New question; L22s block and a87 peanut head?

Engine, Transmission and related drivetrain.
datzenmike
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Re: L22s block and a87 peanut head?

Post by datzenmike »

510rob wrote: 31 Jan 2021 01:06
datzenmike wrote: 30 Jan 2021 20:22Stroke in inches X RPM must be less than 4000 feet per minute.
Always useful to have a few heuristics, with the theory behind them. Thanks.
4,000 feet per minute is the magic number for piston speed. That's 45.45 MPH which doesn't seem that bad until you see that this is an up and down motion with massive acceleration and decelerations at about 60 degrees before and after TDC depending on rod stroke ratio. On an L20B with a 43mm stroke that's 116 times a second or .00862 second per revolution. With on line acceleration calculators I get well over 1,400 gee
acceleration/deceleration. L20B rods will weigh at least 500 gr. Pistons with rings and pins again at least 500gr. So a kilo (probably more) 2.2 pounds X 1,460 = 3,200 pounds of stretch acceleration 116 times a second on the rod bolts. Math is not my strong suit so you may get more.
"Nissan 'shit the bed' when they made these, plain and simple." McShagger510 on flattop SUs
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gumby510
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Re: L22s block and a87 peanut head?

Post by gumby510 »

datzenmike wrote: 07 Feb 2021 15:48 Generally a long rod allows the piston to remain near TDC slightly longer than a shorter rod. The longer time it is there, the more time the expanding gasses have to push and impart motion to it. Important at high RPMs. All other things equal a longer rod has less side loading on the piston as it approaches and leaves BDC so less vibration and friction. No, it makes very little difference, it's splitting hairs. Any rod stroke ratio over 1.5 is fine.
If sticking with the factory l18 length rods would you just do arp studs or new forged aftermarket rods.

Im asking because I just happened to find some new forged l18 88.5mm pistons for a screaming deal.
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71 PL510
92 rhd 180sx
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Re: L22s block and a87 peanut head?

Post by gumby510 »

Well, I bought a z20e out of 80 200sx. $300 for shipping wasnt to nice but what can you do when local isnt an option.

I ended up with some arias 87mm pistons with a 38mm pin height. Just purchased some z22 145.9mm rods.

I still might buy the 88.5mm pistons so I can have a 2.1L vs 2045cc but we will see after I actually have the engine in my garage to see if the 88.5 will fit safely. If the 88.5mm will fit safely ill throw the 87mm in my L18 that is currently in the car as my "backup" engine.

So with using the l20b front cover I have will the 200sx oil pan work? Its front sump which is what ill need for next winter when I do the jcb rack conversion.
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datzenmike
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Re: New question; L22s block and a87 peanut head?

Post by datzenmike »

Z20 oil pan won't work.

Z series engines are tilted to the left side of vertical about 8 degrees.

L series engines are tilted 12 degrees to the right of vertical, so a difference of 18 degrees.

A Z oil pan on an L engine would see the right bottom side the lowest point on the car.



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gumby510
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Re: New question; L22s block and a87 peanut head?

Post by gumby510 »

datzenmike wrote: 19 Feb 2021 18:39 Z20 oil pan won't work.

Z series engines are tilted to the left side of vertical about 8 degrees.

L series engines are tilted 12 degrees to the right of vertical, so a difference of 18 degrees.

A Z oil pan on an L engine would see the right bottom side the lowest point on the car.



Image
Excellent visual, thank you.

I was hoping this z20 was going to solve my needing a front sump pan for the jcb conversion. Guess not.
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datzenmike
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Re: New question; L22s block and a87 peanut head?

Post by datzenmike »

The L series was used in many cars and all used a different pan. All had the steering at the rear and a cross member at the front, so the lowest part of the sump was more to the middle front. I don't know why Nissan didn't use one design for all.
"Nissan 'shit the bed' when they made these, plain and simple." McShagger510 on flattop SUs
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