8 replies to this topic

[G-Bob]

Cams ..... someone want to give me a quick overview? So camshafts are the doofers that spin round and open&close the valves yeah? What difference do they make to the engine characteristics, do they give you a power surge up the rev range etc.? I hear loads of folk saying that if you want to get bigger power then you need to go stage 1/2/3 cams and open up the engine etc. What is actually involved in changing them? Is it just a case of changing the cams or do you need to change/modify other stuff to go with it? (head porting etc) I basically want an idiots guide because I only ever tackle suspension/steering parts.

[TheRealVXed]

Should be able to just change the cams over with no other modification (other than re-map). Basically they move the power band up the rev range and alter the amount the valves open, how quickly and increase the overlap between exhaust and inlet opening. The more aggresive you go with the overlap the worse the idle will be until eventually it won't run at the standard idle and you have to move the idle speed up the rev range to compensate (hence why F1 cars idle is so ridiculously high!) Depending on the cam you choose will alter the shape of the torque and power curves. i.e a very agressive cam will have a relatively narrow power band but it will be greater. I don't know the profiles of the cams people are looking at though... I only have experience on A-Series (original Mini) engines. They can also be used to adjust the timing on inlet or exhaust or both.

Edited by VXed, 30 June 2011 - 03:10 PM.

[slindborg]

A properly setup engine with a 'lairy' cam (refering to both here) will idle fine and drive fine..... any that have been hard to idle and then like a snappy rocketship have been setup by a fucktard. For example the poxy 182 and thats got VVT FFS!!! Seems about the 'best' read that isnt total bollocks. http://www.deltacam.com/tech.php The cam lobe shape dictates the opening and closing amount and duration of the valve (opening can change a bit with the rockers but thats just a bit too far for now). Basically what you want/need is the largest amount of open 'time' possible, read time as piston travel. Big cam lift might not mean more power/air in if the opening time (duration) isnt suitable. All this stage crap about cams is well crap.... you want real numbers about lift/duration and you want the durations to be from the same levels of lift (usually 0.1mm) otherwise some cam companies can blag you on a longer sounding duration cam but in reality its just the same as an OEM one with longer ramp in and out which is duration but the valve is shut. I've had a cam made in the past that was pretty much rectangular as I wanted 310Degrees of opening time with a max of 10mm of lift because the head couldnt take any more mods to make the valves lift more.... That was really abusive on the valve train but feck it was good

[G-Bob]

Thanks for the info guys. Slindborg in doesn't like stage tuning shocker! I'll have a look at that link later slindy. So I could buy a set of piper "fats road" cams and just slap them in with no other mods then?

[slindborg]

Thanks for the info guys.

Slindborg in doesn't like stage tuning shocker! I'll have a look at that link later slindy.

So I could buy a set of piper "fats road" cams and just slap them in with no other mods then?

Depends if the management will cope with it... some will some wont.
get the cam specs and lets have a looksee

[G-Bob]

Thanks for the info guys.

Slindborg in doesn't like stage tuning shocker! I'll have a look at that link later slindy.

So I could buy a set of piper "fats road" cams and just slap them in with no other mods then?

Depends if the management will cope with it... some will some wont.
get the cam specs and lets have a looksee

These ones: Click here

[vocky]

the standard ecu can only really cope with the Piper regrinds, Schrick and the CompCams stage 1 stage 2 CompCams will run but power delivery is on/off stage 3 CompCams need a standalone ecu the z22se cams are quite easy to swap with the right tools, with the clam off it can be done in under 30 minutes, with the clam on it can take a couple of hours

[Nev]

Gobm, I assume you have an NA engine. If this is the case, cam changes on thier own won't dramatically change your car into a monster I'm afraid. You might be able to shift power bands up by maybe 10 to 20 BHP (at the expense of the low/mid range), so don't expect anything too much. If you are serious about more power you have to go down the forced induction route, ie S/C you car or turbocharge it (I would recommend either TBH). Then the cams would be just a part of the equation that delivers more power.

Edited by Nev, 30 June 2011 - 04:42 PM.

[Noodle1791]

Ive just had the piper cams fitted in mine and i love em so far. They do idle a little erratically but its going for a map to tweak it a bit. Cant say ive lost any mid range torque would say that it has increased if anything. Car jumps up to the rev limiter quite happily now so cant wait for my limit to be rasied up to 7k. Hopefully there may be some more horses up there? I recommend the Pipers for sure, but heck i would ive got them. If your interested you can check them out for yourself if your local and make your own opinions.