Jonathan Dyer

iTrader: (5)

I have a T56 "retrofit" with the same gear ratios as a T5. I've always felt that since I changed the ring and pinion that I have too much low end torque. It's hard to accelerate the car from a stop without spinning the tires a whole lot.

I'd been wondering about stepping back from my 3.73:1 rear end gears to 3.42s. Then I thought why not lose some torque to a reduction in rotating mass?

I read a thread a while back though in which the poster said that a light weight flywheel would increase engine vibration. I would have thought the opposite, that it would mask existing vibrations somewhat.

Flywheel manufacturers tend to say that an aluminum flywheel is a race only part. Would I be foolish to consider going this route?

Thanks,
Jon

//<86TA>\\

iTrader: (15)

The issue with an aluminum wheel for .street use is that its so light it can make it had to get going from a stop. You can get liightweight steel flywheels too. They are heavier than the aluminum ones, but usualy still heavy enough to retain streetability. Obviously you need to know what yours weighs and see if you can find a lighter one.

Jonathan Dyer

iTrader: (5)

Thank you for replying so quickly.

The flywheel currently on the car is 25lbs. There is a 16lbs steel one available. With regard to it amplifying or masking engine vibration - would there likely be any difference?

Also, as this one is made from the same nodular iron material, must it be thinner to achieve the weight reduction? That might make for some issues with the throwout bearing - like needing to shim it away from the transmission face in order that it still fully engage the clutch assembly?

Thanks,
Jon

JamesC

iTrader: (5)

I'm using the lightweight GM version. I've notice no additional engine vibration. It will, however, slow down faster and as a consequence can make shifting a bit jumpy. A simple bolt-on with my application.

JamesC

Jonathan Dyer

iTrader: (5)

Hmmm...food for thought then. Thank you for your personal experience.
What sort of damper are you running at the other end of the crank?
Jon

JamesC

iTrader: (5)

Whatever was stock on the GM crate (350HO Deluxe), I purchased.

James

JekyllandHyde

iTrader: (3)

I run a Ram Alimunum Billet flywheel that is 18lbs with my T56. I think that 's a pretty good compromise. The stock LT1 flywheel is 20lbs while GM had a lightweight flywheel that was 16lbs. It does require more gas than a regular car with a heavier flywheel to get going and it's pretty easy to stall out, but the response is very very crisp. I had to get used to shifting faster though because the revs also drop a lot faster than I'm used to. I like it.

Jonathan Dyer

iTrader: (5)

Thanks for your input JekyllandHyde.
I think this is something I'll be trying this summer.
Jon