Yeah, it was defintely a very interesting series with the RSX-S buildup.
The discussion was about performance gains from lightened flywheels, about which I opined. I think I actually DO understand most of the principles behind the flywheel. For instance, though I did not mention the dampening characteristics of a flywheel, I am not wholly ignorant of that function. I never even mentioned the role of the flywheel as regards the starter. And I'm not even close to "insisting" anything. I have not advocated that anyone get a lightened flywheel, let alone "insisting . . .that everyone should get one."82-T/A said:You're not understanding the entire principal of what a flywheel does. It's not just a device used for the starter.
Like I said before, General Motors doesn't waste 26 pounds of steel for absolutely no reason at all. There IS a purpose to this. If you want to insist that you know what you're talking about, and that everyone should get one, then go ahead.
Only reason why I'm being adamant about this is because this motor is a 4 cyl. It NEEDs as much low-end torque as it can get. The weight of the flywheel helps the motor build up torque through momentum.
I don't want to be mean, but, have you ever installed or replaced a flywheel? And have you ever gone with a lighter flywheel?js_euler said:And I still believe that hp and torque are NOT a function of the flywheel weight.
Let's try to be reasonable and accurate in our replies, shall we?
You are correct, they are not. But..... but it is a function of how much of the engine's HP and torque is transfered to the rear wheels under acceleration.js_euler said:And I still believe that hp and torque are NOT a function of the flywheel weight.
No argument here, LBJay, and well put. :agree:LBJay said:Accelerating a flywheel requires a certain amount of energy. That energy cannot be transfered to the rear wheels. A lighter flywheel absorbs less of the energy and allows more to go though to the rear wheels.
But there is no free lunch. Since the lighter flywheel takes less energy to accelerate it also stores less energy and it requires less resistance to decelerate the flywheel. That is the stalling at takeoff that faultline experiences. And why the engine revs drop faster.
Factory flywheel designs are heavy to smooth out the power pulses especially at lower RPMs and make it easier for the "average" drive to take off from a stop light without stalling the car or having to use excessive revs. With a heaver flywheel the engine decelerates slower allowing smoother shifting (up and down).
Because of gearing (torque multiplication) the effects of a lighter flywheel are much more noticeable in the lower gears.
Personally I would always do wheels first. But true lightweight 18" wheels are anything but inexpensive.jimbo said:Obviously both these mods can be done, but let's say a guy only wants to spend enough money to do one of these mods. Which one would you do?
Don't think it would do much for standing starts, but would probably help with shifting. But then again it probably negates part of the reason for the lighter flywheel.brentil said:Having throttle by wire with ECU controls on it could this possibly help the stalling issues with a lighter clutch? Say if the ECU is designed to keep the RPM's from dropping to low to quickly when between gear shifts?
The BBS wheels I refered to are $2,500 the set. That is serious money. But cheaper than Fikse's.LBJay said:Personally I would always do wheels first. But true lightweight 18" wheels are anything but inexpensive.
I currently have centerline forged wheel on my car, 17's, and they weigh 13#'s. I just checked the site , and there are some 5x110's , 17's for $159 each. It does not say the weight, but being forged, they will be light. That is a great price for forged wheels.jimbo said:The BBS wheels I refered to are $2,500 the set. That is serious money. But cheaper than Fikse's.
That's just cash outlay. If I ever trade in the car, I can put the stock wheels back on and still sell the BBS's on ebay for $2,000.
jimbo said:OK. So if you had to choose between only making one of the following 2 mods, which would you choose and why?
1. Lightweight flywheel (stock, 23lbs - lightweight 9.5lbs) = -11.5 lbs rotational weight
2. Lightweight wheels (stock, 23.6 lbs - BBS RGR, 10 lb) x 4 each = -54.4 lbs unsprung weight
Obviously both these mods can be done, but let's say a guy only wants to spend enough money to do one of these mods. Which one would you do?
Stock on the 06 MX-5 (17x7) are 17 lbs.jimbo said:What do the stock wheels weigh on the MX-5?