Tommys86 said:
I can only see the steel flywheel for the S2 as well - that's not going to offer much as the aluminium one?
I say that but what are the trade offs, did you notice much Roger?
Guessing lighter flywheel, faster spin (revs quicker), better engine response, generally* acceleration is improved - but what do you lose?
*Thinking hills climbs (Spa) grunt? acceleration is worse?
Engine braking ability?
Gear changing - engine speed drops off very quickly when shifting gears?
That's a shame if for whatever reason they don't list an Aluminium fly for the S2, I'll find out for you...
I went from a 1260kg car (2.5 140bhp) to a 1010kg car (2.7 205bhp) so as you can imagine even though there was a
3.5 year gap almost doubling the power to weight ratio from 100 to 200bhp per ton was to say the least rather substantial !
Just changing the fly will give anyone benefits for the road and especially for Racing, how much difference just for this one component is very difficult to say? there are downsides though (Mostly for road) which I'll come to in a sec..
If you are ever considering a full Engine rebuild, I'd seriously consider a knife edged crank this along with several other components is what's made a massive difference to the speed that the Engine's RPM rises.
Approx a total of 9kg of Spinning metal was the total reduction (3kg off the 951 Crank / 968 Rods / Wossner pistons / Aluminium flywheel and all balanced and blue printed)
The Upside is the engine's peak BHP is reached in a faster time, the downside is a reduction in Inertia.
If you take your foot off the gas at 100mph my car will decelerate and slow faster than
any other 2.5 or 3.0 944/968. This for a regular Sunday drive / road car could be a pain as you'd have to keep the power on longer
before lifting off for a Motorway slip road or a roundabout. Also hills as you mention will need more throttle, as the "Hamster" revolving in the cage is not as powerful as the original!
The upside is the smaller Hamster Spins up quicker (A bit like a smaller turbo does compared to a larger one) so lighter parts
that are spinning up in your engine will get to a given rpm in a faster time and hence if you did a back to back from point A to B
the lighter engines internals will provide quicker results (Less time), this is like saying your car will be 1 second faster by the time it reaches the end of a straight (on a circuit).
The quicker decrease in RPM also allows for quicker gear changes because the gears mesh better with a marked decrease in gear speed (A bit like heel and toeing) so you can ram the stick out from gear and into the next as fast as humanly possible and it goes it very quickly and the rpm's rise again much quicker than a standard crank weight.
There's only one thing for it, tell your dad to contact me and I'll let him sample my car (And you when your next in NW)
which with my recent Dog leg gearshifter makes the changes even more faster & easier.
The danger is I'm 99% sure after this he'll want the same! even though it's 291cc less and only has 8 valves and not 16 like
your S2 i think it will be / feel quicker. If only I could be arsed to take it off the road , cage and extinguish it etc..and get my ARDS done, I'd join you on the track...Now that would be a great comparison (Skinny body 2.7 8v 924 v 3.0 944 16v)
R
] )
