rx8magic

Hi i'm new to this forum, So please don't flame me. Just wanted to know more about flywheels.

First as flywheels go, is lighter better?
Why have counter weight ?
why rebuildable ?
What is the best flywheel for street/race combo?

Thanks for the help.

army_rx8

hmm well i would answer this but it would take a long time to type...and I'm about to go to bed :p

there have been a lot of discussions on this in the forum..while it may be a pain to read through all the threads to find your answers..you will become much more knowledgable in the process. :D good luck with getting your answers....if no one else helps out or you can't find the threads drop me a PM :D

oh and welcome to the cult

rx8magic

yeah i have spent a few hours searching and reading and it's starting to make my head hurt so i decided to post my questions to see if anyone can shine some light.

thanks for the welcome army. i'm finding it more and more difficult to not think about my 8!

ferragame

I'll try and answer this the best I can.

1) Lighter is better to a point. Too light and you can just about forget about making a smooth start from a stop.

2) Rotary motor's eccentric shaft does not have counter weights like a crankshaft so they are added to the ends of the shaft. The stock flywheel has the counterweight bult into it as part of the wheel. Look at a stock wheel and you'll see a large weight on the outside rim area. Its part of the flywheel itself and is not removable. Aftermarket (including Mazdaspeed) use the counterweight that is used for the auto and just bolt it to their flywheels.

3) Flywheels wear from clutch engagement. You can machine a flyweel smooth but eventually you might have to replace it. Rebuildable flywheels (usually done by replacing a bolt on part that wears) allows you to keep the light flywheel and just replace the worn part. Good in theory. I had one on my 93 Rx-7.

4) Personal choice. Talked to a very well respected mechanic a few weeks ago. He said the best bang for the buck for an 8 is a lightened flywheel. Said it made the largest difference for a one part change he has felt so far.

rx8magic

hey thanks for the info ferragame. My next question is what is a better flywheel material? Aluminum or Chromoly steel ?

brightnova

Sorry to hi-jack your thread a bit rx8magic. But I was hoping to tack a question onto your list. My question is: What does a lightened flywheel feel like compared to stock? From a drivers perspective?

Nemesis8

iTrader: (3)

Chrome-Moly is what the Mazdaspeed flywheel is made of. I wanted a stronger material, so that is what I chose. I'm not sure if it is better than aluminum.

As for the hijacker's question, the driver's perspective feels the low gears accelerate at a much faster rate. Its pure adrenaline :D

rx8magic

so i have one for chromoly does anyone else want to add their two cents ?

Nemesis8 as faster lower gears go for lighter fly would that be based on dyno or just the standard butt dyno ?

my only fear about picking a fly wheel is that i may choose the wrong one for my 8 and screw something up with the way the car rides.

Psylence

ChroMo is stronger than aluminum, but generally speaking the lightest flywheels are going to be made of aluminum.

Lightweight flywheels just make the car "feel" better.. engine is snappier, more responsive.. revs always seem to fall at just the right point between gears when you hammer on the car...

Granted, my experience is limited to Subarus, where I had first an 11lb aluminum flywheel, and after an STi motor swap went to a 9lb jun ultralight. I had absolutely no problems with a 9lb wheel on the street.. it was no fun driving in snow with a light wheel.. but who the hell would drive their 8 in the snow anyway? I never had any reliability issues in 30k miles with the 11lb aluminum wheel, for the record

As soon as I quit being so poor, a light flywhel is the first thing I'm buying for my '8. I just wish there were lighter flywheels available.. whats the M$? 16lbs? It's too much work/cash to replace a flywheel to only save that meager amount, as far as I'm concerned.

Nemesis8

iTrader: (3)

The MS has all of it's weight in the center. Plus, I did not want to rock the warranty boat just yet, so I had the dealer install it.

Here is a pic for you: http://www.nemesis8.com/images/P1010067.JPG

rx8magic

i talked to my dealer and they told me that a fly and clutch won't mess the warranty.

rx8magic

oh and today I decied to take the dive and ordered an ORC ogura racing clutch and flywheel and while I was at it I ordered a red carbon kevlar Varis hood. Now all that is let for me to do is wait ( long wait 8 to 12 weeks ) .

valpac

iTrader: (2)

There is. This is the one I'm going to have installed in my car. 9.75 lbs. Drove a friends car last night which convinced me.

http://monkeywrenchracing.com/act_pr...rx7_86_99.html

Jaguar_MBA

Racing Beat.....you can trust Racing Beat.

http://www.racingbeat.com/FRmazda4.htm

KYLiquid

I will end up going with the lightest flywheel I can find, the rule of thumb i always heard is never go lighter than half the stock weight, if you want a car that is driven in a lot of stop and go trafic, since to get a smooth start from a stop you will have to slip the clutch more.

I had an aluminium flywheel (Fidenza) on my miata, it made a world of difference (along with the ACT clutch) 1st, 2nd, and 3rd gears felt WAY better, and the car reved a lot quicker, that was a 9lb wheel (18 stock) it took about a day to get used to it, but then it was 2nd nature. The wheel was aluminium, but it had a chrome-moly friction surface that could be replaced. 45k miles on the flywheel with no problems.

Jaguar_MBA

You have to be careful because I beleive Prolite says their flywheel ways X lbs, but they do not include the mazda counter balance weight in that number....The racing beat weight I believe includes everything. Don't by the marketing hype, do the research.