i just pulled off my head (well basically tim did it) and we've neatly placed things in marked boxes, well bottles that are unmarked

anyway my mate timmy ( fitter and turner ) whipped out a set of micrometers and measured the bores the proffesh way

anyway we managed to find that they were .02-.03 out from the 70.61mm bore that my mini book suplied me with. basically they've been worn .02-.03mm depending on the angle inside the bore (ie east west, north south) and also the specific bore. we only measured 2 bores but they came up consistent. There's a very small lip on the top, but i can only feel it with the finger, u can't see it with ur eye's.

After all that jibber jabber, do we need to bore the block out? is it worth it? is the amount of wear alot for each bore? he just finished working the crap out of his 265 and it was .010" worn, and it needed a rebuild. we worked it out and .010" is .25mm and mine's worn .03 max.

Also we were able to see downward swirl marks which we think might be a result of honing. Is this factory? Or is this the result of being honed?

and another also, where do i find the markiungs on the head for the specific head type? i was able to find a marking on the top of the block "12HD24 134135" obviously that's for the block, but does that mean anything to u chaps?


ok im down for some answers. hook me up

so u got urself a 1275, good work

Rohan

_________________
1964 MORRIS 850 - POST ZOMBIE APOCALYPSE CAFE RACER INSPIRED.

https://spotify.link/D0P4KtIP2yb

1098 +0.40
266 Kent Cam
GR Flat top pistons
HS6
1.3:1 Roller tip rockers
Stupid high CR

.03mm is nothing. Just a bit over a thou. (hey I'm a fitter & turner too...).
Does it rattle? Use oil? No? Don't worry about it yet.

Numbers on the head of a 1275 are in the middle on top, under rocker gear. Scrape the sludge off, you'll see it..

It'll be 12G940 I bet, unless it's a `smog' head (with air injection ports) which are 12G1316.

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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.

so basically 850pv has got himself a 1275 ready to go into the car for under$700?!?! thats not half bad at all!!

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play 3d car games for free

Wack it in the car and see how she goes. Hell, you shoulda done that when ya first got home, having a flip front and all!

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Just rig some gravity feed fuel (or siphon from a jerry can...!), hook up a battery, and fire it up on the floor!
Oops- better check it's got oil in it first..

_________________
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.

I'm sure they would know if it had oil or not, as there would of been a nice puddle in the back of tims subaru!

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we dont know if it makes noises or anything, i just bought it silly

but while i have it apart should i do the good bits and bore it out 20 thou or so, put nice new pistons and rings in. I have a gasket set ( for free, thanks to miniimports ) and what about porting the head, i had a look at it, its a 12G940 but it was missing the 0 it read '12G94' then right next to that was a hole for the oilways or something, no room for the 0.

what about a cam etc.
coz if i just drop it in. i have all round drums
surely that's not cool.

but yer, the engine seemed pretty schmick. timmy sussed it out and couldnt complain about anything. he said himself it could be dropped in.

tell me what u think fellas

personally....id do some work on the head and leave the rest the way it is....and get some honda discs and stick it in ASAP!

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play 3d car games for free

who would want to do that for a living....

oh hang on....did I say that?

how crazy do ya wanna go with the 1275???

I mean - a little bit (1275cc with extractors)

or a lot (bored and stroked to 1600cc with the works)

1600cc!!! And I thought i was going stupid with my 1380!!!!



I'd basically concentrate on upgrading these things....
-Air filter
-Inlet manifold/carby
-exhaust/extractors
-electronic dizzy
-cam
-head work

Work on SMOOTH air flow

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[NATHAN] -- Sold everything mini related and am back in big beautiful BMWs

DISCS!? pft stuff that!

i got a 1275, a little bit warmish! it pulled up ok from 150kph! with DRUMS!

done on a track of course!

wouldnt be silly enuf to drive like that on the road!


Rohan

_________________
1964 MORRIS 850 - POST ZOMBIE APOCALYPSE CAFE RACER INSPIRED.

https://spotify.link/D0P4KtIP2yb

1098 +0.40
266 Kent Cam
GR Flat top pistons
HS6
1.3:1 Roller tip rockers
Stupid high CR

i have goals of beating my mate's cars.
1 of them is probably a win just with the stock 1275.
the other i MAY be able to beat him if i run something like 10psi through it with a worked 1310cc, with a nice cam, ported head, balanced bottom end (for revability), extractors, and some PHAT tread!


the other mates are either 2 fast or set up for rally.


all of that would be nice. BUT i do want to supercharge it because these days 1275's in mini's are reasonably standard (anyone that's spent enuff cash on their mini's engine will have one) and supercharging is far from standard.

if i can beat that second mate, i'll be keeping up with 5L VN's.
i can just imagine, some skinhead playing his doof doof rolls up and takes off as fast as possible simply for the dare-o factor and i catch him in style..

one word. RESTEPCA

guys like that back off when they see ya catchin em - they say they won, but wont race ya at the next set of lights

_________________
[NATHAN] -- Sold everything mini related and am back in big beautiful BMWs