Kent 266 Cam in an 850

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ADO15
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Kent 266 Cam in an 850

Post by ADO15 »

Hello! I'm looking for any one who has any experience or advice for installing a Kent 266 cam in an 850. I am planning on sticking with my HS2 1.25" carb as well as keeping my cast iron manifold and single box exhaust system. Any thoughts and carb needle recommendations would be greatly appreciated! Cheers!

ohh..this is for my 1965 Morris Mini-Minor (Super De-Luxe)
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Re: Kent 266 Cam in an 850

Post by gs.davies »

I'm interested in this; planning a similar modification to my 850 when it comes back next year only with the cooper 997 cam.. I think the 266 is similar to the 997'd cam

Some period reports had that and a gas flowed head down as making a significant improvement!
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Re: Kent 266 Cam in an 850

Post by ianh1968 »

Think about having cam bearings installed - Didn't the 850 engines
only have a white metal bearing in the sprocket end?

Ian
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Re: Kent 266 Cam in an 850

Post by mk1 »

I have built a few engines of this type & have never found it necessary to fit cam bearings this is more when the block is to be used in racing. Although it won't do any harm of course.

If you are fitting a cam of ANY sort to an 850 you should be thinking about modifying the head FIRST. the head is by far the most restrictive part of any 850. This will of course not show externally but it will make a world of difference to the performance & tractability of the finished car.

The order I would suggest would be;

Head,
Exhaust / Inlet manifold, system
Carb (single H4 works very well)
Cam.

A cam on its own will make very little difference.
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Re: Kent 266 Cam in an 850

Post by gs.davies »

Normally I'd agree with the order of doing things, however, as the engine will be coming apart for a check over, reseal, repaint etc (not to mention seeing what state the gearbox is in..) I'll put it back standard with a view to adding a head/carbutettors/exhaust later. Probably going to try going along the lines of the Downton 850..
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Re: Kent 266 Cam in an 850

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Re: Kent 266 Cam in an 850

Post by gs.davies »

mk1 wrote:The 997 Cooper Cam was 252°

http://mk1-performance-conversions.co.u ... m_data.pdf
Sure this is what was used in the Downton conversion wasn't it?
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Re: Kent 266 Cam in an 850

Post by mk1 »

Downton used various cams over the years, but in most of the No's 4 & 5 conversions they retained the standard cam in the 998 Coopers & used the 510 in the S conversions.

http://mk1-performance-conversions.co.uk/dtn_45.pdf (1966)

http://mk1-performance-conversions.co.u ... _4-5_3.jpg (1969)

http://mk1-performance-conversions.co.u ... 5_1973.jpg (1973)

M
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Re: Kent 266 Cam in an 850

Post by woodypup59 »

ianh1968 wrote:Think about having cam bearings installed - Didn't the 850 engines only have a white metal bearing in the sprocket end?
Ian
Yes - That is what is said.

Check before you get the line boring machine set up that there is enough meat in the webs.

Also consider the oil supply - are the other two journals presure fed or just splash.
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Re: Kent 266 Cam in an 850

Post by ADO15 »

Thanks for your thoughts everyone! Here is a little more on my situation. My number 3 cylinder got a nasty hole thanks to a loose nut. (see photos) It punched a perfect hole in the piston. I guess it had worn itself down enough after banging around in the valves to slip through into the cylinder. How it got into the head in the first place is beyond me.

So this is why I am rebuilding my 848. My machinist recommended the 266 cam and also installed the 3rd cam bearing. After all the standard surfacing of the head and block and taking measurements; my compression ratio will now be 9.75:1 vice the standard 8.3:1 that was stock. I figured that with the new compression ratio and the new cam, I should start thinking about how to get this thing tuned properly.

I guess I am wondering if my original components (1.25" HS2, EB needle?, orig manifold, standard single box exhaust) will work fine with the new comp ratio and cam or if it would pay to just jump up to the HS4 1.5" carb and upgrade the manifold/exhaust systems now?

Thanks again for the thoughts!
Fred
the problem.jpg
ouch.jpg

See all the rebuild pics here: https://www.flickr.com/photos/bowsprit/ ... 721997304/
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Re: Kent 266 Cam in an 850

Post by gs.davies »

That looks painful.. Are you rebuilding with the standard piston?

Be interested to see what gains you get from that set up. Did you have it dyno'd before it ate
the bolt?
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Re: Kent 266 Cam in an 850

Post by ADO15 »

Yep, rebuilding with just the one standard piston replacement. Unfortunately, I've only had the car about 2 years and never got it on a dyno. I did ask my machinist what he thought of the engine and he said that the 40k or so miles on the odometer are most likely an accurate reflection of the mileage. Beaney (as I call my mini after the original owner; I have the BMC passport to service record) was well cared for. Shame about that nut!
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Re: Kent 266 Cam in an 850

Post by gs.davies »

According to the second owner of my car, it had been round the clock when he got it in the mid 60's and it went round again when he had it! I've never taken it apart somive no idea what I'll find when it does come apart! Still running the wet flywheel and oil fed primary though.
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Re: Kent 266 Cam in an 850

Post by mk1 »

That nut had been rattling round for a long, long time!
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