Normally aspirated 2.8l engine will give 210lbft peak torque on high 98 ron fuel at 75lbft/litre which is about as much as is possible.
Bear in mind this is at peak torque, and maintaining more than about 90% of this at high rpm without some serious head work, cams etc is very hard, so lets be generous and say 189lbft max at 6000 rpm. This would give about 215hp at 6k revs, and if by some absolute miracle it can hold this to 6500 rpm, it'll get you 233hp.
If anyone believes that this is possible without the use extreme breathing mods and very high octane fuel (race fuel), you're seriously deluding yourself.
I'm sure you can get a dyno to prove it makes 240hp, but anyone who has any understanding of an internal combustion engine won't believe it.
One thing that anyone tuning a normally aspirated engine should be aware of is that you cannot increase torque by any significan margin.
Look at the attached table, and you'll see that 75lbft/litre is just about the maximum that is sensibly atainable from an engine. The peak specific torque output is a reasonable measure as to how well an engine breathes, and only cars such as the enzo, and the new M5 plus a few other exotics get over this 75lbft per litre, and they do it by having extremely clever cariable inlet geometary along with infinately variable lift and duration on their valves. Another good indication to how well an engine breathes is how far up the rev range maximum torque is produced.
You'll see that any high specific torque output engine tends to have a torque peak high in the rev range, and also produces high specific power.
Most engines don't have these features and are incapable of producing higher torque figures, and the shape of the torque curve is defined by the geometary of the head/valves, intake and exhaust.
By using free flowing exhausts and intakes etc, you can effect this ever so slightly (1 or 2%) at any point. The only way to make significant improvement is by moving the torque peak higher up the rev range using cams.
Look at the attached table, especially at specific torque output, of a variety of engines, and see how rediculous remappers claims of torque increases look. If a guy with a computer could do this, when all the automotive industry can't don't you think ferrari would be taking there cars to one of these mappers for some software?
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