Donald125

A friend tested a light flywheel and a stock flywheel on the exact same setup (2g eclipse with a TD06) .
With the light flywheel it does spool up faster(not by TOO much) and rev way faster to redline once it started to spool.

USS

Lightweight flywheels make the engine work less to cause the same number of revolutions.

It's kinda like running small ports on a turbo-manifold. Smaller diameter tubing will decrease spool time (increasing velocity), but cause more backpressure in the system, correct? You'll probably spool the turbo faster, but overall your car won't be any faster as you're wasting energy?

sohcpwr

smaller ports (to an extent, you dont want them TOO small) will increase exhaust gas velocity and increase turbo spool. Kinda how if you port out the exhast ports in a cyl head too much, youll end up with a lag monster t25

surfer

heavy fly will get you to achieve maximum boost pressure lower down the rev range

BigD

Don't most lightweight pulleys no longer act as a harmonic balancer wich will screw you motor up?

sohcpwr

if your engine is built isnt it no longer internally balanced anyways??

Xgenturbo

It all depends on the build, if you use a stock honda crank and pulley you will be balanced, if you use some no name crank, some half assed crank pulley made on a lathe in pakistan by a guy who makes $0.50/hour then offcourse you wont have a ballanced engine.

A flywheel has nothing to do with harmonics, because that is what the pulley is for.

jinxy

i think hes talkign about the weight of the piston and the rod in a built engine.

91efate

a properly built engine is weight balanced meaning all rotating parts are matched winthin grams of each other ie. rods caps are weight matched,rods,pistons,,even bearing weight is taken into consideration. an unbalance motor will not run smooth or long for that matter.then the crank is balanced by adding or removing weight from the crank lobes to acheive a neutral balance. HONDAS ARE INTERALLY BALANCED. the flywheel has nothing to do with harmonically balancing the rotating assembly

psycho_vince

I agree, the flywheel, nor the pulley has nothing to do w/ balance either. The pulley is just that, a pulley, not a harmonic balancer. This is not a V8. There is no fluid damper on hondas. I see why cheapo underdrive pulleys that do not spin true can impact the bearings, but a quality one that is properly machined, and balanced to zero, will not blow your oil pump, or spin a bearing. Now, with that said, I do believe ATI or Fluidamper makes a real silicon filled harmonic balancer for Hondas. I dont know why, but Id assume that it is for the retarded high spinning race motors (10k rpm?), but I dunno. Some one elaborate on this?? Main point, an underdrive WILL NOT kill your bearings/ oil pump, as long as it is not a chepo pulley. (as far as Ive seen)