I was told an engine i bought has a Z crank was a bit suss,ive pulled the sump off aanndd...........




I think it does....on the crank counterweights???? at each end of the lobe it has been chopped off,which i think
is what is ment by "if modoified they fit" Wadya recon??

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i can turn any hexagon into a perfect circle,pass me the multi-grips will you?

Ok. Crash course. All the counterweights will be ground down on a Z 24 crank, which will only fit into a L20 block. Same with a z22 Crank. Unless its has had RIDICULOUS amounts of work to the block. including line boring and lots of unnecessary money thrown at it for no apparent reason...
But the tell tale is that if its a Z24 crank, the stroke on the piston will be 96mm for a Z24 crank and something else for a Z22. So get your verniers out. And measure from the top of the deck to the LOWEST part of the piston. And then measure the same for the HIGHEST part when on compression stroke. And subtract the two.

Please post the outcome.

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Ongoing Project: 1972 Datsun 510 S13 SR20Det. http://ozdat.com/forum/viewtopic.php?f=33&t=17898
New Daily: D22 Navara (The new workhorse)
Retired 12/2016: MY98 Subaru Impreza RX
Previous Car: Restored Green 1972 Datsun 510, Hot L18

ok,i will tonight,thanks heaps,this block has had alot of work done,the cranks still in there and it seized up
its definatly been bbored a lonngg way out,oh and its a L16

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i can turn any hexagon into a perfect circle,pass me the multi-grips will you?

hang on....i dont have veniers or any spare cash..

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i can turn any hexagon into a perfect circle,pass me the multi-grips will you?

ok so ive discovered it is a Z crank its been put into a very hacked up L16 with 88ml pistons,im going to get a L18 bored out to put the bigger pistons in,what diffrence will a Z crank make? more power/less revs?? should i use an L20 crank in the l18block?? i have heaps of bits and peices and i wanna build a frankenstein..

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i can turn any hexagon into a perfect circle,pass me the multi-grips will you?

any spare cash = no frankenstein

most of the cost is in the machining not the parts aquiring and not many of us are skiled enough or have the equipment to do it ourselves.

but good luck anyway love a hot L series

What is the stroke? what is the main journal bearing size? What makes you believe it is a Z crank? Are you sure it isn't just a normal stroked crank as opposed to a "Z" Crank with extensive work done to the block?

A stroked crank will give you more torque, less revs.

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Ongoing Project: 1972 Datsun 510 S13 SR20Det. http://ozdat.com/forum/viewtopic.php?f=33&t=17898
New Daily: D22 Navara (The new workhorse)
Retired 12/2016: MY98 Subaru Impreza RX
Previous Car: Restored Green 1972 Datsun 510, Hot L18

Ive showed pictures to somebody else and ive been told its a Z,what is stroking a crank? im still learning,its all been pulled apart so i cant measure the stroke,wheres the main journal bearing?


As for no spare cash that was a few weeks ago,and this will be a slow build, 50-100 bucks a week type thing,ive got 4 L18 blocks 1 a87 and 3 w53s

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i can turn any hexagon into a perfect circle,pass me the multi-grips will you?

Ok, The main big silver bits that the counterbalance weights bolt onto in the MIDDLE of your crank. Ie. Lie it down and the ones in the centre with counterbalance weights either side, or the bits that the main bearing caps bolt to the center of your block when you put the crank in... are your main crank journals. What size are they? Measure with verniers or a ruler if you must and tell the measurement.

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Ongoing Project: 1972 Datsun 510 S13 SR20Det. http://ozdat.com/forum/viewtopic.php?f=33&t=17898
New Daily: D22 Navara (The new workhorse)
Retired 12/2016: MY98 Subaru Impreza RX
Previous Car: Restored Green 1972 Datsun 510, Hot L18

Just post up some pics of the crank.
Its easy to tell the difference between a L series crank and a z22/z24 crank.

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When the sign says "don't feed the bears", man you better not feed the bears.

ok,i will definatly do thisarves

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i can turn any hexagon into a perfect circle,pass me the multi-grips will you?

The pic in your other thread shows a "fully counterweighted" crank., whereas a Z24 isn't fully counterweighted (not sure about Z22).

The counterweights are machined down on their perimeter rather than how the ones in your pic appear to have been done. See shiny bits on the outside diameter of counterweights in the pics below, the 2nd pic shows one machined down and the other yet to be done. Also notice how each cylinder only has one counterweight on the crank.

If I had to guess, I'd say its an L20B crank with big diameter pistons fitted to an L16 block for the purposes of remaining legal for rallying. Using an L20B engine wasn't allowed, so the trick used to be massaging an L20B crank into the original block to get a big capacity engine that was still legal. The telling factor will be the main bearing diameter (although I guess that could have been machined down to fit the L16 block, rather than having the block line-bored to take the crank ??). Still a very interesting engine if that's the case.

To be 100% sure, you would need to measure the stroke as mentioned above.

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1970 ex Group A Rally P510
1971 P510
1972 180B SSS
1965 SP310 Fairlady
1966 SP311 Fairlady

Dave makes a good point.
The Z22 crank will "Just" fit into the L20 block without being shaved down - I would therefore assume it would still need to have been shaved for the L16 or L18 if used in that block. And it would cost a lot to do the main bearings/journals on the crank to fit into the L16 block. But i'm definitely interested in what It could be.

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Ongoing Project: 1972 Datsun 510 S13 SR20Det. http://ozdat.com/forum/viewtopic.php?f=33&t=17898
New Daily: D22 Navara (The new workhorse)
Retired 12/2016: MY98 Subaru Impreza RX
Previous Car: Restored Green 1972 Datsun 510, Hot L18

measure the stroke. a ruler will be close enough.
Crank could be std 1600 or L18 import from Z18.

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"R.I.P. Baz. 29 April 2022. Thank you for all your contributions to the Datsun community over the years. You will be missed." - OZDAT

to measure it ive gotta put everything back in.....

Aaand now im pretty sure its just an l20 crank the 1 on the left is a l20,the right 1 is the suspect.

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i can turn any hexagon into a perfect circle,pass me the multi-grips will you?