TeamSMS

I have heard that i have to get a flywheel & counterweight when doing the swap...but my question is...does it have to be a lightweight flywheel or could it be a stock s4 flywheel and counterweight?

Thanks for the help in advance

trochoid

iTrader: (6)

You always match the flywheel to the engine. You can use a stock S4 NA flywheel on an S4 NA when using an NA tranny. If you use the TII flywheel and clutch, you need a TII tranny. You can use an S4 NA flywheel on an S4 TII since the rotors and front counterweight are the same. This allows you to use any 1st or 2nd gen NA tranny.

TeamSMS

hmm...that answers all my questions...also how much does a lightweight flywheel really help? my motor will be stock pretty much...

trochoid

iTrader: (6)

Don't know, never had one, but a lot of guys that do swear by them.

Jeff20B

iTrader: (13)

trochoid, you've always ran stock flywheels?

trochoid

iTrader: (6)

Yep, too cheap and to many other mods to do first. I had a hard time swallowing the $300 ceramic clutch for the widebody, ( now $400), let alone another $400 for a light fly+ the CW.

Jeff20B

iTrader: (13)

You could have gotten a light flywheel and used a stock disc and pressure plate. I've done it and it works great.

TeamSMS

Im trying to decide if i want to buy a lightweight one or not...i might wait for when i replace the clutch as well to do the flywheel. Thanks for the answers trochoid!!

trochoid

iTrader: (6)

Not for the future hp plans for the widebody and some track use.

Jeff20B

iTrader: (13)

At least consider a Racing Beat light steel. It weighs 13 pounds by itself, it is compatible with 215 and 225mm disc and pressure plate sizes so it covers the entire range from '74 to '92 NA engines and fits '74 to '92 NA trannies. It retains enough mass to make daily driving in bumper to bumper pleasant while reducing enough inertia, compared to the stock flywheel, to really increase the fun factor.

PercentSevenC says "I can't live without my light steel flywheel" and so will you.

TeamSMS

yeah but if im going to buy a flywheel im going to buy a lightweight aluminum one....also if i dont do it now i can get my exhaust done 1st before moving back to the clutch/flywheel.

Jeff20B

iTrader: (13)

I think I'll make plenty of torque in the future with the 20B, and I already have the light steel flywheel ready to go. I just have to get the disc and pressure plate.

I don't think I'll need an aluminum flywheel because the last time I drove the 20B, it could really zing with the light steel. However if I happen to go through NA trannies like Coati Mundi goes through women, I'll have to upgrade to a T2 trans and a 240mm setup at which point I'll probably get another light steel unless I can find a cheap aluminum.

Jeff20B

iTrader: (13)

I don't know how much the Fidanza weighs, but it's probably around 8 or 9 pounds. Probably similar for the RB aluminum.

trochoid

iTrader: (6)

RBs are Fidenzas.

justint5387

iTrader: (1)

The aluminum flywheel makes driving on a road course and autocross a lot more fun, the acceleration off the corner is much better. I think if you are into drag racing... you want to use the stock one. I would get a light steel one if the is a daily driver, I believe it is the best compromise. I chose the aluminum one because I mainly drive the car on track or autocross.

Jeff20B

iTrader: (13)

Are you 100% sure?

This is a Fidanza (thanks blown7). It is only compatible with 225mm pressure plates.



This is RB. It is compatible with 215mm and 225mm with the long bolt kit which includes spacers to make up for the step.



It is possible that Fidanza makes the RB flywheel but I have no proof. I'll just keep calling it the RB flywheel to avoid confusion. So should you. Fair enough?

trochoid

iTrader: (6)

I'm not sure where I read it, but it was from a reliable source, probably in the 2nd gen forum. Granted, Fidenza may not make all of RBs flywheels, but I can't see RB making all of thier own for such a low production volume. I'm guessing they outsource them like many others do.

Jeff20B

iTrader: (13)

I think they actually make the light steel flywheels. The aluminum ones are probably outsourced like you said.

You know the cutouts on the flywheel for clearance between the three spring arm connections on the pressure plate? It looks like the Fidanza has three cutouts and the RB has six (you only need three). I have two RB light steels and one is missing the cutouts. I just tried test fitting a street strip pressure plate and the rivets are within 1mm of touching the upper rim. What happens when the disc wears and the rivits contact the flywheel? It goes from grip to slip real quick. Solution? Either have it machined which is costly or use a 215mm pressure plate or maybe a 225 if it has the proper clearance.

steve84GS TII

Ill echo that.
Ive run nothing but light steel flywheels since the 90's and Ill never go back to the heavy stockers.
Reason being,1st....the gains in acceleration in 1st and 2nd gear are very obvious and entertaining,even with a stock engine.
2nd.....even though the feel of the clutch and throttle is slightly changed when you are starting off,it becomes invisible after a few days.I havent had a stock flywheel in 10+ years,but my light steel flywheel "seems" stock to me.You get used to it, so there is really no comprimises except cost.

TeamSMS

yeah im going to go with a stock s4 flywheel and counterweight for now...but soon im going to get the fidanza flywheel and a better clutch.

rotarydude

iTrader: (2)

Jeff could you clarify this statement a little more you confused the he!! out of me. Which flywheel and what kind of machining? i am interested because i have a few of these

Jeff20B

iTrader: (13)

The left is a newer RB flywheel purchased in '03. It has the clearancing cutouts which allow any 225mm and 215mm pressure plates to fit. Of course the 225mm require the RB longer bolt set and aluminum spacers, but you already knew that. The one on the right was purchased in '01 along with a 215mm street strip pressure plate and a 215mm HD disc which has been out of stock for a few years now. I think you can still get the 215mm SS pressure plate.



When I tried to use a 225mm pressure plate on the older flywheel to the right, certain ones bottomed out on the rivits before even contacting the disc surface. Others would touch the disc, but with only like 1mm of clearance before the three rivits around the outer circumference of the pressure plate friction surface. With heavy use it would last maybe a month or two before it would start to slip as the disc wears down, contacting the flywheel's upper rim.

When I test fitted a 215mm pressure plate on the older flywheel, the rivits had at least 3.5mm, which is plenty for several years of use.

When I measured the cutout depth in the newer flywheel, they were around 3.5mm, so there you have it. The one on the left is compatible with both sizes while the one on the right is only compatible with 215mm stuff.

As for machining, it is hardened steel so good luck. I'll just stick with 215mm components on my older one and call it good.

Jeff20B

iTrader: (13)

The RB bolt set you will need for the flywheel on the left.

The one on the right just needs the six short fat bolts and crush washers to hold the flywheel to a rear counterweight, which can also be purchased seperately. Stock pressure plate bolts can be used, so no need to buy any for the 215mm stuff.

djessence

is depends on what you want to accomplish with the light flywheel. It makes daily driving a bit of a bitch but is great for track/autocross

Jeff20B

iTrader: (13)

Daily driving is easy. In some ways it's easier than a stock heavy flywheel.

The really light ones like the 8 pounders can get to you sometimes. The light steels are 13 pounds. Also the weight of the pressure plate can play a part. 215mm generally weighs less than 225mm.