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dont really agree with that, with a CA you also have a larger gearbox in the middle of the car and a larger diff in the rear. so the weight balance would probably be pretty much the same
and the CA powered car will probably have bigger brakes so coule come up to the corner faster and still be able to slow down to a speed at which it could get around the corner
then it would make its way away from the corner a whole heap faster then the a series car

if your wanting the car to be fast roud corners id say your time would be much better spent one suspention work and brakes than it would trying to save some weight

Thanks Tom.

Just as a reference treaded race tires are around 6KG in a 185/60 13, add that with a 4KG wheel and you could indeed save 24KG total. Also the best way to think of unsprung weight is if you get tackled by 61KG "heavyweight" like me vs some 120KG guy named tiny..............keeping control of tiny is a lot more work. It's the sprung to unsprung weight ratio, an old Dodge Polara with a 50lb wheel rides so wheel over bumps because the car is 80 times heavier than the wheel. In contrast the 1200 is only 50 times the wheel weight so it's easier for the wheel to move the car.

Now as for wheels.............if you think of them like flywheels that needed to be speed up and slowed down it quickly becomes obvious why lighter wheels are what you want. Also rolling resistance is a big deal my old 125 Roadrace bike used a tiny 90/90-18 and when I raced a Miata in Showroom Stock I used a 10mm narrower tire for qualifying because it was worth 2 tenths, over the course of a 12 lap race they'd start sliding around two much and the time made up on the opening laps would be lost on the closing laps.

Finally on a 1200 with stock A Series, 12KG is equal to about 1 HP power to weight wise....................the cost of getting 100KG out of the car would be far more than simple installing a different camshaft and Weber DGV Carb or a GX set up. So over all weight isn't as big a deal as we often make it but yea you want to keep the wheel weight down. Oh if it's any consolation I've taken more than 50KG out of my car only to have the roll cage make it all back up.

Tom

Quess i,m just trying to make the best possible car I can with money I have,

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Yep, the Key is balance. you hafto hav enough rubber on the ground and enough brakes to pull you up but to much of Iether will start slowing you down.

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Sorry mate I was being too cryptic. I meant my A series powered 1000 is more fun to race than my CA powered 1200.

cool thanks, so the lighter the unsprung weight the better the road holding?

Unsprung weight is every thing on the impact side of suspension i.e. wheels, brakes, hubs etc etc.. and the heavyer this all is the harder it is for the suspension to hold it to the road when there's a bump or rugh surface.

That makes heaps of sense, but thing I don,t understand is unsprung weight, what it is and how dose this affect it....

yeh wheels are the worst place to add weight, the major one of unsprung weight making the suspension work really hard and it'll cause the tyres to struggle to keep in contact with the ground. then there's the rotational mass as well, rotational mass on the wheels will work the engine harder trying to accelerate and make it slower and once they're up to speed they're harder to slow down as well so your brakes are worked harder too. some lightweight 13's are the best way to go, and in my opinion 13's are the perfect size for a 1200
know what you're sayin about ca's and stuff as well, a car that handles is much more fun to drive. even though mine is a heavy dirty ca20e with barely 50-60hp atw i still lapped my mates 240hp atw celica best feeling ever passing him twice in one session