spookyp said:
It's just ridiculous to draw a definite line in the sand and say "1 hp more than 252 and the tranny will explode". It just doesnt work that way with mechanical parts...
No, it doesn't.
Parts fail according to a probability distribution. And Honda does not want parts to fail - under warranty or even afterwards. They want to keep their reputation for reliable cars.
Suppose the probability distribution looked something like this:
252 hp: < 0.1 percent of transmissions fail within 50K miles
253 hp: 0.2 percent of transmissions fail within 50K miles
260 hp: 3.0 percent of transmissions fail within 50K miles
270 hp: 8.0 percent of transmissions fail within 50K miles
280 hp: 15.0 percent of transmissions fail within 50K miles
290 hp: 25.0 percent of transmissions fail within 50K miles
330 hp: 60.0 percent of transmissions fail within 50K miles
(Please note again that I am making up numbers here. Whatever the actual numbers really are, the chances almost certainly rise with horsepower.)
I can see how, with that type of distribution, Honda would limit the engine power to 252 hp.
Note that the transmission doesn't
necessarily fail when you go from 252 hp to 253 hp. However, as power rises, the chance of failure increases.
Seeing these numbers, you might be willing to put a supercharger on, hoping that yours is one of the 40 percent that encounter no problems - and it very well might be. If the tranny fails, you pay thousands to fix it. With those odds, you might consider that risk worth taking.
Someone else might consider a 3 percent risk of failure - which is significant, if not probable (ask E46 M3 owners about a 3 percent risk of failure) - too much to take, and prefer to do everything possible to avoid a significant chance of incurring an expensive repair.
It's your car, and your risk. When you put mods on your car, the risk increases. And any failures caused by the mods are not covered under warranty.
Originally posted by RyRy210
I actually talked to Mark Basch about this and he told me that the simple I/H/E will be okay for the auto tranny.
So did I, and I thought he recommended against
any power modifications, including the "simple" I/H/E.
Originally posted by RyRy210
I believe the reason the engine is 252hp is a by product of tuning the C30A to better suit the characteristics of the automatic transmission.
I have heard one or two others say this - and they have all been owners of automatic transmission NSXs. I have never heard this from Honda engineers. Maybe it's true... or maybe it's wishful thinking on the part of those owners.