JB Racing aluminum flywheel worthwhile?

[alpinewhite318i]

Anyone here using a JB racing aluminum flywheel? Does it give you more power?

[gastephens]

It sure is a beautiful piece but it is WAAAY lighter than stock and therefore a pretty extreme change. The guys I know racing it say it really helps the motor rev much faster. Don't know how livable it would be on the street. Here is what you will experience:

Less inertia in the drivetrain, so:

Harder to change gears smoothly.

Harder to leave from a stop.

Harder to heel and toe downshift (easier to blip but harder to time the blip)

You will like it when when you are running up through the gears.

[dibo]

If you're not building a track car, I'd just get the stock fly lightened... TEP cuts about 30% of the weight out... I think mine is down to about 12 lbs and cost less than $200 (including shipping to/from San Diego and refinishing).

[dibo]

Incidentally, I do have a JB fly on my m50 powered E21... I didn't buy it (came with the car), but it's pretty sweet. Of course I have no frame of reference (never driven the car without it), so take it with a grain...

[rover1]

(nt)

[nbristow01]

the inertia from the heavier flywheel smooths out the motor etc. Just have a miss at idle with a light weight and boy will you feel it. I had mine lightened to abpout 13 lbs and really enjoy it. Kind of best of both worlds

[visionaut]

I run one in my DD and just love it. Disagree with other's "opinions", obviously - but I have one. NO 'smoothness' issues at all - spins faster & slows faster are nice pluses to me on an 'improved' motor/drivetrain. It was a mod one can feel right away - I think it's well worth it vs paying to lighten the stock flywheel. (had one of those previously).

Tom

[TobyB]

Does it give you more power?

Nope. Not physically possible. Power comes from fossil fuel.

However, it helps with revving faster in lower gears.

Agree with others that it's not really cost effective on a street car.

And if you don't lighten the crank, it's not even the bee's knees on

a track car

(but yes, it makes throttle blips much more fun)

t

[M3M3]

from a handling point of view...a lightweight flywheel takes a big chunk of weight out of the car...lighter is faster and stops quicker! :-)

[TobyB]

ooo arrr... no arrrrgyuuummment...

aluminum block, anyone?

hee

t

[visionaut]

Gotta agree with Toby on this point - it's not the best improvement/addition on a stocker for performance. And clearly - no more power.

But if you're building a significantly modded 02, and you're going for optimization, and have already done induction, ignition, top-end, bottom-end, plus drivetrain and suspension improvements - it's the better choice, IMHO than cutting corners at that stage with just paying to lighten a stock unit. i.e. you're already not on the economy curve ;-).

And hey, who says great performance isn't sweet on the street too?

Tom