Cam Kits?

[Captain Starlet]

allrate ppl,question time again,i no some one who has a 1.3 swift an got a twin cam kit for his car an its made a massive difference jus wondered if ne1 else cud tell me ne thing about em....

wot they do?

how much?

availability??

thanks alot folks

[Spartan]

I'm not sure how much a difference it would make with the 4E. Obviously you will see power gains, but at a very steep price. Basically your camshaft has lobes on it that open the valves to let stuff in and stuff out.

Aftermarket camshafts have different sizes of lobes, often larger than OE which will open the valves for longer. Basically by increasing valve lift you increase the amount of good stuff you can cram in. This often moves the powerband around as Cam's are generally really efficient at one part of the rev band (unless it has VVT or vtec). So you might increase power at high RPM's (likely in the 4E) but will almost certainly lose grunt at low RPM's.

Base price for a twin cam engine is around £300 for kit (hardly ever less than this) this will include replacement parts of the valve train as well. Kits normally include followers, cam lube and a timing disc.

Availiablity, hard one as I'm not sure. You can bet they will be quite rare though.

Cams rarely work to their best by themselves. For example, if you installed a set that increased your peak power. To make best use of them you would need a good intake, a high flow manifold and a decent exhaust system. A chip would be a good bet to get all together.

Hope it helps.

[nrgizerbunny]

its not really worth it on a 4EFE engine because it doesn't have that much power to start with its 75hp and already twin cam albeit an unusual arrangement (single pulley and two gear driven cams). I doubt you'd get much more than 10hp with a cam kit and it would blow your fuel consumption to pieces.

the cams open and close the intake and exhaust valves and as spartan said they are optimised at a particular RPM. when the engine speed increases they can't get the air/fuel in and exhaust gases out quickly enough so really you need an overlap between the valves opening.

to get round this there are two methods available, the honda vtec system (cam shifting), where as engine rpm increases the oil pressure causes a different cam to engage with the valve thereby altering the timing and possibly the lift (amount the valve opens). early toyotas used cam phasing where the cam would rotate 15degs and thus cause the valve to open slightly earlier, the disadvantage with this is you can't alter the lift.

the later toyotas with VVTI use a combination of cam shifting and phasing.

hope this helps mate

have a nice day

sanj