49 replies to this topic

[Cooperman]

With a 266 you can run a 3.1, 3.2 or 3.44 FDR. If running a SCCR box then a 3.44 would be best to cater for that high 1st gear. I built a 1275 Cooper 'Endurance Rally Formula' with a 266 cam, 1330 cc, 10.2:1 head, slightly gas flowed and based on an MG Metro head, RC40 twin-box centre exit 1.75" exhaust system, slightly improved alloy inlet manifold, etc, and I ran a 3.44 FDR in a standard ratio gearbox. It had 85 bhp at about 5700 rpm and, on the road, it was much nicer to drive than my 1293 'S' with over 110 bhp and a 286. The only time my 1310 rally 'S' was quicker was on a rally test when I used 7000 rpm and kept it 'on the cam'. If you look at the graphs for those 2 cams, the 266 has more 'under the graph' at normal road driving revs, say 2000 to 4000 rpm which is what matters. For out & out 'grunt' the 286 is my personal favourite cam so long as the driver is prepared to run at very high revs like 5000 to up to 7000 a lot of the time and be prepared to re-build it very often, but for a road Mini the 266 is a fantastically flexible cam giving very useable power from about 2000 rpm to 6000 rpm.

[crock]

Once again I ask people to reconsider what you are advising. A 286 cam in a car with 7 ports and dual Webers will be a different animal than a 5 port engine with a single Weber. You will get much better low end response. A 286 cam in an Alfa, a Cortina, or a Fiat with dual DCOE's is no big deal the street because a single port and carb throat per cylinder really broadens the power curve and response of the motor. That's why you pay the big bucks, its not all just for looks!

[Cooperman]

If fitting a 7 or 8-port head and Webers, then it is not being built for normal daily road use as the OP to this thread was intending. 7- or 8-port heads are quite rare and are used primarily for competition work where low-end torque is unimportant. Even then, maybe especially then, a low FDR will be fitted as such a competition engine will be revved hard, will be lightened and fully balanced, will have a strengthened bottom end and will be stripped very often for refreshing. My replies are intended to try to help the OP with FDR selection for his daily road car and I say again, a 286 is not really suitable for a road engine as, no matter how you set it up, peak power comes at 6400 rpm and to use the cam as intended those are the revs necessary. To fail to use those revs is failing to use the cam as intended by the cam designer.

[critchie2006]

With a 266 you can run a 3.1, 3.2 or 3.44 FDR. If running a SCCR box then a 3.44 would be best to cater for that high 1st gear. I built a 1275 Cooper 'Endurance Rally Formula' with a 266 cam, 1330 cc, 10.2:1 head, slightly gas flowed and based on an MG Metro head, RC40 twin-box centre exit 1.75" exhaust system, slightly improved alloy inlet manifold, etc, and I ran a 3.44 FDR in a standard ratio gearbox. It had 85 bhp at about 5700 rpm and, on the road, it was much nicer to drive than my 1293 'S' with over 110 bhp and a 286. The only time my 1310 rally 'S' was quicker was on a rally test when I used 7000 rpm and kept it 'on the cam'. If you look at the graphs for those 2 cams, the 266 has more 'under the graph' at normal road driving revs, say 2000 to 4000 rpm which is what matters. For out & out 'grunt' the 286 is my personal favourite cam so long as the driver is prepared to run at very high revs like 5000 to up to 7000 a lot of the time and be prepared to re-build it very often, but for a road Mini the 266 is a fantastically flexible cam giving very useable power from about 2000 rpm to 6000 rpm.

I've just ordered the MED SCCR gearbox with 3.44 final drive. So I'm definitely going to swap my cam for either a 266 or a 276?

[welshdan]

A mild road cam as suggested would be a waste in my mind with the 7/8 port head etc. If you were looking for a sensible road engine, next overbore size, sw5/266 etc, stage 3 head, good exhaust system etc

As the op has his heart set on the 7 port, i say make the most of it. As said peoples perception of what is acceptable is different. I live in an area with duel carridge ways and open country roads, i would not hesitate to use something such as the 286. If you live in a traffic choked city this may be different

The op needs to ask themselves what they really want from this engine. I would stop buying any more parts until you know.

The best bet would be to go out for a spin in someones car with these different cams fitted to see what each is all about. By talkibg about 7/8 port heads you suggest that you want good power, a nicely built 1380 with a 286 can be ballistic in terms of power for a mini. It will always be quicker than a mini with say a 266; there will be less low down though, but more mid/ top end grunt

[Cooperman]

I think I'm tempted to not reply to this type of thread in future where members of this forum are advised that race cams are suitable for road engines. Quite simply they are not, unless it is intended to drive around like a loony on the public roads. Again, no matter how driveable you might make a 286 at lower revs two things are true. The first is that a 286 at 2500 rpm will be giving less torque and power than a 266 at those revs. The second is the need to continually use 6400 rpm to make the cam work as it was designed to do, which will cause very high bore wear, be unpleasant on a journey and be horrible to drive in traffic. However, if that is wanted they just do it, but please don't come back on here with another post like 'my Mini is horrible to drive in traffic', or 'my 1380 needs a re-bore so does anyone have a spare 1380 block as mine can't be re-bored again'. Even when all this is done, as a road car it will still be no quicker on a journey than a standard road car like a Rover 25, Fiesta 1.4 or Mondeo TDCi. The Mini is still a 54 year-old design.

[KernowCooper]

Drive my 1330 with a 276 and then you will see for a road engine a 286 is what it is a race camshaft not a fast road/rally the 276 is just that.

I know of one chap down here who went down the 286 route in a road car and its coming out as his words were its to hard to keep the engine on the cam, so as Cooperman has already said the 286 is hard work to keep the engine in the power band, and no mattter how much you convince yourself you need a 286 in your new engine build, somewhere soon the novelty will wear off. There are a couple of members here who have a 286 and one even commented about dropping back to a 276/266.

[Pigeonto]

You need a 286 above 5000 and a 266 below.....so come on AC or MED, are you working on a vvt conversion? Would surely be the best mod for the A series ever. And no more debates "which cam"

[KernowCooper]

We will always have debates on which cam, as members join and ask the question "Which Cam" its just difficult sometimes explaining why the cam won't work in that application on a road engine to someone who does not have thew knowledge to fully understand the reasons why not, which is why they asked the original question.

As for VVT it wont ever happen now due to cost and the original design of the A Series Engine, only way is VTEC Mini !

Edited by KernowCooper, 22 March 2013 - 02:18 PM.

[Cooperman]

He just did. Dave said, quite rightly: "Drive my 1330 with a 276 and then you will see for a road engine a 286 is what it is a race camshaft not a fast road/rally the 276 is just that.

I know of one chap down here who went down the 286 route in a road car and its coming out as his words were its to hard to keep the engine on the cam, so as Cooperman has already said the 286 is hard work to keep the engine in the power band, and no matter how much you convince yourself you need a 286 in your new engine build, somewhere soon the novelty will wear off. There are a couple of members here who have a 286 and one even commented about dropping back to a 276/266".

[welshdan]

i still think that the op should try to get a ride in a 286 cammed mini, and make a desicion there. its down to individual choice. i would say that this cam is fine for road use - knowing it is going to give the power when its needed. though others will disagree

it could be argued that many aspects of this proposed build could be seen as overkill or unsuited to a road engine - the 7 port head, 1380 overbore, straight cut gears etc etc

in my mind if a 1380 overbore. 7 port head etc are to be used, then the best course of action would be the 286

otherwise if you are after a fast road engine, save a lot of cash and go for a 1293/next overbore, fast road cam, st3 head....

[Orange-Phantom]

As the OP is building a 7 port it sounds like his spec isn't too far off what I've got so here is my 10 peneth worth...

First my spec so he can compare...
Engine:
1380cc . Vickers-spec AKM 'works-spec' 7-port cast-iron cylinder head, built-in inlet manifold . Custom made Vickers-spec JE forged pistons, 10cc offset dish . JE Pro-Seal piston rings . Swiftune SW-10 Cam. vernier timing gear . Vickers-spec JKD 1.5:1 roller rockers . 36mm inlet valves . 31mm exhaust valves. Vickers Miglia-spec springs, guides . DKE billet crank . Arrow billet A+ rods . ARP bolts . Vickers Miglia-spec steel main caps . twin Weber 38DCOE. Custom made aluminium stub stacks. Custom made ITG air filter. Vickers throttle linkage . Vickers Miglia-spec engine breather system . Mini Spares HC water pump . Radtec alloy radiator . Facet silver top fuel pump . Rover electric cooling fan, standard plastic mechanical fan . Mini Spares pre-pump glass filter. Aldon distributor . Aldon Ignitor electronic ignition kit in distributor . Aldon Flame Thrower non-ballast coil . 10mm NGK C8E spark plugs . 8mm Magnecor silicone leads . Vickers-spec Maniflow exhaust manifold . Thermotec exhaust wrap . Maniflow custom mild-steel link pipe . Mini Delta polished stainless steel system, rear side exit, twin-box . Thermotec exhaust blanket on centre silencer . HEL 7-row performance motorcycle oil cooler with aeroquip hoses and connectors . KAD rose-jointed top engine steady . engine wiring sleeved with plastic tubing.

Gearbox:
Original Jack Knight Developments 6-speed dog engagement manual gearbox . straight-cut 1:1 roller bearing drop gears . centre oil pick-up pipe . two rose-jointed KAD rear gearbox steadies . one uprated Rover forward gearbox steady . JKD steel driveshafts . Mini Spares orange diaphragm . ultralight steel flywheel . Jack Knight cross-pin 3.1:1 differential

As I've said before the diff really needs to be a 3.4 or a 3.9 (esp as it's a six speed)! Although it's geared at the moment to do 70mph at just over 3000rpm in 6th but it's a little long in first at the moment. Not a huge issue but one to amend at a later date.

If I'm cruising below 2,800 the car still pulls okay, if you want the real power you have to be above that. 2,800 is when the cam starts to properly work.

I don't have to thrash the balls off it to have fun, my engine is still quite flexible so I can drive it sedately and it is fine cruising but I've got real power if I want it. Although you are always aware that she want's you to put your foot down and give it some beans! (Or is that just me)? The seven port definitely makes a-lot more torque which compensates for the low down deficiencies of this cam.

The thing is if your going for a seven port then your really making a statement of wanting and engine of substantial power!

If the OP is after all out power then I would suggest the Swiftune SW-10 cam over the 286 as its basically a 286 but tweaked to be more suitable for road use. It's also a more modern profile than the Kent Cam. (It's still made by Kent as well).

If my car was going to be a daily drive (mine is a weekend toy and only comes out in good weather) then I would not pick the 286 / SW-10 I would pick a 276 or for a better all rounder the Swiftune SW-05. It would then be more driveable lower down and ultimately more useable on a daily basis.

I know what Cooperman is getting at but I would say just because maximum power is at 6,800 does not mean I have to drive it all the time at or around that rpm. It may be what the cam is designed for but you could say the same of any performance vehicle where max power will be at +6,000 rpm.

It's all about compromise. Ultimately the OP has to make up his mind as to which one he is going to make.

Also it keeps getting mentioned that you will need to have frequent rebuilds of an Engine with a high power output. Surely if it has been built with the correct uprated and high grade components and balanced/lighted it will be up to the job and last? Also what components will need to be refreshed and at what mileage? I'm only at 2,000 miles so I hope it's going to last a bit longer .

[Cooperman]

High revving engines, and there is no point in using a 'lumpy' cam which only performs at its best at between around 5000 and 6500 rpm if you don't intend to regularly use those revs, wear out more quickly. So regular rebuilding is necessary. In particular the centre main is susceptible to high wear, even with a 4-bolt steel main cap. If the engine is used to the specification to which it has been built, an d there is not a lot of point in so building it if it isn't, then at a rough guess a 20,000 mile re-build is to be expected with all new piston rings, main, big-end & thrust bearings. A re-bore would likely be needed at around 40,000 to 45,000 miles which, with a 1380 may mean a new block. Whilst a 286 may 'run' from 2800 it won't 'pull strongly' from 2800. If you look at the cam graphs, the SW5 is producing about 80% more torque at 3000 than a 286. Having used the 286 in many, many engines and in a high performance engine with a 286 it doesn't pull properly until over about 4500 rpm and is strong from 5000 to 7000. Why is it so difficult for people on here to get the Kent Cams graphs up on screen and actually see the power/torque characteristics? They give the complete answer.

[oltonlad]

just to put a spanner in the works............everyone is going on about the 266 & 276 cams..........there are other cams out there as well, such as the newman/morspeed PH3 camshaft, i had a morspeed PH3 cam in my old 1330 with a stage 2 morspeed head and HIF44 carb, it had 92.8ft/lbs of torque at 3250rpm, on the same day as mine was being rollered there was another mini there with a 1310 slark engine which was fitted with a stage 3 head and a 276 cam, my engine out performed it in both BHP and torque, the mspd PH3 cam is very similar to the 276 but has less overlap lift which improves torque, my 1330 was a superb engine with that cam and i wouldn't think twice about using that cam again, its excellent and AC dodd loves that cam too!

Edited by oltonlad, 22 March 2013 - 10:54 PM.

[KernowCooper]

He just did. Dave said, quite rightly: "Drive my 1330 with a 276 and then you will see for a road engine a 286 is what it is a race camshaft not a fast road/rally the 276 is just that.

I know of one chap down here who went down the 286 route in a road car and its coming out as his words were its to hard to keep the engine on the cam, so as Cooperman has already said the 286 is hard work to keep the engine in the power band, and no matter how much you convince yourself you need a 286 in your new engine build, somewhere soon the novelty will wear off. There are a couple of members here who have a 286 and one even commented about dropping back to a 276/266".

I mean why he thinks it won't work...........and it isn't a race cam. ANYONE who's driven a mini with a race cam would know.......

A simple typo something your not guilyty of Sir! do I need to stand in the corner now ?