Although I know about how rotational mass affects acceleration, I'm a little lost on the issue of the 8lb vs. 10-13lb flywheel. How would 2lbs. make a difference in stop and go traffic?CowboyDren said:Well, I can't help you shop, but I think I may be able to help you keep from making a poor decision. Are you absolutely, 100% positive that you want to live with an 8lb flywheel, or is this a weekend-only car? If you have to live through stop'n'go traffic, 8lbs really frightens me from a drivability standpoint. I know that guys do it all the time, but there are also guys that commute in 11-second cars; are you one of those guys? I think that I'd personally be a little happier with a 10-13lb wheel, but taste is subjective...
CowboyDren said:Don't think of it as 2-4 pounds, think of it as a 25-50% difference!
For a street car, you want a big, heavy, bulky flywheel that stores lots of energy. The stock wheel is something like 17-19lbs, isn't it? An 8lb wheel is only 40-45% of this? You just lost a lot of smoothness in acceleration from a dead stop. Once the car's rolling, the lighter the better, but I spend a lot of time idling at a dead stop, so I have to think about these things.
I haven't driven an SR-powered car with an 8-lb wheel, but I've driven one with a 12lb (IIRC) wheel, and it was just on the virge of being comfortable. That car was an NX, which I'm pretty sure is still lighter than a P10, so 12 still sounds like a really good weight to me.
:-\ Well, kind of. I undestand the part of losing a lot of smoothness by going to a lighter flywheel. But since I have a power-robbing automatic, wouldn't a 10-12lb flywheel help improve the response and acceleration?:surprisedCowboyDren said:Consequently, it's not absurd to get a stock flywheel lightened down to about 14lbs or so, sometimes even less, depending on how much you trust your machinist. This isn't as good of an idea as, say, buying a midgrade light wheel such as a JUN Lightweight (as opposed to Ultra-Lightweight). This is because a lightened factory wheel is just a lightened wheel, while a lightweight aftermarket wheel is exactly what it was intended to be from the very start. Does that make any sense?