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Evening Chaps,

I have a MED built 1380 in my 65 Mini Minor. It is basically an ex track day, summer fun car that im putting back on the road. Ive had it 7 months.

When it was first built it had a Kent 276 in it. Then at some time it was changed to a 286 (i believe the 276 was too slow for the track!)

Ive driven it on the road myself and its not great around town or in traffic as we know its how a 286 is. So im thinking of changing it back to a 276 or maybe even a 266 or something else...any recommendations. ?

Is it something i should/could do myself....never done a cam in a A Series before. Ive done plenty of other bits over the years, Engines in n out, Head changes etc, so i know one end of a spanner from the other, but id really like to give it a go.

Your thoughts please and any tips more than welcome.
Cheers. Dicky.

It’s a simple job with engine out, only issue is if your engine is a solid walled block i presume you would turn engine upside down split from gearbox or remove head to get the cam followers in, actual installation of the cam and setting the timing is easy, I have only ever done 998 engines where the covers come off the back of block. It’s something you don’t need to be a trained mechanic to do.

I had a 276 cam and it was ok but fluttered at low revs. Changed it to Minispares Evolution cam and got much better response at low revs. A good cam!

Well, I guess it depends how lucky and careful you are...

With tappet chest cover engines you can change the cam and followers without pulling the engine out of the car, if you remove the radiator and bend the inner wing slats apart for clearance. This guy even did it on a solid wall block using magnets to hold the followers up, with the engine still vertical! https://youtu.be/cd1x-NQstsY

On a solid wall block you would be much better splitting the engine from gearbox so you can install new cam followers while fitting the replacement cam. It is far from ideal to use old cam followers with a new cam, but if you’re re-using a previous cam [or the engine has done minimal miles since new followers were installed] it’s much faster than stripping the whole thing down - and is what we would have done for ‘backyard tuning’ in the day...

So I don’t recommend it, but if you want to try that anyway, and ONLY IF the cam is a slot or pin drive (i.e. doesn’t use the spider drive insert, which will drop into the gearbox) I think you should be able to change the cam out with the transmission/flywheel all still attached to the engine. Here’s my train of thought:

Remove the spark plugs, rocker cover and the timing gear cover. Align the crank and cam dot-to-dot and lock the crank by jamming the flywheel ring gear at the starter motor hole with an old main bearing shell [or the proper tool], then remove the crank and cam nuts, pulleys and chain. Also take a note of their position [tippex is good] before removing the distributor and its drive shaft, and remove the mechanical petrol pump [if fitted].

Lay the engine on its diff / back so the followers are angled slightly upside-down and don’t fall into the gearbox, then remove the rocker shaft from the head so that all valves are closed and there’s no pressure on the push rods. You can also remove the rods if you prefer. Rotate the camshaft by hand two full rotations SLOWLY to nudge all 8 of the cam followers up into their recesses.

Undo the screws on the cam triangular thrust plate, and pull the cam out - wiggling around to make sure the cam followers all stay well out of the way. Slide the new cam in, remembering to lube its lobes, but make sure the peg/slot engages on the oil pump before you torque the thrust plate back down, else you’ll smash the back plate of the pump.

Fit the push rods if removed, and put the engine upright. Rotate the cam a few times, and make sure all the rods are moving properly with their followers, then re-fit the timing gear dot-to-dot. Torque the pulley nuts [you should check/adjust the cam end float with shims here too]. Refit the distributor drive and distributor using your tippex marks, and the mechanical fuel pump if present. Now refit the rocker shaft, remembering to back off the rocker adjusters first, and set the valve lash for the new cam.

Plugs in and reinstall engine in car, then run the cam for 20 minutes constant medium revs for the lobes to bed in. Of course, if you screw up and drop anything into the gearbox, you’ll have to split the box from the engine to put it all back in place at which point you should definitely fit new followers.

Do it properly, remove the box and change the followers. I bet you, the 286 have wiped some of them out.

Got a billet 286 in my 1275GT & did wonder how it would be in a road car as the past owner complained this car would not go up Hills.. i dropped car down to 10 inch wheels as he has 13 inch Wheels on it !!!.. Now its not that special in traffic but on a back road & on hills its a great drivers car .. just keep up the revs .. but then i hate shopping & me doing about 1,000 miles a year this Kent Cam should last a bit (maybe) .. only issue is the Wife has to be convinced why i am razzing around so i blame this 286 Cam

IMO it's always worth timing the cam in, using offset dowels as necessary, especially if you have the engine out - it's always good to know you've optimised it even if you never get to know the actual difference.

I've played with other engines (Lotus TC and Rover K) where it's been measurable and 4 degrees made a very noticable difference. Not sure if the A responds similarly but I would say it's good practice to optimise the cam timing or at least check it.

Thanks for the replies, interesting.

I should have said, it was a 1275 A+ Block...so solid back. Engine will be out of the car and the Box will be split to get the new Followers in.
Looking forward to it in a strange way....love a learning curve !!

Im sure i'll be back with more questions before i start and after....when its back in the car and Blown Up !! lol

Cheers all.
Dicky.