67rally

iTrader: (5)

Can someone explain how the following camshafts would perform differently from each other? Basically just looking at what a change in duration will do vs the change in lift. Assuming all other supporting mods are in place. Thanks.

224/230 .605" 110lsa
224/230 .626" 110lsa
228/234 .605" 110lsa
228/234 .626" 110lsa

batboy

iTrader: (6)

It's more complex than that, you also need to know which lobes are being used, valve overlap, and other factors. If all else is the same, generally higher duration moves the hp peak higher in the rpm range. Shorter duration cams tend to have more low to mid range torque.

67rally

iTrader: (5)

Ok, so assuming all else is the same, at what point is the duration too low?

Any disadvantage to running a higher lift if the springs can handle it and the heads continue to flow better at the higher lifts? Any advantage to running a lower lift?

batboy

iTrader: (6)

Higher lift is fine as long as your springs are up to the task. Higher lifts do wear out springs quicker, like maybe needing to be changed out at 20k miles or so. If the duration is the same or lower than stock, then it's too low. Higher lifts on a cam that is the same duration as another cam usually means different type of lobes.

67rally

iTrader: (5)

Thanks for that info. I have .650 springs. Ported 243's w/single plane intake.

Stock LQ9 cam: 196/207 .467/.479 116 lsa

TT427

iTrader: (1)

You really need to know the actual valve events to fully understand how they would act, and the differences between them. Being a single plane intake, I believe their are cam designs that will run better than any off the shelf grind designed to use a factory, or factory style intake. May be a question you ask before making a purchase.

67rally

iTrader: (5)

It's going to be a custom grind, but I'm not sure what the design/lobes will be.

garygnu

different lobe designs have different lift rates.more aggressive ramp rates require more spring spring pressure to avoid valve float.talk To Patrick-G or Martin at tick for custom cams.cams effect dynamic compression and where the engine makes power,they control cylinder pressure.