LZ23 long rod. What pistons

[DARIN 510]

So I'm in the process of build a lz23. And I have almost everything z22s block. Z22 crank. A87 open chamber and z20e 6 in rods. The problem I'm having is finding what piston to use. I've read that Jason grey shit already and that's a bunch contradicting info. Vg30 piston milled down 2 mm but rebello says it makes the piston too weak and tend to shatter? So he says custom pistons. But not trying to spend $600 on some pistons. Can anyone tell me anything. It would be a weight off my shoulders.

[datzenmike]

Cutting the tops will effectively raise the top ring closer to the combustion chamber and they will run hotter. I suppose trimming the tops would weaken the piston some but will... but for a street engine it would be fine. Rebello is more race/performance and so has to be cautious.

 

I would sell the 6" rods, bore to 89mm and get KA pistons for the Z22 or L20B rods. 2.3 (2288cc) motor with lots of compression.

[metalmonkey47]

Master-o-turbonics found that with an 86mm bore, forged Mahle pistons for I think a 4G62 or 4G63 (not sure) work perfectly with the Z20E rods. Might message him. Not sure exactly what he's got in my motor lol

[DARIN 510]

Master-o-turbonics found that with an 86mm bore, forged Mahle pistons for I think a 4G62 or 4G63 (not sure) work perfectly with the Z20E rods. Might message him. Not sure exactly what he's got in my motor lol

Could you find out. I want for sure answers. I see a lot of biased info on ratsun. Not going to spend money on some pistons that just maybe will work. If that is so on the 4g63 we need more info. What year of Mitsubishi motors. if they are different. How much. Specs of the piston.

[datzenmike]

Could you find out. I want for sure answers. I see a lot of biased info on ratsun. Not going to spend money on some pistons that just maybe will work. If that is so on the 4g63 we need more info. What year of Mitsubishi motors. if they are different. How much. Specs of the piston.

Then ask him yourself and get the info straight from him.... http://community.ratsun.net/user/5275-master-o-turbonics/  (sorry MM doesn't mean your info isn't straight, just why should you have to do it)

[DARIN 510]

Yah I got no response. So now what

[Stoffregen Motorsports]

In my experience building a long rod 2300 with a Z22 crank, a custom piston is required. JE or Wiseco are both available through Rebello.

[Xnke]

Yah I got no response. So now what

 

You start doing your own math and your own homework.

 

What's your deck height? And stroke length? Piston diameter? Pin height? Do you know how tall of a ring pack you need for your custom engine? What's the chamber volume of YOUR A87 head? Are you going to bother getting it ported? (probably not, since a 400$ set of pistons is just too much)

 

What is the end goal here? You can make more power on a stock bottom end L20B with a ported head and a properly sized camshaft, than you can on a big-displacement bottom end with a stock head and cam...

 

For what it's worth...you need a set of 87mm pistons with a 29mm compression height and a 21mm pin. Good luck, check some motorcycles.

[datzenmike]

You start doing your own math and your own homework.

For what it's worth...you need a set of 87mm pistons with a 29mm compression height and a 21mm pin. Good luck, check some motorcycles.

Well as discussed, VG30 pistons with 2.7mm milled from the top outer edge would work but this does not make a 2.3 at all. Doesn't even make it all the way to 2.2. Hell might as well just keep it a stock Z22 with an L head.

 

Using 1mm oversize VG30 pistons help get it to 2.236 liters.

 

 

Cutting the tops will effectively raise the top ring closer to the combustion chamber and they will run hotter. I suppose trimming the tops would weaken the piston some but will... but for a street engine it would be fine. Rebello is more race/performance and so has to be cautious.

 

I would sell the 6" rods, bore to 89mm and get KA pistons for the Z22 or L20B rods. 2.3 (2288cc) motor with lots of compression.

.

You can also use 89mm Z24 pistons and open chamber L head for 8.4 compression... 8.8 with closed chamber.

NOTE: The Z22/L20B rod small ends will need to be narrowed to properly fit into the Z24 piston

[EricJB]

If you plan on running cast pistons, your redline will be 6500, maybe 7000. Any more than that it might be short lived. Usually the skirts folding in or breaking.

 

I can assure you Z22/L20b rods will work just fine. I have used Cheap ass 89mm Silvolite 9115 std. pistons in my truck for 2 years. $167.00 from Summit. They are floating wrist pin style.

They have taken a horrible beating.  

 

Don't waste your time trying to achieve a rod ratio for a motor that cant spin. My .02 

 

 

[DARIN 510]

You start doing your own math and your own homework.

 

What's your deck height? And stroke length? Piston diameter? Pin height? Do you know how tall of a ring pack you need for your custom engine? What's the chamber volume of YOUR A87 head? Are you going to bother getting it ported? (probably not, since a 400$ set of pistons is just too much)

 

What is the end goal here? You can make more power on a stock bottom end L20B with a ported head and a properly sized camshaft, than you can on a big-displacement bottom end with a stock head and cam...

 

For what it's worth...you need a set of 87mm pistons with a 29mm compression height and a 21mm pin. Good luck, check some motorcycles.

Yep got those specs already. Thanks for telling me again.Going 89mm bore. Motorcycle pistons. Never heard of a 87mm or bigger in a bike. Heard about a possible chevy piston. Still checking into that. No not $400. It's $600 for pistons that's what Dave said. Not trying to be hella cheap just not trying blow money. You know that's why you got into datsuns

[datzenmike]

89mm bore on a Z22 crank will get you near 2.3 (2288). I'm building one with KA pistons and L20B rods. I honed the small ends to make them floating.

[EricJB]

Try going through this catalog for specs, then order from some place else for that application. 

 

https://www.uempistons.com/catalogs/silvolite_catalog.pdf

 

[DARIN 510]

Thanks Eric and that's a dope ass 521!

[heretic]

I'm running 89.35mm (3.518") in my 49' Harley, the newer twin cams run 98.42mm (3.875")

 

.....  Motorcycle pistons. Never heard of a 87mm or bigger in a bike...... 

[Stoffregen Motorsports]

Don't waste your time trying to achieve a rod ratio for a motor that cant spin. My .02 

 

 

I agree. I have never liked the long rod 2300. A long rod 2200 (89mm bore and Z20 crank) is much more fun to drive.

[Xnke]

Motorcycle pistons. Never heard of a 87mm or bigger in a bike. Heard about a possible chevy piston. Still checking into that. No not $400. It's $600 for pistons that's what Dave said. Not trying to be hella cheap just not trying blow money. You know that's why you got into datsuns

 

 

Japan-built strokers used Honda XL500 or FL500 pistons on L14 rods, or cheaper L24 rods and KA24 pistons. There are LOTS of motorcycle pistons out there in the range of 85 to 90mm, a lot of them are forged, and a lot of them use a 21mm pin. Most are high-compression designs, however.

 

Ross Racing Pistons will cut you a custom set for about 400$. Dave isn't the only source...he's reselling them and he'll make sure he makes his profit, just like any other reseller.

 

And no, I did not get into datsuns because they were cheap. I spend several thousand dollars a year in building datsun engines and transmissions for racing, and my 240Z is in my driveway because my dad had two and a half of them, and a little model car used to sit on his cabinet in the kitchen. Ever since I saw that model car, I wanted one of these, so I paid what I felt I needed to pay, and then I fixed what i felt I needed to fix.

 

Not all Datsuns are cheap...and to be honest, most datsuns AREN'T cheap.