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Can anyone explain the duration to me??

Duration of a camshaft is how long it keeps the

Inlet/exhaust valve open for. So if you look af a 360* wheel and you have 260* cams, the camshaft has to go around 260* before the valve closes again. Lift is how far the valve opens as in height. So if standard camshafts lift is 8.5

And your aftermarket camshafts lift is 10.25

Then obviously the cam lobe is going to push the valve down open further by 1.75 which there for increase's air intake to in most cases create more horsepower. :)

Just a basic run down if you can't get your head around it I can be more thorough.

Cheers Josh.

which 260s did you have ? would be awsome if you have before and after dyno charts to see the difference between the two cams ?

There is no real difference loaded up on the dyno. I've seen a back to back, graph actually looks pretty close.

Same as -9s and -5s on the dyno, they don't look worlds apart in response or anything.

But the difference lies in the transient response or on/off throttle on the dyno and that's where things were noticed. Also dependant on the headwork that's actually been done, that compliments the cam setup, so it's no one singular thing

If the change was same setup to same setup and the only change was cams then it would been interesting to see the difference

I've seen on my 34 the difference from going to type Rs from type Bs and it was a fair bit, same peak power but every thing happened 800 rpm sooner give or take

so for my 6266 turbo (medium size single turbo) which already has a lot of grunt up top, would benefit from type R cams or there abouts, small duration 9.1 lift, to help spool and bottom end response

wonder why so many people go type b then

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