Is any of that an issue?

Is there enough metal in the block for both operations?


895cc with a better bore/stroke ratio sounds interesting.

Looking at some specs, i notice that there's a 0.065 inch difference between 850 and 998.

Cush there is no problem with boring, back in the 60s I used to overbore 850s and stick a new 1098 crank, rods and pistons in em.

The major mod was to the 850 centre main cap and block, to allow the 1098 crank to fit (its bearings are narrower). Won't affect you with an 850 crank.

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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.

Make an offer less than you would have to pay from Minispares with postage at a price you would be happy to pay as a 'fair' price.

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

Ohh. that's exciting...

SO what's the deal with overbore sizes..

SP64 Specs tell us that 998 is 2.543 in. does that mean the bore is 0.2543 and the piston is actually marginal smaller or is it the other way around?

That's a decent option, thanks.

I'll keep that in mind

2.543" is the actual bore size. Piston is a couple of thou less.
But best to not bore it until pistons are available to hand...

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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.

Whilst i think i know the answer..

I've got a good 998 block here with (surprise surprise) 998 std pistons, I could just use those, yeah?

The bores look look fine and i trust the previous owners opinion that all the block needs would be a re-ring (and i know you don't believe in that. )

I trust his opinion, because the PO was 50% of the duo that killed the mini 1000 series way back when...

don't use old pistons - new ones are too cheap

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did I tell you that I won a trophy?

even 998 stockies?

Yeh you need new standard stockies

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

Are 998 stockies actually available new?

Edit... yep.. 170 from the Kraft

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

Cush, If you want .020" and .040" oversized 850 pistons and rings then try your nearest Autopro shop.
The bloke I deal with at autopro in gawler can get a new set of pistons and rings for around $200
If you are building a stock eng then JP pistons also sell 850 pistons.
If you want 998 pistons Autopro can get them as well. There are some pistons available that have a pressed in gudeon pin instead of those nasty circlips and floating pins. The rod needs to be reamed out about .003" . The pistons have a cutaway skirt where the gudeon pin is but only have 3 rings.

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Research is the difference between speculation and investment. Anyone who copys some one else will always be second
www.minisprintgt.com

Don't forget 850s here had that `clamp bolt' little end in the rod. You would need to grind a notch in the gudgeon pins to fit 998 pistons (IMO not a great idea) or fit 998/1098 rods. Same length etc and fit fine.

_________________
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.