push the pedal has an extra arm/lever on it, that will contact another arm/lever mounted to the throttle plate axle. However, it will only contact it if the throttle motor has not moved the throttle plate, and it will only open the throttle plate about 25%. To me, it looks like Toyota was worried about the drive by wire technology leaving drivers stranded, and wanted to incorporate a fail safe.
Alright, now we can get to the modification. Drive by wire throttle bodies are notorious for “lagging”. It’s not that the motor can’t actuate it fast enough, it’s because vehicle manufacturer’s know that most of their customers don’t want an overly sensitive gas pedal. Since Toyota designed the ETCS throttle body with the previously mentioned fail safe, it is really easy to make the APP sensor contact the throttle plate arm all the time with a spacer/conversion piece. Now, there are two different kinds.
The first is a full kit made by Premium Japan (no affiliation), and appears to be the only one with this design. The Premium Japan kit works that when you push the pedal, it moves the throttle plate first, while the throttle motor “lags” behind and moves the TPS. This gives you that nice, crisp, throttle response. The genius of this kit is that it also retains the capability of controlling cruise control and idle with the ECU. Whereas the second option makes the throttle 100% mechanical.
The second option consists of only the spacer for the APP sensor so it makes contact the entire time. When you install this mechanical override/conversion, you need to disconnect the APP sensor, disconnect the throttle body motor, and remove the middle gear that connects the throttle motor to the throttle plate axle. If you don’t remove/unplug these things, the stock ECU will freak out, and will cut out/stall (ask me how I know…). Interestingly enough, the stock ECU won’t always set codes for the unplugged APP sensor and throttle motor.
This second option is what I recommend if you are using an aftermarket ECU, because there are a bunch that don’t have the throttle body driver module developed/incorporated.
Intakes
There really isn’t much in the way of intakes. You can buy the Blitz, HKS, A’pexi, etc kits, but the problem is that often times they place the MAF in a funny place that the MAF gets biased, which causes some drivability and idle issues. You can purchase a MAF adapter with air flow straightener that works fairly well with the stock ECU. This is what I ran for a couple of years with great success, before switching to a standalone ECU with speed density tuning.
Exhausts
There are several exhaust manifolds available for the Altezza, however, in most LHD vehicles they do not fit. So if you have a BEAMS in a LHD car, your options are pretty much only custom. There are a couple of companies that make the head flange, and then you can have your favorite fabricator weld you something up.
For the cat back, the typical diameter is 2.5″.
Engine Management
The stock ECU is incredibly smart, however, the common failures that I’ve seen with them is inability to interpret 02 sensor readings properly as well as the driver for the throttle body fails. It also isn’t tunable, so if you want to do some crazier modifications, you need an aftermarket ECU. Some considerations when you are looking at options: make sure the ECU is capable of controlling VVTi (it is different than VVT) and extra inputs and outputs are nice to have, in case you do things like add forced induction, flex fuel, etc. Ultimately, the ECU you choose is going to be the one that your tuner is comfortable with. I am of the firm belief that a capable tuner can tune anything. Most sub $2000 standalone ECUs have free or cheap software, and have all of their potential “features” unlocked.
I use an Adaptronic M2000 on my drift car, and I’m very happy with it. Unfortunately Adaptronic is no longer around – they were purchased by Haltech a number of years back and their products have since disappeared. A popular choice is a Panic Made Wiring Harness and Link ECU combo. I think the Link ECUs have the best support for the BEAMS, however, you’ll want to talk to your tuner of choice to determine what ECU they are capable of working with. I would make sure to explain to them that you want functional Dual VVTI – this is the part that many ECUs aren’t capable of controlling due to a limited number of inputs/outputs or hardware/software limitations for Dual VVTI.
Individual Throttle Bodies
For whatever reason, AE86s dudes (and most people), think that everything needs ITBs. They aren’t wrong… they sound glorious. However, what you need to understand is that as of 2019, I haven’t seen ITBs that actually give the BEAMS any peak power over the stock manifold. There are a few that have made claims, however, with these people also make and sell ITB kits for the engine. They also didn’t see a horsepower gain with just a tune on the stock manifold, which is an anomaly in the data that I have gathered. It seems that you can pick up about 20whp over the factory ECU. Honestly, the stock intake manifold is pretty neat – if you take a look in the throttle body hole with a flashlight, you will see tuned velocity stacks in there.
There is one performance advantage to ITBs. They may not give you any additional peak power, however, they do allow you to tune where you make power and for how long. Essentially they can widen your powerband, and different velocity stack lengths can shift it around a bit in the RPM range. So, if you feel that you really need to give your car ITBs, here is what you need to know.
Most people are using Blacktop 4AGE 20V ITBs. These are the largest of the Toyota ITBs, and most AE86 dudes who are putting a BEAMS in had a 20V at some point, or they have a buddy that had a 20V, so these throttle bodies are around. Multiple companies make ITB adapters, you just gotta pick which one you want. Some of them bolt directly to the head, some of them bolt to the rubber/composite spacer that the stock manifold bolts to.
Another option are the Panic Made ITBs. These are larger in diameter than the BT 4AG ITBs so in theory they can make more power. I run these on my street car, and they perform really well but because of their size they are a bit touchy on the throttle. This is great for a track car, but can be a bit tricky for street driving.
There are a few other ITBs on the market from Surfab, EFI hardware, etc.
Once you figure out what adapter or ITBs you want to use, then you can look at velocity stack length. Things that affect this: are you going to run a filter, what filter, are you going to run a strut tower brace, and what adapter you have. All of these change the length of velocity stack that you have space for.
Forced Induction
The stock BEAMS engine can handle low boost (sub 10psi) with careful tuning. Of course there are two different options, superchargers and turbochargers. I won’t try and pretend that I am an expert in either of these areas, but I will give the information that I am aware of.
Superchargers
Once upon a time, Blitz made a bolt on supercharger kit that worked with the stock ECU. It came with a piggyback style fuel controller. This Blitz kit essentially uses an SC14 supercharger. It is a roots style with a clutched pulley, similar to an A/C compressor. This is the bigger brother to the SC12 that came on the 4-AGZE. It works, it makes cool noises, and it gets you extra power, but it doesn’t get you a ton of power. You’re pretty much tapping out the supercharger on the stock engine. This is great reliability wise, because you don’t have to worry about damaging your engine. I ran the Blitz supercharger for several years at 250whp and 200wtq, before eventually the supercharger let go. Unfortunately these superchargers aren’t rebuildable, and the company that manufactures them (Ogura) is difficult to get in touch with.
Some people have been installing Vortech and Rotrex superchargers, however, these are custom mounting kits that are usually being added to built engines. Just like with anything, it is possible, but just be prepared for custom work.
Turbochargers
Just like with the superchargers, there is another sweet JDM tuning company, Greddy Trust, that made a bolt-on turbo kit for the Altezza. It comes with the Greddy e-manage blue, which is a piggyback style engine management system. This kit from Greddy was intended to be used with the stock engine and engine management, however, it would benefit from a more capable ECU. The exhaust manifold is a cast “log style” manifold, and while it will do the job, it isn’t going to flow the best/have the best exhaust scavenging.
In the last couple of years, turbocharger support for the BEAMS 3SGE has really grown. As of 2025, I run a Surfab manifold with a Garrett G30-660. Turbo support is still in its introductory phase, but it’s getting better. On a stock unopened engine and 10psi of boost, I made 340whp and 250wtq.
Oiling
Upgraded Oil Pans
One of the drawbacks to swapping in a BEAMS is that it is a tall engine. On cars like AE86s, the oil pan tends to hang below the crossmember, causing some ground clearance problems. There aren’t shortened oil pans made for them right now, but there have been exploration into them.
You have a couple of options with low profile oil pans for BEAMS 3SGE swaps – Surfab and JSP Fab. The Surfab oil pan can be made for engines that are either mounted perfectly flat or tilted at the factory angle, whereas the JSP Fab oil pan requires the factory tilt angle. I run the JSP Fab oil pan on my N/A ITB Street Car, and it gives GREAT ground clearance and looks beautiful. I haven’t had any oil pressure issues with it yet, and JSP did a significant amount of track testing when they made the oil pan.
Dry Sump
To my understanding, a dry sump oiling systems use a small sump with siphon pump(s) to pull oil from the pan and store it in an external container that is less likely to slosh oil away from the “pickup” under high G acceleration or cornering. Another pump is used to pull it from the oil container and send it to the engine. The pumps bolt together and are driven off of the same gear, which is driven by the engine. There are a couple of hurdles with the dry sump setup – a custom pulley setup for the dry sump pump, custom mount for the pump, removing/isolating the factory oil pump from the engine (running the factory oil pump and the dry sump pump can cause the pumps to fight each other and cavitate the oil).