Lightweight flywheel? yes? no?

As part of my offseason rebuild, I was considering going with a lighter flywheel... any thoughts on using them in a full on race car? All my other race cars had them without much issue. Just thought I would ask...

I noticed a huge performance gain and the motor was much more responsive. Go with a smaller triple disc clutch as well.....you'll like it. Just buy a winch for the trailer.

A really worthwhile mod Eric. Only thing to think about is minimum flywheel weight required to achieve good launches if you have to do standing start sprint type races. If you go to light and have big sticky tyres you can run into issues with "bogging" down off the line. Otherwise, light weight every time.

Kel.

Ok, how about Electric Water pumps? I lost a WP belt and overheated pretty badly at my last race, was considering an electric pump to simplify things. MEziere makes a nice 55gpm electric bolt on pump...

Ok, how about Electric Water pumps? I lost a WP belt and overheated pretty badly at my last race, was considering an electric pump to simplify things. MEziere makes a nice 55gpm electric bolt on pump...

Have considered this mod but have stuck with the serpentine at this stage without issues (fingers crossed). Will free up some hp as well and have benefit of continued cooling in pits with engine switched off. Added complexity over a belt though.

Kel.

A lighter fly wheel and a small 8.5" (eg Quatermaster) clutch are worthwhile in a race car. As Brian said don't use it to get on the trailer! A bit of a PIA to shim and adjust though. If you are not racing hard or up for a few engine pull outs to adjust go with a "heavy duty" 10" street clutch.

My Porsche has a tripple disk 5.5" clutch and I don't even use it in reverse!

No experience with electric pump. We have 100's of hours on our Panozs w/o any water pump issues. I don't see this as a benefit.

Very easy to add a sending unit and big red light if u need it, ours are pretty cold blooded and never have overheating issues unless not properly "burped".

I just check the gauges in the straights. Very reliable cars, usually.

Electric pumps are common on drag race cars, but not so common on road race cars.

Any idea why the belt let go? We change every season and so far so good over many seasons.

Kevin
GTS and Porsche Cup Car

Fidanza 12.5lb Flywheel is sitting next to my desk!

Thanks everyone. Is it worth it to bring it to machine shop and have it balanced with the crank and rotating assembly?

Fidanza 12.5lb Flywheel is sitting next to my desk!

Thanks everyone. Is it worth it to bring it to machine shop and have it balanced with the crank and rotating assembly?

Absolutely Eric, everything that bolts to the crank from the belt pulley at the front through to the flywheel and pressure plate at the back end should be included in the balance (including all bolts and washers).

As Kel said everything that spins should be dynamically balanced (except clutch disk).

Rods and pistons are static balanced (usually weight matched).

A good shop will keep the balance data so you can re-balance a pressure plate or flywheel later w/o having to give them the crank. Sometimes these are just static balance so ask the shop how they do it. They will have index marks for assy alignment.

Cheers,
Kevin