Newbie trying to upgrade my engine ?s

[62Countryman]

My Austin 7 Countryman estate (January 1962) has the original 850cc engine and I want to upgrade to a bigger engine if possible. A friend of mine is going to give me a 1000cc engine block which will come with flat top pistons, etcetera. I can purchase a used 12G295 head for the project. The cost of the head is $100.00 plus shipping. The seller guarantees that the head is not cracked. Is $100.00 too much for a used head? I need to check if the head has been skimmed. I have read on this forum that the thickness of the head should be 2.75" (is this correct?). In addition, the seller deals in triumphs, midgets, sprites, MGs but not Minis. Excuse my ignorance, but are all 12G295 heads the same not mater what A-series engine they were used on? I did not see double valve springs due to the picture angle. Will I be able to use the head on a 1000cc block? I also read on this forum that a 1000cc block will bolt onto my transmission case without any problems? I have attached pictures of the head. The part #s located on the head are: 433 MOWOG 12G295 3 28F.

Cheers

[Tim]

$100 sounds pretty good to me, assuming its not cracked. I reckon it does have dual springs, you can see what looks like the inner ones in some places. It should bolt straight on to a 998, but you will probably need to have it planed to get the compression ratio high enough (unless it has already been done). The 998 should bolt on to your existing gearbox but you may need to faff around with minor bits and pieces with the clutch end housing. From memory there are some dowels that are different. All 295 heads are essentially the same. It should make a decent little unit. I ran an 1100 with a 295 head for a few years and it was really good.

Tim

[LDR209H]

I was going to suggest building a 1098,the 12g295 would go nicely with it. You'd end up with an MG1100/1098 Midget engine,about 55 bhp and decent torque which would be useful in a traveller. Wasn't sure if the gearbox internals would take it if it was an early 850 magic wand box.

[Frogeye61]

The 1100 has quite a long stroke and I don't think it fits in the 850 box. I remember the bible saying something about that complete with pictures of grinding the case to make clearance.

That head does look skimmed, at least one time. Assuming 10 thou skim, on the 998 with flattops, CR around 8.6 is expected. A 30 thou skim should bring CR up to around 9.0:1

Yes a standard head is 2.75", so you want a thickness of around 2.72". That would give a chamber size of around 26.1cc (standard 12G295 is 28.3cc.)

[Tim]

If you wanted to convert the 998 to 1100, it only needs an 1100 crank and pistons. Then the best choice would be to fit a 4 synchro remote change style transmission with a pudding stirrer gear lever, as fitted to vans and Mokes. The gearstick comes out in the same location as the 850 but you gain a stronger gearbox with synchromesh on 1st gear.

Tim

[62Countryman]

Good news on the head. I had the seller measure the thickness of the head and it is 2.75" thick.