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-   -   which flywheel should i pick? (https://www.rx7club.com/1st-generation-specific-1979-1985-18/flywheel-should-i-pick-438145/)

SF@Rx7 06-27-05 08:46 PM

which flywheel should i pick?
 
i am thinking of getting a lightened flywheel for my gsl-se
i have 3 choice now

A, 15lbs steel flywheel with counter wieght from cp racing $350shipped
B, 16lbs steel flywheel with counter wieght from racing beat $372+tax+shipping
C, 12lbs aluminum flywheel with counter wieght from racing beat $455+tax+shipping

which one should i get
my SE is pretty much bone stock now
but will put the rb exhaust system in while doing the flywheel job

plz let me know if there is more flywheel to choose from
any input would help thx

Arockrx7 06-27-05 09:40 PM

I would not go too light. I choose option B. if the flywheel is really light the the rpms will drop faster, which I wouldnt want because of all the heel-toe shifting required to downshift/revmatch. I would also get a clutch to go with the new flywheel.

SF@Rx7 06-29-05 05:40 PM

anyone have any idea?
anyone have expenience on those flywheel?

84stock 06-29-05 05:48 PM

I run a S5 flywheel on mine and am satisfied.

blown 83 06-29-05 06:40 PM

I would suggest option B, if you must put a lighter flywheel on there. You will lose a good amount of torque by dropping it at the flywheel, but, it will spin up faster.

Eatdust 06-29-05 07:28 PM


Originally Posted by blown 83
I would suggest option B, if you must put a lighter flywheel on there. You will lose a good amount of torque by dropping it at the flywheel, but, it will spin up faster.

Yes and no....

The flywheel does not lose torque, but it does accelerate and slow down faster due to it having a lower reciprocating mass (momentum). This can cause problems in that the car will be more prone to a rough idle, and will be harder to get off the line smoothly, and as it has been mentioned it can sometimes be harder to change gears. On the up side less reciprocating mass = less drive train loss and faster accelerating in gear. So the car is actually faster, (slightly)

The motor doesn't produce any more power or torque with a different flywheel, however to drive it feels different.

I'd do it....once you've gone light you'll never go back...(with that said if you drive in lots of stop/start traffic I wouldn't....)

I would choose option a - based on cost....and it still has some mass so it won't be as hard to drive as option c...

You could also just have the std flywheel machined down and re-balanced... could be cheaper and it works just fine (all of my rally cars have been done this way!). Just remember it's not so much the weight of the flywheel, but where the weight is...ie if it is out on the edge near the ring gear it has greated effect than near the centre....

Cheers. :bigthumb:

91TII 06-29-05 07:31 PM


Originally Posted by SF@Rx7
i am thinking of getting a lightened flywheel for my gsl-se
i have 3 choice now

A, 15lbs steel flywheel with counter wieght from cp racing $350shipped
B, 16lbs steel flywheel with counter wieght from racing beat $372+tax+shipping
C, 12lbs aluminum flywheel with counter wieght from racing beat $455+tax+shipping

which one should i get
my SE is pretty much bone stock now
but will put the rb exhaust system in while doing the flywheel job

plz let me know if there is more flywheel to choose from
any input would help thx




I would say B or A. Also get a good clutch while your in there!

Fire85GSLSE 06-29-05 07:51 PM

I say B but A might be ok too.
I am running B on my car now with the S4 counterweight
(due to me having s4 rotors and housings)

It is different and the rpm's fall quick when changing gears.
If I had to do it over again I would probally stay stock and have mine turned down some. That was alot of money!

Now the full RB exhaust is worth the money and I love it!

blown 83 06-29-05 08:08 PM


Originally Posted by Eatdust
Yes and no....

The flywheel does not lose torque, but it does accelerate and slow down faster due to it having a lower reciprocating mass (momentum). This can cause problems in that the car will be more prone to a rough idle, and will be harder to get off the line smoothly, and as it has been mentioned it can sometimes be harder to change gears. On the up side less reciprocating mass = less drive train loss and faster accelerating in gear. So the car is actually faster, (slightly)

The motor doesn't produce any more power or torque with a different flywheel, however to drive it feels different.

I'd do it....once you've gone light you'll never go back...(with that said if you drive in lots of stop/start traffic I wouldn't....)

I would choose option a - based on cost....and it still has some mass so it won't be as hard to drive as option c...

You could also just have the std flywheel machined down and re-balanced... could be cheaper and it works just fine (all of my rally cars have been done this way!). Just remember it's not so much the weight of the flywheel, but where the weight is...ie if it is out on the edge near the ring gear it has greated effect than near the centre....

Cheers. :bigthumb:

Maybe I should have clarified that a bit. Eatdust is correct. The heavier flywheel helps the engine maintain, so to speak, the amount of torque at higher RPMs. With my combo, I didn't want the thing to be revving so quickly that I couldn't stay off of the limiter under the spray. I would still suggest "B" as an all around good choice.

jgrewe 06-29-05 08:15 PM

I liked my version of choice 'C' on my car. Rev's like a dirtbike, just took some getting used to taking off from a full stop. Why not just find a counterweight off an automatic at a junkyard and save yourself about $200?

pbrx7 06-29-05 08:16 PM

i went with c on mine. love everything it does to the car. only negetive thing i have to say about it is its a bitch to get the car moving if youre stopped on a really steep hill.

stilettoman 06-30-05 12:05 AM

Driveability with Light Flywheel
 
I just happen to have some interesting exprience with this subject. The silky smooth idle will go away with a light flywheel, but for reasons I cannot explain, the driveability is not much affected as it would be in a piston engine. I put a stock RX4 motor, a 4 port 13b, in a 1980 GLC and drove it over 100,000 miles with an aluminum Racing Beat flywheel. I towed my little ski boat, motor and trailer up the local boat ramps with it for two seasons and never had any trouble getting it started up the ramp. That same flywheel is now in my RX-7, 18 years later!

These cars are shown at www.cardomain.com/ride/646433

I recommend option b. I have no personal experience with CP racing, but I have read many horror stories on this forum about their poor customer service, people waiting for months to get their parts, etc. Racing Beat is reliable and have a good product. The steel flywheel gives you most of the benefit for less money. Of course I bought my aluminum flywheel for a lot less back in 1987.

SF@Rx7 06-30-05 12:16 AM

may go for option A due to the price

Fire85GSLSE 06-30-05 08:56 AM

Now this finally explains why I can't get my car to idle smoothly! This sucks!
If I knew that the lightweight flywheel was gonna effect my idle I would have never made that call to RB to order it.
Don't get me wrong I like the flywheel, but the rough idle and the high cost would have kept me away.

Guess now I can stop trying to figure out why my idle is bad.

Directfreak 06-30-05 09:48 AM

Racing Beat Steel Flywheel.

Zyrano 06-30-05 10:25 AM

I have a 'c' on mine and have no problems, love it.

Alvin

SPERRYsan 07-22-05 02:39 PM

Im currently putting a rebuilt 12a streetported with a lightened steel flywheel from tweakit.net


Sure the company is from Australia but the prices are great even with the shipping as long as your willing to wait a bit

my flywheel was 260 bucks with shipping and my own ring gear

all i need to do is find a counterwieght and I am set

SPERRYsan 07-22-05 02:40 PM

Im currently putting a rebuilt 12a streetported with a 12lb lightened steel flywheel from tweakit.net


Sure the company is from Australia but the prices are great even with the shipping as long as your willing to wait a bit

my flywheel was 260 bucks with shipping and my own ring gear

all i need to do is find a counterwieght and I am set

SF@Rx7 07-22-05 03:29 PM


Originally Posted by SPERRYsan
Im currently putting a rebuilt 12a streetported with a 12lb lightened steel flywheel from tweakit.net


Sure the company is from Australia but the prices are great even with the shipping as long as your willing to wait a bit

my flywheel was 260 bucks with shipping and my own ring gear

all i need to do is find a counterwieght and I am set

do you know the weight of the steel one?
it's real cheap
how long does it take for shipping?

Jeff20B 07-22-05 04:47 PM

I like the Racing Beat steel flywheels. My rotary powered MG and GLC have them.

SPERRYsan 07-22-05 09:48 PM

I was told the wieght of their "superlight steel" is about 13 pounds i think

shipping was 50 for 20 days

very good parts :bigthumb:


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