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The issue is the rods , people have lost motors at a lot less than 300bhp so as a tuner you have to look/tune on the safe side , The rods are powder forged and this adds a element of risk but the rods are the same as the FA-20 turbo motor in the late Imprezza so even Subaru are working these rods a little.

It sort of means rpm; rpm is a non-standard unit, so to do torque x speed = power, you have to use: Torque in Nm Speed* in radians per second Power in Watts You can do a calculation using other units (e.g. rpm for speed) but you have to use a conversion factor to correct it. To get more power, you would generally want more torque, yes. However you can also achieve it by changing where the peak torque occurs, depending on the engine characteristics. So if you had peak power at, say, 4000rpm, it might be that your torque drops off at higher rpms. You might be able to increase the torque at 6000rpm so that it's the same torque you previously made at 4000rpm: in that case your peak torque figure hasn't changed, but because it occurs at a higher rpm you'll make a higher power. It will mean that instead of making peak power at 4000rpm, you'd make peak power at 6000rpm. Hopefully that makes sense... If your car is tuned properly with forced induction, you won't be in a situation where you can add more power by changing the shape of the torque curve though. Peak power for these engines is very high in the rev range and the torque curve should be fairly flat in that region. Just my opinion here, but a GT86 with nearly 300bhp (as you'd get with forced induction) is pretty quick. To get that power, with appropriate suspension/brake upgrades, is going to cost £8-10k. If you really want more than 300bhp you'd be better off selling the GT86 and buying something else. (*As a note, "speed" is actually angular velocity, but I thought that was even more confusing!)

Power is torque x speed (with a multiplier if you're not using Nm and radians/sec), not torque x time. So, at a given engine rpm, if you increase the torque, you will also increase power at that rpm. When you see dyno graphs, they use rpm as the x-axis (along the bottom), and both torque and power on the y-axis. If you pick a certain rpm - say 4000rpm - the engine will make a certain torque, and as a result of that, a particular power. If you increase the torque at 4000rpm (by tuning), you'll have more power at 4000rpm.

I think so, yes. I guess the other way of increasing HP is to raise the rev limit but keep the torque relatively flat.

So are you saying that maximum chance of damage is at max torque (5000rpm) or when you’re full throttle at 2000rpm gear 6?

Martin, I'm interested in your experience with the uprated coils. Do you think the the improved driveability is down to the uprated coils, or just due to new items vs old/tired originals? Cheers!

boost isnt the issue it is cylinder presure that causes damage. peak cylinder pressure is at max torque , torque versus rpm is the issue that causes rod damage