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Topic: How to lighten a stock cast iron Flywheel (Read 2528 times) previous topic - next topic

How to lighten a stock cast iron Flywheel

How to lighten a stock cast iron flywheel



Start with your stock flywheel, In my case, 2.3L Turbo Ford



Its weighs in at 20.5Lbs

Lets see how much weight can be cut off….



Next is to remove the clutch plate alignment pins….



A slide hammer works well



Mount the flywheel upside down, on the flywheel grinder



 Start buy cutting the excess cast iron down to the ring gear..


 Once that was flush, I weighed the flywheel again, that reduced the weight by .75 lbs (12 oz) now 19.75 lbs

Time to thin the fat from behind the ring gear…



 each pass, this machine cuts only .005-.008 off…




 the final weight is now 17.75 Lbs 

I removed a total of 2.75lbs…. This should help the engine rev a bit faster, with out giving up too much torque..
1985 TC (yet another one) Fully loaded
has 225k mile  still with the factory head gasket






84  Turbo ranger  Daily driver  ($800.00 Ebay deal)
          volvo FMIC and more getto rigging than the law should allow

How to lighten a stock cast iron Flywheel

Reply #1
can someone who has done this on a street driven car and has some drive time with it shed some light here as ive been told to NOT lighten a cast iron flywheel for any reason, perticularly if you dont know what your doing?
"Beating the hell out of other peoples cars since 1999"
1983 Ford Thunderbird Heritage
1984 Ford Mustang GT Turbo Convertible
2015 Ford Focus SE 1.0 EcoBoost

How to lighten a stock cast iron Flywheel

Reply #2
:rollin:
yeah,, tell my left eyebrow that!!!
20 stitches later working under the bronco.

Anyone know how much a those f150 5speed (1991 or so) flywheels weigh?)

 hurt coming straight down on my head,, ring gear first lol.

Had to change ring gears twice before i figured out someone used the wrong flex plate...modified the AOD flex plate to accept the standard starter.

what a bitch.

How to lighten a stock cast iron Flywheel

Reply #3
Try a 345 IH flywheel.  Knocked me dizzy for a few minutes.

Good friend of mine's dad balances flywheels and cranks for a second job for the local dirt trackers and such.  key word is balance here.
1987 TC

How to lighten a stock cast iron Flywheel

Reply #4
Isn't the easiest way to lighten a 2.3 flywheel is to replace it with one from an escort?

Knew a guy that lightened his flywheel by drilling holes in it.  He didn't seem to like his feet that much.  Your way looks better.


Ductape91,

the flywheel "stores momentum"*, which makes it easier for a driver to move from a standstill in a car/engine combo like the TC.  The tradeoff is the cost in engine acceleration.  (*don't use this explanation in front of your science teacher)

The only car I know of from the factory without a flywheel is the McLaren F1.
__________________
Twin '85 TCs
White/ Grey 2-tone
#1 (left): undergoing top-to-bottom rebuild     
#2 (right): DD, power everything (sorta)
[SIGPIC][/SIGPIC]

How to lighten a stock cast iron Flywheel

Reply #5
Don't you have to have the flywheel rebalanced?
88 Thunderbird LX: 306, Edelbrock Performer heads, Comp 266HR cam, Edelbrock Performer RPM intake, bunch of other stuff.

How to lighten a stock cast iron Flywheel

Reply #6
the last 4 flywheels I have had balanced after lighting them were out about 2 grams, the Interal balanced engines  (most 4 cyl) do not seem to have issues as much as the external balanced engines ( 302 350 ect)

you have to be carfull of where and how much you remove so not to weaken the flywheel so behind the cluch disk you tend not to cut much.

yes you can replace the flywheel from a 2.3 with an escort, but you have to drill new clutch plate mounting holes.
1985 TC (yet another one) Fully loaded
has 225k mile  still with the factory head gasket






84  Turbo ranger  Daily driver  ($800.00 Ebay deal)
          volvo FMIC and more getto rigging than the law should allow

How to lighten a stock cast iron Flywheel

Reply #7
http://www.streetfire.net/video/Trans-AM-Clutch-Explodes_727191.htm

That video is about enough to convince me never to mess with a flywheel.  His was just the pressure plate, but I like my toes.  Granted the kid was an idiot.  But still, wow.
My car is a gravity hybrid.  The gasoline engine gets me up the hills, and gravity gets me down.

How to lighten a stock cast iron Flywheel

Reply #8
wow and they were laughing bout it like it was a huge joke.
2001 Buick Regal LS (DD):hick:

Got that fox rash again!

-Resident smartass! :ies:

- Don't listen to the naysayers. For every person who actually helps with your project there will be 10 who will discourage you all the while thinking that they are helping. 99% of all people have good intentions. That doesn't make them right.- XR7 Dave - SCCOA.Com

 

How to lighten a stock cast iron Flywheel

Reply #9
Quote from: t3skidoo;310599

The only car I know of from the factory without a flywheel is the McLaren F1.




that pic is not a McLaren
1988 Thunderbird sport
2004 Ford F150 Lariat
2008  Chevrolet Cobalt Sport
2007 Suzuki DR-Z400S dual sport/Supermoto
1988 Thunderbird LX - sold
1988 Mercury Cougar XR-7 with GST kit - gone

How to lighten a stock cast iron Flywheel

Reply #10
yep the driver is lucky.....

but I am not saying to do this on a 700+hp engine..... this would be ok for one up too  maybe 400 hp and a red line of about 7000 rpm
1985 TC (yet another one) Fully loaded
has 225k mile  still with the factory head gasket






84  Turbo ranger  Daily driver  ($800.00 Ebay deal)
          volvo FMIC and more getto rigging than the law should allow

How to lighten a stock cast iron Flywheel

Reply #11
Quote from: t3skidoo;310599


The only car I know of from the factory without a flywheel is the McLaren F1.


i understand what a flywheel does, that much i understand.
i was told to not lighten a cast iron flywheel because they are more likely to crack and explode from heat stress and shock(dropping the clutch)even on low powered motors.
im no expert so figured it wouldnt hurt to ask.


also im sure the car posted was a pagini zonda :P
"Beating the hell out of other peoples cars since 1999"
1983 Ford Thunderbird Heritage
1984 Ford Mustang GT Turbo Convertible
2015 Ford Focus SE 1.0 EcoBoost

How to lighten a stock cast iron Flywheel

Reply #12
DOH! that's what I get for posting just before sleepy time.



Better?
__________________
Twin '85 TCs
White/ Grey 2-tone
#1 (left): undergoing top-to-bottom rebuild     
#2 (right): DD, power everything (sorta)
[SIGPIC][/SIGPIC]

How to lighten a stock cast iron Flywheel

Reply #13
What an idiot,620hp i think not.
You could plainly tell he was slipping the clutch to max rpm,what did he expect.
It's only gonna get so red lol.

How to lighten a stock cast iron Flywheel

Reply #14
well...... some people have more money than sense
1985 TC (yet another one) Fully loaded
has 225k mile  still with the factory head gasket






84  Turbo ranger  Daily driver  ($800.00 Ebay deal)
          volvo FMIC and more getto rigging than the law should allow