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Discussion Starter #1
Im having trouble finding for the past 2 weeks anything
on rod stroke ratios or engine block height for the 105
2 liter, also piston compression height can anyone help?

crank centre to deck height for block dimension.
 

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I don't know the answer to your exact question. But the normal way to establish which size a Nord engine is, by measure how much the block end over the water pump, 0 mm = 1300, 25 mm (1") = 1600, 40 mm (1,5") = 1750 or 2000. Bore of the 1750 is 80 mm, and the 2000 84 mm, stoke both 88,5 mm. Compresion for 2000 engine is 9,0:1 (Euro spec).
I'll take a tape measure to my 1750 engine and give you aprox measurement of block and engine high later to-day.
Erik
 

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I've now taken the measurements of the engine of my 1750 (99% sure they are the same as 2000). High of the block circa 32 cm 12,6" and the engine (sump to valve cover RH side) circa 55 cm 21,65".
Mind you, in Alfas the engine is slightly canted to the left.
Erik
 

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Discussion Starter #5
Thank you for your help Erik

Ive marked in bright green what I mean which is measuring
from the crank centre to the top of the block.
regards, Dave
 

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If I remember correctly engine block height is 235mm, rod ratio is 1.78
 

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Discussion Starter #7
Thank you, its quite a tall block any piston size for compression height?

Rod stroke ratio is very good, it seems to help drive-ability when tuned close to 200hp.
 

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Varius Alfa parts supplies offer pistons with higher compression that not get hit by the valves with suitable cams.
Anyway, don't expect much driva-ability on public roads from an 200 hp Alfa Nord engine, it will be better suited for tracts.
Erik
 

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Discussion Starter #9 (Edited)
Im thinking of de-stroking to 87.5 mm (not much I know) re-hardening maybe just maybe some prepped Nissan conrods with custom cast hisil pistons. A closed deck plate tig welded at the top with some alloy C shaped lengths tig welded from base to deck on the insides of the block and drilled to take the studs and lastly a cheap Steel 12mm plate laser cut as a main caps ladder brace. Will all up be cheaper than a mono-block for strength using stock sleeves.

Nissan ka24 conrods
Length: 165mm
Piston End Thickness: 25.4mm
Big End Thickness: 26.8mm
Piston End bore: 21mm
Big end bore: 53 mm

-------Versus------

Alfa stock 2liter conrods
Length: 156.972mm (-8.028mm)
Piston End Thickness: ??mm
Big End Thickness: ??mm
Piston End bore: 22mm (+1mm)
Big end bore: 53.7mm

Can someone tell me the alfa conrod info marked as ??mm
Would it be best to machine the crankpins as stated? the rods are free I have piles of them.

Erik could you confirm the block height is 235mm on yours?
 

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Discussion Starter #14
can anyone help with the stock alfa rod info below?
Piston End Thickness: ??mm
Big End Thickness: ??mm
 
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