10 replies to this topic

[david036]

Hi all
Just taken engine apart. I have found that I have a 285 cam.

Is this a good cam? Whats its power band? is there a more aggressive cam??

Cam was in a 1275 engine. When rebuilt its going to be a 1293 ish engine!!!

[david036]

Or can somebody point me in the right direction to find out more about this and other cams!!

[KernowCooper]

Its a Piper Camshaft and listed for the A Series as a Ultimate Road Cam
Part No. Application Power Band Power Increase Duration Valve Lift Timing Full Lift Lift @ TDC with clearance Valve Clearance Inl Exh Inl Exh Inl ATDC Exh BTDC Inl Exh BP285 ULTIMATE ROAD 2000‑7000 14BHP 280° 280° 0.400″ 10.16mm 0.400″ 10.16mm 33‑67 67‑33 107° 0.088″ 2.24mm 0.088″ 2.24mm 0.012″ / 0.30mm 0.012″ / 0.30mm

What is the car used for as a more radical cam is likely to make a a narrower power band on the road.

Edited by KernowCooper, 04 January 2013 - 04:35 PM.

[david036]

Thanks for the reply KernowCooper. I now know what I have and what I'm comparing to!! Such a mine field of different cams, all with such minute difference!!
Mine is being used on the track not a road engine!!

[Cooperman]

Check out the Kent 296 for track use. It will give power to over 7000 rpm from about 3500 rpm with the right head and induction system.

[bmcecosse]

Aye -but the engine must be built to take the revs - which isn't cheap !!!

[david036]

Aye -but the engine must be built to take the revs - which isn't cheap !!!

Out of interest, how do you build an engine to take the revs??? How high revs are we talking here?? Most of the time we revving at a min of 8

[Cooperman]

This is a bit hard to follow. If the engine and a 285 cam why would it be revved at over 8000 rpm. It would run off the power curve well before that and if the engine had not been built at huge cost to rev to over 8k it would, by now, have blown up taking the transmission with it.
The only A-series engine for competition which needs to rev to over 8k is the 970 Cooper 'S' engine. I also not that the OP says that most of the time 'we revving at a min of 8'. If a 'minimum' of 8k, what are max revs then and why are such high revs needed?

[jaydee]

Wow you must have a very lucky crank and some very heavy valve spring to rev it all the at 8k
Good luck with the regular rebuilds

[david036]

Have found engine to be safeish at 8k. Its when it gets to just under 9 that we've had problems.
Have always been trying to bring the revs down, but have never managed it..... apart from getting it from 8.5 to 8.
Just can't seem to find the right 2nd gear!!!!!

[MJWarren]

If its a well set up properly built N/A motor the cam i would be using for race application for a 5 port would be something like the piper 310sp or a little bit less harsh the Med agsp, both can be supplied from M.E.D and power ranges from around 3500rpm - 8000rpm+