9 replies to this topic

[dan-russell]

Hi can anyone help. Ive recently bought a kent 286 cam, but the other day there was a mini on ebay with a 286 cam (which i thought was a high lift cam) and 1.5 rockers. I just wondered if it was actuly possible.... Cheers all.

[Cooperman]

Yes, it's quite poswsible. In fact i have that on my '64 Cooper 'S'. It's interesting to note, however, that when I added the 1.5:1 roller-tip rockers i gained only 2 bhp at 6000 rpm and gained nothing at all below 5600 rpm. In fact, I think I lost a bit at the bottom end, but since it has a 286 cam it is always revving at over 3500 it's hard to tell.

[dan-russell]

Yes, it's quite poswsible. In fact i have that on my '64 Cooper 'S'. It's interesting to note, however, that when I added the 1.5:1 roller-tip rockers i gained only 2 bhp at 6000 rpm and gained nothing at all below 5600 rpm. In fact, I think I lost a bit at the bottom end, but since it has a 286 cam it is always revving at over 3500 it's hard to tell.

Fair point!! Just that i was curious as i thought it was high lift... So really by adding them, you dont actually gain much in the way of power? Im only saying this as its a race mini didnt think there would be much point in buying them for that little increase (if they could be ran together )
Cheers

[Cooperman]

With roller tip rockers the wear on the valve guides is reduced, despite the increased valver stem velocity, as the rockers act axially down the valve stem and don't apply side loads to the valve stem as the normal rockers do. That seems to be the only advantage when used with a hotter cam. With a standard cam it seems as though theyt do give a bigger net gain in top-end power.

[dan-russell]

ok cooperman, thanks for the help!!!!!!!!

[bmcecosse]

The 286 cam should be higher lift anyway - my advice is to NOT buy higher ratio rockers. The potential gains at high revs are more than nullified by low rev loses. And - they greatly increase the wear on all the valve gear.

[MRA]

The Kent MD range of cams where developed in conjunction with Kent and David Vizard ......... the whole range where developed for 1.5:1 ratio rockers.

Therefore using the 1.5:1 rockers with this cam will in fact bring out the best

[mike.]

But aren't you sacrificing what little low end driveability you had by adding rockers like that?

[Dan]

If you want driveability, don't put race parts on a road car. It may sound harsh but a race engine really isn't a road engine.

[MRA]

The MD286 cam is as close to being a race cam as you really want to go, on the road they work well in bigger engines ie 1330 upto 1459, any smaller and you lose bottom end power and of course driveability, any bigger and you lose the benefits from the 286 because you really don't want to be revving these engines too high, well not if you want to keep them for a long time

A 276 would be a better cam for driveability whilst still keeping decent mid and top end power............. however in a 1330 it would be a "toss up" between 276 and 286 me personally I would go for a 286 and after owning and driving several 1380's with 296 now that is fun cam on the road This will drive like a race engine so on the road using the gears is mandatory, driving along at tickover is almost impossible........ but it is fun until you hit traffic

Also on the subject the 276 right up the range benefit from a 3 into 1 manifold .... this is the type where all 3 pipes join just under the floor, this type extract more torque all the way up the rev range

Edited by mra-minis.co.uk, 06 November 2009 - 07:12 AM.