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Hello, in the process of putting together a 1071 S engine and still considering the cam choice.

It came with a very good, genuine 649 cam and I am considering this or a 544. Can you still get hold of a very good version of this or am I better going for the modern version (I'm told this is a 286).

The rest of the spec is a lovely, gas flowed 163 and twin H4's.

The idea of the car is a period race replica/trackday car with thoughts of even building a appendix k out of it in the future and running it the 1100 class (but this could be a pipe dream yet!!)

Any advice on the cam choice ? and would I be building out of its classification?

Oh, and I havn't got 5k to get someone else to build it!!

I run a 286 in my 1070 Dave and am more than pleased with the results - if you want it to, revs to an indicated 8000 RPM in the gears with no bogging down through the rev range. Am running a 3.9 diff though.

Cheers, Niall.
PS might be worth you doing a search on here as cam choice for 1071 has been the subject of several threads in recent years.

i find that on a road car a 649 on h4's is too much - even with 1.3 rockers its gets massive stand off from the carbs when setting of normally, unless you tickle it away - a 544 would have been a better choice.

the 649 in the race car on the other hand is great

I had Swiftune/Kent grind me a 544 on a Metro cam a year ago.

My 1071 when i first built it was plus 40, original 544/707 cam, l/w steel f/wheel, lcb, very nice head 37/31 valves and worked original inlet with modified hs2's. It went very well , revved to 8000 no problem. The only problem i found was that with the tall first gear of a sccr box it fell 'off' the cam on very twisty uphill stuff and you had to abuse the clutch to set off on a hill.

When i rebuilt it in 2006 i put a sw5-07 cam in it but also forged 1.5 rockers which are a must otherwise the cam's a bit' soft'. The result was superb , it ticked over like a std 850 but gave a ultra reliable 85-86 bhp at 7150rpm with 66lb torque at 5100rpm. But don't be fooled by those high rpm's, it would pull like a train from 20mph in top gear right up to 100plus mph yet return 40mpg driven 'normal'. A lovely engine, just like a 'downton' ie , smoother, more ecomomical than standard yet much quicker. Driven an b-roads without revving it my mate said he had trouble keeping up in his focus tdci All depends what your going to do with it Dave, but if it's a bit of 'everything' only one choice i would think. on saying that i had a 266 in a 1071, got one in the 'orangebox' and that gives similar results, probably for less money.

Cheers Gents, I guess the question is now...how much is that Gen 649 worth? it has the extra drive on it (I presumed for a dry sump?) and is in great nick.

about £100 i would say if its in good nick (thats what mine went for on the bay)