19 replies to this topic

[The Matt]

I dunno about the whole stage 3 or stage 2 thing, different specs for different companies etc.

RE the camshaft:

Basically your valves will have a 'peak flow' so it aint worth opening them further than that point. On a standard head it might be (as an example) 0.4". I guess if you are getting a flow tested head they will be able to tell you what camshaft is best. Then by opening the valves at a 1.5:1 ratio rather than standard (1.25:1 IIRC) you may be risking crushing the valve springs (hence the comment).

A modified camshaft will open your valves further for a longer duration, if the rocker ratio makes them open too far over standard, you may end up closing down your power band (by making it run lumpier at lower revs for example).

I would say your best bet is to speak to different head suppliers (Minispares, Minispeed, Morspeed etc) and see what they recommend camshaft wise.

[Dog]

Ahh I see

Might go for a SW5 cam then, and a 1.3:1 rockers..

But like you said, I will have a word with Morspeed, to see what he says.
The reason I am using a SW cam is because people rave about them all the time, so they must be good!

I was looking at a Kent 276, but got told the SW would be better!

[The Matt]

Ahh I see

Might go for a SW5 cam then, and a 1.3:1 rockers..

I aint saying it won't work well together (more that I don't know if it will or not)

I am using a Kent 286 with a stage 3 Minisport head and 1.5:1 roller rockers, I spoke to Simon at morspeed and he said that with the cam alone, driveability would start at like 2500 rpm, but with the roller rockers up top, it would mean that would be more like 3500 rpm.

I then spoke to a few guys on here that contradicted that, so I am gonna see how it goes really, then whip em off and swap em for 1.3:1s.

[Dog]

Ahh...

Does sound good, for open road pokeyness...

I was going to go for a stage 2 head, and 1.3:1 rockers, with a sw5 cam... but got told it won't be enough for the size bore!

So I am a tad confused atm, the reason I started this thread

[SCURVY DOG]

i am running a 1293 with a 276 cam bushed gt rockers gives just under 1.5

stage one head and a close ratio gt gear set and a 3.1 diff

is in this months mini world got 66.2 bhp on the rolling road at the wheels

but clutch was slipping so could not get a full reading

think the neddle is a baa will check later and am running a standard mg electronic

dizzy

i had a 3.4 diff in it before but felt like i needed another gear so put the 3.1 in it

pulls much better and once set up on the rolling road goes like a train as has

lots of torqe am running 12" wheels with low profile tyres

hope this info helps