'Different Stages of Tuning' Guide??

Hi there,

I've had a quick search and could't find anything, but I wondered if anybody had done a guide explaining the different stages of tuning on the Supra?

The most important thing being that says when to certain parts reach their limits and need upgrading (e.g. aftermarket fuel pump need @ 400hp)

Something like this, which was written for an 2nd Gen RX-7;

FC3sPRO: Mild to Wild

Cheers

Click here: BPU

could be a good thread with the rite posts from the rite people

could be a good thread with the rite posts from the rite people

It's been covered though - there's BPU, then you can add various bits to that like intercooler, cams, ECU or fuel controller, boost controller, then it's on to a single turbo conversion (or big twins if you have a huge budget) and then a built engine. You don't have to do it all in that order, but that's the generally accepted route.

I'll throw in my experiences.

First few steps:

New Exhaust or de-cat - stock exhaust won't get you very far, and is very restrictive

Speed limit defencer - a 110mph will quickly start to hurt you on the 1/4mile or certain autocross events.

JSPEC fuel pump/injectors - have to go at around 375bhp

Thanks, Good link.

So that would be something akin to a stage 1 tune (not that I like the whole 'stage' system, but it's just a blanket/widely recognised term)

What's after that? Uprated Twins? Large Single? How does the boost control system get affected?

Also when do you need to uprate the ignition? And injectors? Is the stock fuel rail able to cope? etc etc.

After BPU, it's then a shed load of money to go single turbo.

I'll run through the basic power steps, assuming you are starting with a complete stock 2JZ-GTE Supra running around 300-320hp.

1. First read this -> BPU. BPU requires, Exhaust, Decat Pipe(s), Restrictor Ring, Fuel Pump, Boost Gauge, Cooler Grade Spark Plugs and Fuel Cut Defender. This will allow the car to run around 1.2bar and make around 380-400hp (flywheel). Note: raising the boost pressure can reduce the life of the stock J-spec turbos.

2. After that you can add Cams, ECU, Boost Controller, Aftermarket Intercooler (side or front), Aftermarket Panel Filter. Each of those can be added individually, max you will be able to make with all of the above with the stock turbos is around 430hp. If manual you might find you also need a stronger clutch to cope with the power at this stage.

3. Then next (kind of) step would be hybrid turbos, these are stock turbo housings machined and fitted with larger internals. These will give up to around 450+hp (including all the previous modifications). It's a lot of money for a small gain, so is only usually considered if the stock turbos let go and need replacing.

4. If you want more power than that, then the only option is to completely remove the stock turbos, manifold, pipework, etc. and replace with an aftermarket single or twin turbo kit. Depending on the kit/turbo(s) you can have anything from 500hp-1000+hp. This is where is gets very expensive as literally everything needs to be replaced to support the power - fueling, electronics, cooling, engine internals, drivetrain, etc. etc. etc.

Also when do you need to uprate the ignition? And injectors? Is the stock fuel rail able to cope? etc etc.

Ignition wise, you'll need cooler grade of plugs at BPU levels. The stock ECU is fine at BPU levels. It's only once you get rid of the stock turbos that you need to run an aftermarket ECU, etc.

The stock injectors will cope at BPU levels (430hp), it starts to get marginal at Hybrid Turbo stage.

The stock fuel rail will support a smallish single turbo install if fitted with larger injectors ie. around 600hp. Above that I would replace with an aftermarket rail.

Good post Nic Spot on as always.

If you look on the Supraforums site, they give a break down of various stages of upgrade. It never really was adopted over here but they have BPU BPU+ BPU++ BPU+++, etc.

It really is a personal choice but doing one mod and seeing the result, then another etc, can be fun as you experience gradual increases in power over time.

edit missed Nics post, so the above may not be relevant.

Just to add to Nic's point one, this assumes the stock side mounted inter cooler is working efficiently. With car used in winter on UK roads and subject to salt corrosion, some SMIC's' will be as good as useless.

It's a fair point Termie, but the BPU 'Plusses' used in their original form on SF don't really make any difference to the engines power. E.g. cam and crank pulleys (BPU+) won't make any difference to the power unless other factors are involved. As far as I can see they are just terms used by traders to lead the gullible (or misinformed) replace items which aren't needed. Same things really with the +++ mods, e.g. an FMIC in itself isn't going to get the car making any more power, it'll only help if the original IC is shot - it's only going to restore the power to what it would have been with a good condition SMIC.

Edit - you edited after I replied, but we're saying the same thing, just in different ways

In Summary, see Nics post. BPU is stage 1, the next stage is mega money.

Oh yes I remember now, there was some legal wrangling regarding the ownership of the term BPU. Totally agree with your comments related to FMIC. Given the age of most cars now, anyone new to ownership setting out on the modification addiction, would be wise to check the condition of the SMIC as they will not get the best out of any thing they do if the charge is too warm. FMIC is not the only route to replacing the stick SMIC, there are good aftermarket SMIC's available, including that designed by Chris Wilson that are good for power levels up to 550BHP. If that level of power might be ultimate goal for someone, and uprated FMIC would be a very wise early purchase.

Good posts, Some good information to remember

Another thing that can be done to improve the car, not in terms of power, but it's drivability, is to make changes to suspension and have a full geometry setting carried out. These relatively simple things can totally transform the car.