I got this info off an Australian ZCar web. I just looked at the pin height

L24 piston has a pin height of 38.10

The LZ22S piston has a pin height of 35.

Given my extra stoke, I am guessing this piston is just about right on the pin height. What do you think?

Where can I find this?

ten charecters

According the information I've found, and your given setup this is what I get;

Bore: 87.5mm (Z22S + .5)

Stroke: 83mm (LD28)

Piston Dome/Dish: -9.33cc (Dished)

Head Gasket Height: 1.25mm (Stock?)

Head Gasket Bore: 88mm (Stock?)

Combustion Chamber Volume: 53.6cc (P90)

Piston/Deck Clearance: -1.02mm (below deck)

Compression Ratio = 7.5:1

Displacement = 2993cc (~3.0L)

This is assuming you are using a stock head gasket. If the stock head gasket compresses some (~1.125) you may get about 8.5:1 compression. This is also assuming that the Z22S pistons are actually 87.5mm diameter. A +1 Z22S piston is 88mm. So, I guess you have a +.5? A +1 would give you;

Compression Ratio = 8.57:1

Displacement = 3028cc (~3.0L)

To get more cmopression, you may want to use the N42 Head which will give you a 8.42:1 compression ratio. Again, this is all assuming the aboce calculation are correct.

The only combination I see to acheive 9.4:1 compression is;

Piston: KA24E +1 (90mm!!!)

Crank: LD28 (83mm)

Rods: L24 (133mm)

Piston/Deck: -1.37mm (below deck)

Head: N42, N47

Gasket: HKS 1mm Heigh x 91mm bore

ten charecters

google.com? :lick: I didn't find that one. I usually use this;

http://www.csgnetwork.com/compcalc.html

I was asking because I wanted to know the exact one he was using since I came up with different results.

No, a link to it was posted on this site a long time ago.

If you'll notice, it came from an Australian website (as he mentioned). Since there aren't too many of these L6 specific programs out there, IMO it's likely that it MAY be the one he was using. (we'll never know unless he answers your query)

I am using a Felpro H/G which gives 5.7cc's (stock is 7.1cc's), the F54 block is bored .060 (87.5mm), I am using a P90A head (53.6cc's), LD28 crank (+4mm) and 240 rods. I get 499.122cc's for each cylinder. 2995 cc's is what we get for total displacement. Once I get these LZ22S pistons I will know more about our compression ration.

I am using a Felpro H/G which gives 5.7cc's (stock is 7.1cc's), the F54 block is bored .060 (87.5mm), I am using a P90A head (53.6cc's), LD28 crank (+4mm) and 240 rods. I get 499.122cc's for each cylinder. 2995 cc's is what we get for total displacement. Once I get these LZ22S pistons I will know more about our compression ration.

Ah, ok. In that case, I'm getting 9.43:1

Bingo! That is what the Australian L6 page gives for the compression ratio. I am hoping this is correct! Nissan had 5 pistons but had to order 1 more. I hope they are from the same 'batch' and will balance OK. We had one set of V/6 pistons where one piston was 8 grams heavier then the others. Hard to get 8 grams out of a cast piston. We had to lighten the wrist pin to get the assembly to balance. Only time will tell. I get a bit anxious about this project. My wife tells me I have all of the time in the world. Who cares if it takes a year. It keeps me off the streets! (Off the golf course and rivers, too.)