Engine Theory, Build, Etc Discussion.

BlkCurrantKord

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LoL - Well umm...not really sure what to tell ya cuz I'm not sure what it is your asking. The stroke is how far the rod journal is extended from the main body of the crank. In our case its 97mm, in the case of H22's its 90mm.

Knife edging doesnt increase or decrease stroke. It narrows or "knife edges" the journals on the crank so that it cuts through the oil in the pan more efficiently w/ less drag.
 

BlkCurrantKord

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If I can get Drew or someone to come over I'll take some pics of this stuff to better explain it. Cuz I've bascially got an entire bottom end of an engine to work with.
 

xci.ed6

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LoL - Well umm...not really sure what to tell ya cuz I'm not sure what it is your asking. The stroke is how far the rod journal is extended from the main body of the crank. In our case its 97mm, in the case of H22's its 90mm.

Knife edging doesnt increase or decrease stroke. It narrows or "knife edges" the journals on the crank so that it cuts through the oil in the pan more efficiently w/ less drag.

The crankshaft should never touch the oil in the pan. There is a heavy oil mist in the crank case from oil coming past the main and rod bearings though.

It is done to the counter weights, not the journals.
 

xci.ed6

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If I can get Drew or someone to come over I'll take some pics of this stuff to better explain it. Cuz I've bascially got an entire bottom end of an engine to work with.

I've got a D16A6 disassembled on my bench...If I get time I may take some pictures, I have a load of stuff to sell on ebay anyway.
 

turboputz

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Well for basics, the rods are connected to the crank and as it spins it moves them up and down. The crank determines the stroke. The stroke is how far the distance is from when the piston is at its lowest position to its highest. To my knowledge the major modifications made to the crank are: knife- edging, micropolishing, and balancing. The goals of these I believe are to reduce rotational mass, reduce bearing wear, and ensure the crank is balanced so that it doesn't get a wobble at high rpms.

I do not know about mods to the crank that would increase stroke. That is most often done through the use of an aftermarket stroker crank. B16's are stroked to 1.8L 4G63's can be stroked to 2.3L, etc.
 
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BlkCurrantKord

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The crankshaft should never touch the oil in the pan. There is a heavy oil mist in the crank case from oil coming past the main and rod bearings though.

It is done to the counter weights, not the journals.


I know this, just trying to answer one too many questions at once.
 
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