Aluminum flywheels consensus please

[FE 065]

There's been scattered threads on the use of Al flywheels. So many people seem to have taken their Al flywheels out.

Has anyone actually tried one at the strip? How did the AL flywheel work? Harder to launch, so ETs didn't change? Or launch wasn't a factor but no ET change - 'if' the flywheel was the only thing changed when comparing before and after..

For this thread, let's see if we can narrow down the replies to drag strip results-good or bad, on cars who's only change was the flywheel.

On paper it'd seem like a lighter flywheel would be a worthwhile addition.. If the engine revs quicker in each gear, it'd seem like ETs would drop..

 

[Andrew/USPWR]

Daily driver and road course.

I pulled it out of the GTS to help the low speed lurching.



2005 Silver SRT/10
2000 Steel Gray GTS (sold)

 

[mntngts99]

I just put in a Fidanza and on pilots or BFG's it's not bad at the strip. With M/T ET streets it's not a good launch. What you gain at the big end you give up in your short time. Right now it's a love hate thing.

 

[1TONY1]

Daily driver and road course.

I pulled it out of the GTS to help the low speed lurching.

Ditto

I didn't like it daily driving and I don't think it helped/hurt any at the strip.

 

[Tom F&L GoR]

A hijack, but perhaps to add perspective.

Imagine you're on the start line and an athlete runs up behind your car, timed to give you a big push just as the light turns green and you launch. Then they jump on the car and ride down the track with you.

A sprinter can't provide much momentum to help get you moving, but the sprinter doesn't weigh much either (and please think rotational effort of the spinning flywheel) and so the burden of carrying them down the track isn't much.

An offensive lineman provides much more momentum to get you off the line initially, but then you have to carry the extra weight (again, rotational effort) the distance of the track.

In road racing, where you have braking and accelerating, plus turning left and right, a lighter flywheel is a no-brainer. Anything that makes transients easier is a good thing. If you've ever seen a Champ Car or F1 flywheel, you'd think it was an ashtray. In drag racing there is only one dimension (acceleration) that is measured and you have that huge discontinuity due to traction at the start. So the flywheel issue is muddled by whether the tires stick or spin - can't you either spin or bog with either type of flywheel?

To finish up, a lighter flywheel is fundamentally highly likely to help once the car is moving. The hard part is figuring out the combination of parts beyond just a flywheel that gives you traction to get moving in the first place, isn't it?

 

[RedEnuf93]

I do like my 17lbs chrome moly flywheel.

For dragracing it would be stupid to keep it on... It serves no purpose.
It's somewhat difficult to get the car moving, fun to drive though!

Summary: At the track, curvy roads, sprints, its a great combo. For dragracing I would DEFINATELY put the stock 27lbs flywheel on!

For me its a love-hate combo too...

 

[FE 065]

I just put in a Fidanza and on pilots or BFG's it's not bad at the strip. With M/T ET streets it's not a good launch. What you gain at the big end you give up in your short time. Right now it's a love hate thing.

Really? You can't just tach it up a little more to overcome the additional traction of the M/Ts?

 

[Camfab]

I've never had one in a Viper, so I can only speak from my past experiences.

A) At the time I had one, 1991, Centerforce told me their standard clutch would burn up. The reason they explained was that the insert(steel) on the Al flywheel had a lower coefficient of friction. The cast nodular iron flywheel provides more bite. They built me a special reverse facing, dual friction clutch.

B) Even with steep gears and a Richmond five speed my light Camaro always chattered during street driving.

C) Al is not nearly as stable as nodular iron. The Al expands much more than a stock wheel. So What? well clutch engagement was always an issue. The Al is more likely to warp as well.

D) Yes, the motor revs much quicker under no load conditions, and seems much snappier.

It's part of my been there done that section filed away in my brain. The Viper stuff may be 100% better than what I had, but I will never put one on my car. If you really want the weight reduction, I would consider a cromoly unit vs. Al.

 

[MacManInfi]

We have one in our V8 Miata, and while I realize that things may differ a lot for the Viper, you'd also think that a V8 powered Miata would still be very easy to drive with a lightened flywheel due to the light weight of the car and extra torque of the V8. But it's a real trick to drive. You think you're giving it more revs than it needs but let out the clutch a hair too soon and it stalls instantly. Get over agressive with the throttle when you let out the clutch and it'll light up the tires just as quick. You have to give it lots of revs and feather the clutch for smooth acceleration.

It does feel incredibly snappy and responsive, but the lurching is also pretty bad. It's hard to keep a nice, coasting speed. It wants to either accelerate or decelerate.

At the end of the day, I think it's really cool in the Miata, but I've been thinking about it a lot and I don't think I'd like it in the Viper. The viper is incredibly easy to drive right now, and still retains the fun factor while doing so. I don't want to screw up that balance.

 

[JUCD VPR]

I was contimplating the same thing, BUT i steered clear from it because i do quite a bit of drag rading and i hear it isnt good for drag racing. I say if your looking at in towards drag racing, then do not get one, stick with the stock one and put that money into something different!

 

[FE 065]

I just put in a Fidanza and on pilots or BFG's it's not bad at the strip. With M/T ET streets it's not a good launch. What you gain at the big end you give up in your short time. Right now it's a love hate thing.

Really? You can't just tach it up a little more to overcome the additional traction of the M/Ts?

Or raise the tire pressure to give you the little bit of tire spin you want..?

Not so much planning on getting one as trying to narrow down where the complaints were, and if anyone seen ET reductions or done roll ons with friends with before and after results.

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ping pong ball cannon

 

[mntngts99]

I just put in a Fidanza and on pilots or BFG's it's not bad at the strip. With M/T ET streets it's not a good launch. What you gain at the big end you give up in your short time. Right now it's a love hate thing.

Really? You can't just tach it up a little more to overcome the additional traction of the M/Ts?

Or raise the tire pressure to give you the little bit of tire spin you want.

I'm still working on the Launch, adjusting presser and Rpm. So far my best 60' with ET is only a 1.61 and at 4700 rpm it still bogs off the line. I only have a few more races this year and will decide this winter if I'm going back to the stock flywheel.

 

[viper spray]

Mine works fine on the street and runs mid 10s at the strip with my 355s.