Hi. i have a 1100 with a 12G202 head. its was built by an unknown person at an undetermined time.

http://www.ausmini.com/forums/viewtopic.php?t=57037


recently i was informed the block is heavily decked. i was playing with the tune of the engine and while performing a compression test found the engine had just over 200PSi in each cylinder.

now initially i felt better that at least the compression was the same on each cylinder, as i had a feeling the head gasket may have gone or there may have been a crack somewhere. but this has now been proven fine.

my question is, the head is sitting hard on top of the water pump and the block has clearly been decked by a considerable amount due to the fact the engine number is no longer present and of course the fact the head is hitting on the water pump. does this present any problems? how much can you deck these blocks?

i plan on removing the head and possibly replacing it with an alloy one or a better version of the iron head, and was worried i may end up pulling it apart and be stuck with an engine i cant do anything with!

at the moment the engine does get a light ping every now and again and has to run high quality 98 octane fuels otherwise it really does ping its head off at any throttle. i have played timing games now each night for some weeks and this has no effect on the above. the pinging is not related to the timing in this case i am sure, it is strongly related to the compression.

should i just bin this engine, sell something, and get an 1275?

is it worth buying a recon exchange power unit as a whole?

or do you think it best to build your own?

i would love some feedback on this guys.

Thanks, Jason

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'66 BRG Morris Mini Deluxe 60HP ATW

First off, I would remove the head and grind some clearance on the water pump.
If the block has been decked heaps it may have funny pistons in (eg 68mm Hillman Imp) but this is no reason to bin it, if not using oil or blowing gaskets.

Measure the combustion chambers while the head is off, you can then get them enlarged if needed to reduce the C/R to whatever you want to use.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

someone spent a fair bit of money / time and effort on your motor.


If theres nothing wrong with it just drive it....

If it blows up a new block will cost you bugger all anyway. Why throw away something that someone spent money on.?

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I agree, sounds like a nice engine. Continue to run ultimate 98, and check the timing advance and plug type to eliminate the pinging.

Enjoy!

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Too many cars, and too little time.

If it does not ping keep driving it.
If it does ping or you need to remove the head then you should measure the compression ratio.

Can you machine up a gasket-shaped spacer? Or use two gaskets to reduce the CR?

you could try an octane booster additive in the fuel every time you fill up,this will eliminate the pinging,thats what i have to do to mine,and i agree with the rest of the lads,DRIVE IT....

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First you get the money,then you get the power,then you get the Mini.

Jason, keep in mind that un-leaded fuels with octane ratings over 95 loose their rating with time (1 to 4 weeks).

If it runs, get it sorted on the dyno. There is a good possibility that the carbie and dissy have not been set up correctly for your engine.

If you opt for a re-build, and IF you have a 1275 to start with, I'd go for the 1275 as the reco costs are similar.

I have played with the timing a little, retarded a degree or so and am using an octane booster now. i also tried a few different needles in the SU and think i have it about right for now.

thanks for all your imput guys. greatly appreciated.

Jason

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'66 BRG Morris Mini Deluxe 60HP ATW