Nobody mentioned the possibility that Honda could actually be underrating the HP numbers slightly with the 2.2 . With s2000 insurance rates skyrocketing lately, its entirely possible. When the larger 3.2 liter NSX engine was unveiled, dyno results showed it made a lot more than 10HP over the previous 3.0

My guess is that the new engine will make consistent >210whp. Time will tell however.

 

[QUOTE]Originally posted by Iceman
[B]My guess is that the new engine will make consistent >210whp.

 

does this mean the interior is two tone like the rx8 has? please tell me im not dreaming...

 

Larger displacement either means a longer piston, or larger head on the piston(more or less). Either way, thats more mass to control, etc. Without increasing all the parts(adding a lot of weight, less efficency) you have to decrease the redline to make it durable. IIRC Given the equation of HP = Torque*redline/5252 Therefore the HP is the same from more torque.
Correct me if I'm wrong.

 

I'm having trouble making that equation come out to 240 HP for the current s2000.

Torque = 153
Redline = 8900

5252 = Not sure what this is?

 

5252 I think is the RPM range when tq = hp on the dyno chart.

 

5252 is the rpm on the dyno sheets when hp and torque curves always intersect...
Anything else and the dyno sheet is as reliable as confirmed info we have of the 04 model at the mo...

anyways i suspect the 2.2 will result in much easier drivability in the low roms 3000-4000rpm is where the car really needs it. The engine might actually be heavier than stock.

Meh, bring on Todas 2153cc Stroker or the Feels F23C...

 

I have to belive they are under-rating the motor.

I also believe (although this is speculation on my part) they Honda has "stroked" the motor. This means longer travel for the same or very similar pistons. This should increase torque, but will not have a DRAMATIC effect on HP. Because of the extra travel, they must lower the redline.

I am guessing that with the gearing changes, and the added torque that the 2004 will be a little better in the 1/4 with most of the change being in the 60' time. I believe however, that it may cause some slower times in the auto-x circuit, mostly depending on changes to the suspension.

I am REALLY glad I stretched to get an '03 this year. Even if it turns out that the 2004 is faster, I REALLY like the 9000RPM redline. The styling it what it is, but I really like the characteristics of the the engine/transmission/suspension that I currently have. I can't imagine Honda making it better based on the reports we've seen so far.

 

HP = torque * rpm / 5252

Peak HP (the reported HP) is just the highest HP across the engine's RPM band. It's not necessarily at redline or where the peak torque value is. In fact, it's usually at a higher RPM value than peak torque because typically the HP gain from higher HP offsets the loss of torque, until the engine loses torque rapidly when it starts to lose its breath. In the 2.0 engine case, the 240HP comes from

240 = torque * 8300 / 5252

torque = 151

meaning the 2.0 makes 151lbs-ft of torque at 8300 RPM, which is pretty close to the peak torque of 153 at 7700.

If the reported numbers are accurate, the new engine makes 240 * 5250 / 7700 = 163lb-ft of torque at 7700rpm, which is a bit more than the reported peak torque of 161lb-ft. So there's either some rounding going on here, or the numbers aren't accurate.

Keep in mind this is all just the peak values. More important is the range at which the engine can produce high torque values. There may well be engine speeds where torque (and thus HP) is more than +5% over the old engine.

I haven't heard if it's been stroked or bored. I believe stroked engines produce torque more easily, at a cost of lower RPMs, but I'm not real sure.

 

It is a stroker by all accounts - and you are correct on all points. Strokers usually have less revs because the psiton wobble becomes more of an issue as the conn rod becomes longer. We are all still guessing, but it is fun nonetheless.