cylinder head casting numbers.

Post by **XDB** » Fri Feb 08, 2008 2:13 pm

Can anyone tell me please what the casting numbers CAM 4810 on a cylinder head purporting to fit a 948cc engine means. It has the later solid rockers. It has a 9 hole stud pattern, heater take off and temperature sensor orifice. It also has the by pass hose spigot. What engine will it be from.

Post by **MoggyTech** » Fri Feb 08, 2008 2:48 pm

That number refers to an A+ head, probably from a mini.

Post by **XDB** » Fri Feb 08, 2008 5:46 pm

Thanks MT any problems fitting it to my 948cc minor, the valves are the same size.

Post by **MoggyTech** » Fri Feb 08, 2008 6:31 pm

No problems at all as far as I know. The only changes I am aware of on the A+ heads, was the fitting of proper type valve stem oil seals. Top hat type, with a spring around them. BMC eccosse is the cylinder head expert though, and may know of a few other changes.

Post by **XDB** » Fri Feb 08, 2008 6:38 pm

Yes it has that type of valve stem oil seal.

Post by **Matt** » Fri Feb 08, 2008 8:12 pm

It will fit perfectly well, the valve sizes may be the same but the porting is much worse and you will lose power. You would do better to fit a 1098 head with the slightly bigger valves and better porting

Post by **XDB** » Fri Feb 08, 2008 8:21 pm

that's a shame Matt, its unleaded, and I got it cheap, is there anything I can do to imrove the porting.

Post by **Matt** » Fri Feb 08, 2008 8:26 pm

Not a lot... if the unleadedness is important too you put it on and see how it performs.

I have put a CAM4810 down a refuse chute on the 9th floor (it made a nice noise when it hit the bottom) because its a poor head

Post by **XDB** » Fri Feb 08, 2008 9:47 pm

Right Matt, whilst I am on a roll (in rubbish) I have another head a 12G 202 is this one any good?

Post by **bmcecosse** » Fri Feb 08, 2008 9:50 pm

Yes - it's the same as an original 948 head, no better or worse porting wise, but not as good as a 12G202 head - or a 12G295 - or a 12G940 in order of 'betterness'! As Matt says - if you want unleaded and not bothered about extra power - then it will be fine on a 948. Used on a 1098 there will be some power drop. I too have given these away - sadly no big drop to play with!

Post by **XDB** » Fri Feb 08, 2008 10:10 pm

Oh bu@@er, the 12g202 isn't unleaded, I know I am flogging a dead horse, but how much power loss will the cam 4810 cause, I am only a fair weather driver, the furthest I will go will be to the National Rally in Leicester, I am just fed up of faffing about with additives. I am considering marrying a 1098cc box as well, will this make the situation worse. Lastly there is a company local to me who does unleaded mini heads at a good price, apart from the ones Matt mentioned which other ones would be suitable? Thanks for your advice, I am slowly working back through all the mechanical posts, fascinating stuff, a bit repetitive, including me.

Post by **bmcecosse** » Fri Feb 08, 2008 10:24 pm

If the engine is 948 there will be NO power loss. If it's 1098 then there will be slight power loss -but not significant if you are just trundling along. The 202 is a better flowing head - but needs skimming (60 thou) to use it on a 948 engine. Don't bother with 'additives' -really not necessary unless doing v high mileages and driving the car hard. I've never used any in 7 years - I don't do high miles but I do drive the car hard - and never had any problems. Worst that can happen is the exhaust valve gaps close up - so set them at 15 thou -and keep an eye on them, maybe every 3000 miles.

Post by **XDB** » Fri Feb 08, 2008 10:32 pm

thank you, at least I have a couple of heads if the worst happens, 3000 miles about 5 years motoring for me. an annual check can be done at oil change time.

Post by **bmcecosse** » Fri Feb 08, 2008 10:41 pm

You DEFINITELY don't need additives!

Post by **XDB** » Sun Feb 17, 2008 9:50 pm

as I said in a previous post, I am reading previous posts in the mechanical section. I have found one recommending changing a 948cc camshaft for a 1098cc one. I am taking my engine out, when its a bit warmer, and I have a spare camshaft. I was thinking of changing the oil pump. is it worth changing to the 1098cc camshaft as well, Your thoughts please.

Post by **bmcecosse** » Sun Feb 17, 2008 10:50 pm

Yes it is a better camshaft with extended valve period and higher lift. So if you have it and the engine is coming out anyway (although the cam CAN be changed in-situ ) then make the swap - especially if you also fit the 202 head after skimming it 60 thou - you will potentially have the same power as a 1098 engine (48 bhp) but of course at slightly higher revs.

Post by **XDB** » Sun Jun 01, 2008 10:05 pm

Should have listened, I fitted CAM 4810 head to my rebuilt 1098 engine, the performance is worse than my standard 948. I am going to fit 12g202 head and forget about unleaded conversions.

Post by **bmcecosse** » Sun Jun 01, 2008 10:11 pm

Wise move - but a 12g295 will be better, a 12g940 much better! Don't worry about the 'unleaded' caper - it's much overplayed.

Post by **XDB** » Sun Jun 01, 2008 10:15 pm

been trolling ebay and auto jumbles for either of those heads,nothing has come up yet.

Post by **youngun** » Sun Jun 01, 2008 10:29 pm

The 948 camshaft is utterly miserable accorinding to BMC, I have an MG Metro cam fitted on my 948 as per BMC's recommendations. Give me a year and ill tell you how it performs!