What is the cheapest route to replacing the DP and Cat-Back?
Have a custom performance exhaust shop fabricate a complete 3" exhaust system (Turbo-to-Tip). It should cost well less that $400. And then you can use the muffler and exhaust tip of your choice.

Which Fuel Cut Eliminator is recommended?
The GReddy BCC (Boost Cut Controller) is highly recommended.

What does the Fuel Cut Eliminator do?
The factory ECU is programmed to activate a fuel cut if the manifold pressure exceeds 14-15psi. It does this as a safety measure to prevent what the ECU sees as over boosting. The Fuel Cut Eliminator effectively eliminates, or at least raises the cut to a higher pressure. A reprogrammed ECU can also eliminate this function.

Which boost gauge is recommended?
Any high quality boost gauge will work well. Accuracy is the important feature to look for. Autometer gauges are a good value. The Japanese gauges, A’PEXi, GReddy, HKS, etc., have more features, but at a much higher price.

Where can the boost gauge be installed in the interior?
If you want to mount it in the dash, the two most popular places are the Clock location (which holds a 52mm gauge), and the Air Vent beside it (which holds a 60mm gauge). You can also use an A-Pillar gauge pod.

What is the stock boost pressure?
11-12psi

Are Cam Gears a good modification for the Supra TT?
Yes, they have been shown to provide a 5-15rwhp gain on a BPU™'d car. But to extract their potential, you must have them tuned, by a knowledgeable tuner, on a dyno. And most of the power gains will be seen on the exhaust side. I also recommend buying cam gears which feature 5-bolts.

Are Under Drive Pulley(s) a good modification for the Supra TT?
Most of the crank-shaft under-drive pulleys require the removal of the factory torsional damper.

This is from MKIV.com :"this is NOT an external (harmonic) balancer, as the crankshaft is fully balanced, rather it dampens both the axial twisting couples produced by the firing pulses, and the radial bending moment from the accessory drive belt."

Basically this device provides crutial isolation between the engine driven accessories, and the crankshaft. However, removal of this can provide a 10-15rwhp gain, but at a cost for long term use.

Do I need to upgrade the ignition when upgrading to BPU™?
The stock ignition system is VERY capable of supplying enough fire for a BPU™'d car. The stock ignition system uses 6 large coils, one for each cylinder. So the system is capable of supporting VERY impressive HP levels. You may need to change to a colder range plug with a tighter gap (see below).

What about the spark plugs, which are recommended at BPU™ or higher level?
Basically you want similar plugs as stock, but a cooler heat range and a smaller gap. The stock plugs are NGK BKR6EP-11 (2978) and are platinum tipped and have a .044 (1.1mm) gap. The ideal NGK replacement for a modified Supra would be the BKR7E (6097). It is one range cooler (the '7'), is non-platinum tipped (the lack of the 'p') and has a smaller .0315 gap (lack of the '-11'). This plug is also called the NGK 6097 and they are fairly inexpensive. Platinum tipped plugs are not desired for high power applications, Iridium plugs are more prefered. Unfortunately their doesn't seem to be a BKR8E which might be better for high-HP Supras.

Another good plug to try is the Denso Iridium IK22 or IK24. These plugs may last longer than the above mentioned NGKs, but are also 6 times as expensive. The stock replacement plug would be the IK20, the IK22 is one step cooler, and the IK24 is two steps cooler than stock. The IK22 would be good for ~400rwhp to ~600rwhp. The IK24 would probably be a good choice above that. Two other plugs commonly used are the NGK 3330 (BCPR7ES) which differ much more from the specifications of the stock plugs than NGK 6097. Also the Rapid Fire #5 used to be very popular, but are more expensive, don't last as long, and have fallin out of favor. Both of those plugs have been known to cause slight stumbling at idle. Plugs on Supras do not live long, usually around 5,000-10,000 miles. So I recommend replacing them with every other oil change.

What is the HKS VPC and GCC?
It is an electronic device, which electronically and physically removes the highly restrictive mass airflow sensor from the intake tract. VPC stands for Vein Pressure Converter. The HKS GCC is a device that allows further fine-tuning of the VPC.

Do I need an after-market Blow off Valve?
It is not absolutely required, but it is a good idea. The factory by-pass valve is prone to failure, and an aftermarket BOV is probably a wise investment for preventing turbo damaging compressor surge. And it sounds cool too. However, it must be noted that if you still have the factory mass-air flow sensor, a blow-off valve, which is vented to the atmosphere, may cause stumbling between shifts.

Can I run Nitrous Oxide on the Supra TT, even if I am already at BPU™ power levels?
Yes. Most people run 50-75 shot wet manifold systems. If you want to run a higher shot than this, you might want to consider a well-designed direct port system. I have seen as much as a 200-shot used on one of these systems, and an upgraded fuel system would be a must.

450hp just isn't enough, what can I do?
Ah the possibilities Basically you are only limited by your imagination, and your wallet. You know what they say, speed costs money, how fast do you want to go?
The real power lies in Single and Twin turbo upgrades, and the options are limitless. You can either build a mild motor that puts out 450 RWHP all day long with instant boost response, or a 1000+ RWHP monster.

Unfortunately, things start getting more difficult after simple BPU™ modifications. Modification becomes more than "bolt on Downpipe, gain 50hp". Things like tuning, parts selection, and matching combinations of parts become much more important. However, this is the case with ANY high HP car. Actually, even at exceptionally high power levels, the Supra TT is still easier to extract power from than almost any other performance car. But it should be kept in mind, that it wouldn’t be as simple as the BPU™ bolt-ons.

If you just want something that will toast that pesky Viper GTS. Then focus on a mild single turbo upgrade (T04S04, T60-1, SP57-SP61). Along with this, you should install a front mount intercooler, a fuel controller, fuel pulsation damper bypass and EGT gauge. This is assuming you have done all the BPU™ mods, plus BOV, EBC, Cam Gears. With tuning, and a few odds and ends, you should be able to pull 450-500 RWHP (490-580 crank HP) numbers while on a stock fuel system (assuming it is in great condition). This would be a total investment of approximately $6,700-$11,500 in engine/electronic components (also includes the proper gauges). If you already have the BPU™ mods or FMIC, etc., you will spend less than this. The difference in prices reflects the cost of higher end parts and addition of a HKS VPC to replace the restrictive stock MAF.

The next level would require a completely upgraded fuel system, and performance cams would be recommended, as well as further electronics (programmable engine management such as the AEM, or VPC/GCC/ECU combo, etc.). This would allow you to run much larger turbos and injectors. You can make it past the 700RWHP range without needing to replace the internals of the motor with stronger components, even at these power levels, if properly tuned and maintained you should retain a fair amount of reliability while still on the stock internals, as some people have eclipsed the 800RWHP level while still running stock bottom ends in their Supras. If you choose to go ahead and build up the bottom end, then the skies are the limit as far as power goes. Just make sure to have part selection, installation, and tuning done by competent and experienced persons. Although this should hold true at ANY level of modification.

Should I install a Turbo Timer?
Absolutely. Unless you don't mind sitting in your car while it idles down every single time you need to turn the car off. A Turbo timer keeps the engine running for a preset time once you turn off the ignition. So you can remove your keys, and lock up the car and not have to worry about it, it will shut off on it's own. This is important for the life of the turbos. If the turbos are not given time to cool down, it can overheat the oil and cause coking which will block oil flow to the turbos and damage bearings and cook seals.

How much is the Supra's power output affected by changes in ambient temperatures?
Very noticeably, just as with most turbo cars, the Supra Twin Turbo can be very temperature sensitive. Especially with the stock turbos and intercooler. On a BPU™ car, I would not be surprised to see a 10 percent reduction between 50-60deg temperatures, and 90deg plus temperatures

Will the stock clutch hold the power levels of a BPU™ car?
It depends on the condition and wear on the stock clutch. If it is in good condition, yes, it will hold the power, pretty well in fact, although you may experience clutch slip while at full boost in high gears such as 5th and 6th. If you drive vigorously, meaning you run at high boost frequently, then the life of the stocker will be GREATLY shortened. Be surprised if you see an extra 10,000 miles after BPU™.

Can I resurface my flywheel when replacing the clutch?
It is not recommended. Buy a new Toyota Flywheel.

Can I install a lightweight flywheel?
Yes, but be aware that they can create a lot of noise at idle, and can transmit more vibrations and shock to the expensive Getrag transmission.

Why is pulling the TRAC fuse beneficial over just turning it off with the switch on the center console?
Just pushing the "Trac Off" button only partially disables the Trac system. It disables the Trac throttle body and TRAC funtion through the ABS System (on 93.5-96 only), but not the Trac system's ignition timing retard function. Unplugging the Trac fuse eliminates both functions, as well as the 155mph speed limiter, which works through the trac system. The fuse can be found in the main fuse box on the driver’s side of the engine compartment. It must be noted that removing the fuse will cause the TRAC light to stay on, but you'll get used to it.

Will the TRAC system improve the cars performance?
NO. The Trac system was calibrated to improve traction in slippery conditions. It was not calibrated with performance in mind. When the Trac system senses a loss of traction, it comes on hard, cutting power drastically; this will do nothing but hurt performance. I also would not rely on the Trac system for providing stability at high speeds, if you were to loose control, it would be too slow and clumsy, and would more than likely hamper your efforts to regain control. 

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