Steel or Aluminum Flywheel?
10-06-2008, 07:11 PM
#1
Melting Slicks
Thread Starter
Steel or Aluminum Flywheel?
If I am going drag racing 2 times a month is the aluminum flywheel worth the extra $500 over a steel flywheel with a new clutch? A buddy told steel would be better for launches at the track but the aluminum would be lighter.
Let me know your thoughts,
Andrew
Let me know your thoughts,
Andrew
10-06-2008, 07:48 PM
#4
Burning Brakes
Member Since: Jan 2007
Location: Dallas TX
Posts: 1,093
Likes: 0
Received 0 Likes
on
0 Posts
I'm pretty sure he means your launching RPM. If you are launching at high rev its going to be harder on your clutch/flywheel. So, if you are dropping it at or close to redline you should get an aluminum. If not, a steel one should suffice.
10-06-2008, 07:58 PM
#5
Melting Slicks
Thread Starter
if he meant launch rpms i won't be doing any crazy high rpm launches...don't have the ***** for that...haha
10-06-2008, 10:11 PM
#6
Race Director
Member Since: Dec 2006
Location: Fort Worth, Texas
Posts: 11,120
Received 2,054 Likes
on
1,306 Posts
I agree that a steel flywheel carries more rotational mass and will help w/ launching a car( especially at lower rpms), but you have 4.10 gears and a fairly light car so gettin out of the hole shouldn't be a problem and the aluminum will rev faster...I've cut a 1.64 launching at only 4k rpm w/ 4.10s and aluminum flywheel...one thing to consider w/ a big cam is that there is less "cushion" between engine/drivetrain and it will cause more "feedback" at low rpms cruising ie traffic
10-06-2008, 10:12 PM
#7
Le Mans Master
Member Since: Oct 2007
Location: Greater Detroit Metro MI, when I'm not travelling.
Posts: 6,149
Likes: 0
Received 10 Likes
on
10 Posts
Irrelevant. The flywheel weight affects LAUNCH RPM, not the RPM you shift at.
10-07-2008, 07:52 AM
#9
Melting Slicks
Member Since: Dec 2005
Location: sterling ct
Posts: 2,291
Likes: 0
Received 0 Likes
on
0 Posts
all things being equal from a roll two cars with the same mods - one with a steel the other with an aluminum flywheel...the car with the aluminum flywheel will walk away from the other car....
10-07-2008, 08:43 AM
#10
Melting Slicks
Thread Starter
hmmm...so just b/c it is lighter it will walk away or b/c it will rev faster?
10-07-2008, 09:07 AM
#11
Safety Car
Member Since: May 2005
Location: Corpus Christi Texas
Posts: 3,990
Likes: 0
Received 1 Like
on
1 Post
10-07-2008, 09:17 AM
#12
Safety Car
Spin a ping pong ball, then spin a bowling ball. Which takes more work?
BUT, for drag racing, once you get it spinning (at the launch) it has more stored energy and will launch harder.
Now roll that ping pong ball at something then roll the bowling ball.
10-07-2008, 01:17 PM
#14
Melting Slicks
Member Since: Dec 2005
Location: sterling ct
Posts: 2,291
Likes: 0
Received 0 Likes
on
0 Posts
i went with aluminum- a few years ago i think it was MTI that did a test - i believe it was the same car just changed from a steel to aluminum flywheel. the dyno print out showed how much quicker the car's engine revved..the quicker you can go through the gears the faster your going..
10-07-2008, 01:23 PM
#15
Melting Slicks
Member Since: Dec 2005
Location: sterling ct
Posts: 2,291
Likes: 0
Received 0 Likes
on
0 Posts
here is the link- dyno printouts and full story
http://www.vetteweb.com/tech/0407vet...ion/index.html
Dietary Horsepower
Seeking the Truth About Lightweight Flywheels
Die-hard racers and serious performance fanatics are always looking for ways to save weight in their street or track cars. They know that weight robs performance. It's not unusual to see carbon-fiber body panels, gutted interiors, and lightweight wheels on track and some street performance vehicles. Reese ***, owner of MTI Racing, is a die-hard racer. He is a former crew chief for a major Corvette endurance racing team and a SpeedVision (World Challenge) GT competitor, and he currently spends his time tuning customer Corvettes. He contacted Team VETTE with a wild idea--modifying both a brand-new ZO6 and one of his tuner ZO6s with a lightweight flywheel plus a high-performance clutch and pressure plate. Reese was convinced that we would see a nice bump in performance from both cars after such a change. Intrigued, we set up some test parameters. First, we wanted the cars tested on a drum-style chassis dyno to determine their rear-wheel horsepower. Next we required that each of the cars be pre- and post-dyno-tested on the same day. Reese agreed to our terms and to provide the cars and labor if we could find parts for the project.
Team VETTE has high regard for Fidanza products, so we contacted their Marketing Manager, Bob Sheid, with our idea. Bob was very excited about Reese's proposal and agreed to provide us with two of their latest lightweight flywheels. He also convinced us to install SPEC pressure plates and clutches into our test cars. Bob was so excited about our project that he decided to attend the installation along with owner Lou Fidanza to provide on-the-spot technical advice! We called Reese back and told him the project was a go. After all of the parts were delivered, Bob Sheid, Lou Fidanza, and Team VETTE met at Reece's shop in Marietta, Georgia, to start the project. As promised, Reece found a customer who volunteered his brand-new Commemorative Edition ZO6 for our test. We are not kidding about brand new! Denny Stradtman's beautiful new car only had a little over 700 miles on the clock. Our second test car is Reece's personal black '01 Z06 "development" car. This car has had its intake, heads, cam, exhaust, brakes, suspension, and wheels modified. It's fast and sounds bad.
Reese arranged to take both cars to a dyno before their modifications. First up was the new ZO6, which produced 357.3 hp and 351.8 ft-lb of torque on its third run. Water temperature was 191oF and oil temp was at 210oF. Outside temperature was 53oF. The runs were made in fourth gear from 2,000 rpm to 6,400 rpm, and it took 14 seconds for the car to reach its maximum horsepower. Now that we'd established a baseline, it was time to install the new parts in Denny's ZO6. Reese's crew consisted of himself, David Munder, Chris Harwood, and Jesus Garcia. In a blink of the eye, the center console, wheels, rear suspension, transmission, and torque tube were removed from the new ZO6. Next, the stock pressure plate, clutch, and flywheel were removed and weighed. The three factory parts hit the scale at 51 pounds. The new Fidanza 12.5-pound aluminum flywheel (PN 198571, retails at $439.00), and the 14.5-pound Spec Stage 1 clutch/pressure plate unit (PN SC091, retails at $299.00) totaled 27 pounds--a savings of 24 pounds of rotating weight at the crankshaft! The team installed the new flywheel, clutch, and pressure plate in record time, and they all fit perfectly. Three hours and ten minutes after the first wrench was turned, the crew had finished reinstalling all of the parts, and the car was returned to the dyno!
Fortunately our weather was holding and the outside temperature was 54oF for our repeat test. On the way to the dyno, we noticed a slight increase in clutch pedal pressure over the stock unit, but it was not annoying. Our best of three runs netted 366.6 hp and 360.4 lbs of torque--a gain of 9.3 hp and 8.6 ft-lb of torque. Maximum horsepower was achieved in 11 vs. 14 seconds with the stock parts, and maximum torque was seen in 9 vs. 11 seconds with the stock parts! Back on the road, Denny's Z06 revved a little quicker and required a lighter push on the loud pedal. We could feel the difference. Satisfied with our results, we headed back to the shop to make preparations for the next day.
The MTI team started the next day off by taking Reese's black, modified Z06 to the dyno. The outside temperature was 56oF, and three runs were made in fourth gear from 2,000 to 6,500 rpm. The third run produced the best readings with 437.5 horsepower and 376.2 ft-lb of torque at the rear wheels with the factory flywheel/ clutch/pressure plate. Water temperature was 193oF and the oil was 209. The car was returned to the shop to install the new parts. The team installed another Fidanza PN 198571 flywheel, this time with a SPEC Stage 3 Clutch with Hybrid Pressure Plate (retails for $699.00). The job took four hours because the long tube headers on this car are a tight fit and are difficult to remove. Back at the dyno, the outside temperature was 58oF, and Reese made three runs in fourth gear from 2,000 to 6,500 rpm. The third run produced 449.2 hp and 400.3 ft-lb of torque. Water temperature was 194oF and the oil was 210 degrees. This was a net gain of 12 hp and 21.10 ft-lb of torque. Maximum horsepower was achieved in 8 vs. 9 seconds with the stock parts, and maximum torque was achieved in 5 vs. 6.4 seconds with the stock parts.
At the conclusion of the tests, Reese shared his observations with us about installing the Fidanza and SPEC components into our test cars. "The important thing to look at in this test procedure is the time to speed relationship, not necessarily the increase in horsepower. Keep in mind the test device we used was an inertia dyno. A flywheel does not make any horsepower, but it shows up as a horsepower gain because you have reduced the inertia on an inertia dyno. So you need to look at the reduction in time to speed that was created by the reduction of inertia. We went from 14 to 11 seconds to 145 mph on the stock Z06. What that tells you is how the car is going to feel on the street. It is going to accelerate quicker to the redline."
And after all isn't that what we expect to gain from a good diet--more speed from less weight!
http://www.vetteweb.com/tech/0407vet...ion/index.html
Dietary Horsepower
Seeking the Truth About Lightweight Flywheels
Die-hard racers and serious performance fanatics are always looking for ways to save weight in their street or track cars. They know that weight robs performance. It's not unusual to see carbon-fiber body panels, gutted interiors, and lightweight wheels on track and some street performance vehicles. Reese ***, owner of MTI Racing, is a die-hard racer. He is a former crew chief for a major Corvette endurance racing team and a SpeedVision (World Challenge) GT competitor, and he currently spends his time tuning customer Corvettes. He contacted Team VETTE with a wild idea--modifying both a brand-new ZO6 and one of his tuner ZO6s with a lightweight flywheel plus a high-performance clutch and pressure plate. Reese was convinced that we would see a nice bump in performance from both cars after such a change. Intrigued, we set up some test parameters. First, we wanted the cars tested on a drum-style chassis dyno to determine their rear-wheel horsepower. Next we required that each of the cars be pre- and post-dyno-tested on the same day. Reese agreed to our terms and to provide the cars and labor if we could find parts for the project.
Team VETTE has high regard for Fidanza products, so we contacted their Marketing Manager, Bob Sheid, with our idea. Bob was very excited about Reese's proposal and agreed to provide us with two of their latest lightweight flywheels. He also convinced us to install SPEC pressure plates and clutches into our test cars. Bob was so excited about our project that he decided to attend the installation along with owner Lou Fidanza to provide on-the-spot technical advice! We called Reese back and told him the project was a go. After all of the parts were delivered, Bob Sheid, Lou Fidanza, and Team VETTE met at Reece's shop in Marietta, Georgia, to start the project. As promised, Reece found a customer who volunteered his brand-new Commemorative Edition ZO6 for our test. We are not kidding about brand new! Denny Stradtman's beautiful new car only had a little over 700 miles on the clock. Our second test car is Reece's personal black '01 Z06 "development" car. This car has had its intake, heads, cam, exhaust, brakes, suspension, and wheels modified. It's fast and sounds bad.
Reese arranged to take both cars to a dyno before their modifications. First up was the new ZO6, which produced 357.3 hp and 351.8 ft-lb of torque on its third run. Water temperature was 191oF and oil temp was at 210oF. Outside temperature was 53oF. The runs were made in fourth gear from 2,000 rpm to 6,400 rpm, and it took 14 seconds for the car to reach its maximum horsepower. Now that we'd established a baseline, it was time to install the new parts in Denny's ZO6. Reese's crew consisted of himself, David Munder, Chris Harwood, and Jesus Garcia. In a blink of the eye, the center console, wheels, rear suspension, transmission, and torque tube were removed from the new ZO6. Next, the stock pressure plate, clutch, and flywheel were removed and weighed. The three factory parts hit the scale at 51 pounds. The new Fidanza 12.5-pound aluminum flywheel (PN 198571, retails at $439.00), and the 14.5-pound Spec Stage 1 clutch/pressure plate unit (PN SC091, retails at $299.00) totaled 27 pounds--a savings of 24 pounds of rotating weight at the crankshaft! The team installed the new flywheel, clutch, and pressure plate in record time, and they all fit perfectly. Three hours and ten minutes after the first wrench was turned, the crew had finished reinstalling all of the parts, and the car was returned to the dyno!
Fortunately our weather was holding and the outside temperature was 54oF for our repeat test. On the way to the dyno, we noticed a slight increase in clutch pedal pressure over the stock unit, but it was not annoying. Our best of three runs netted 366.6 hp and 360.4 lbs of torque--a gain of 9.3 hp and 8.6 ft-lb of torque. Maximum horsepower was achieved in 11 vs. 14 seconds with the stock parts, and maximum torque was seen in 9 vs. 11 seconds with the stock parts! Back on the road, Denny's Z06 revved a little quicker and required a lighter push on the loud pedal. We could feel the difference. Satisfied with our results, we headed back to the shop to make preparations for the next day.
The MTI team started the next day off by taking Reese's black, modified Z06 to the dyno. The outside temperature was 56oF, and three runs were made in fourth gear from 2,000 to 6,500 rpm. The third run produced the best readings with 437.5 horsepower and 376.2 ft-lb of torque at the rear wheels with the factory flywheel/ clutch/pressure plate. Water temperature was 193oF and the oil was 209. The car was returned to the shop to install the new parts. The team installed another Fidanza PN 198571 flywheel, this time with a SPEC Stage 3 Clutch with Hybrid Pressure Plate (retails for $699.00). The job took four hours because the long tube headers on this car are a tight fit and are difficult to remove. Back at the dyno, the outside temperature was 58oF, and Reese made three runs in fourth gear from 2,000 to 6,500 rpm. The third run produced 449.2 hp and 400.3 ft-lb of torque. Water temperature was 194oF and the oil was 210 degrees. This was a net gain of 12 hp and 21.10 ft-lb of torque. Maximum horsepower was achieved in 8 vs. 9 seconds with the stock parts, and maximum torque was achieved in 5 vs. 6.4 seconds with the stock parts.
At the conclusion of the tests, Reese shared his observations with us about installing the Fidanza and SPEC components into our test cars. "The important thing to look at in this test procedure is the time to speed relationship, not necessarily the increase in horsepower. Keep in mind the test device we used was an inertia dyno. A flywheel does not make any horsepower, but it shows up as a horsepower gain because you have reduced the inertia on an inertia dyno. So you need to look at the reduction in time to speed that was created by the reduction of inertia. We went from 14 to 11 seconds to 145 mph on the stock Z06. What that tells you is how the car is going to feel on the street. It is going to accelerate quicker to the redline."
And after all isn't that what we expect to gain from a good diet--more speed from less weight!
10-07-2008, 04:09 PM
#19
Le Mans Master
Member Since: Oct 2007
Location: Greater Detroit Metro MI, when I'm not travelling.
Posts: 6,149
Likes: 0
Received 10 Likes
on
10 Posts
Actually for that matter if you think your stock car with a flywheel will hit 145MPH in 11 seconds you are going to be very disappointed too... You would need to me around 8 or 9HUNDRED horsepower at the crank to do that. And hook it all up.
10-07-2008, 04:10 PM
#20
Burning Brakes
Member Since: Jan 2007
Location: Dallas TX
Posts: 1,093
Likes: 0
Received 0 Likes
on
0 Posts