AHH! 280ZX Turbo piston problems. Help?

[jmurphz33]

First of all, I'm a new user---but I've been browsing the forums here for quite a while, and I like what I see. Seems like most of the guys here know what they're talking about, and it's encouraging, especially since I'll probably have a lot of tech questions down the road.

 

Anyways, onto my issue.

I bought my 1978 280Z last fall, and have until now been making it as close to out-of-factory driving condition---- now I'm ready to take the plunge and go for the L28ET swap.

I already have my F54 block, cleaned and ready to be honed, P90A head w/ some porting and a 3-angle valve grind job, crank polished, and rods ready to go. I'm having MAJOR trouble finding a good set of pistons, however. I'm looking for forged, none of this cast garbage---don't want them to shatter if detonation occurs (high boost setting will probably be about 15? ).

So, any help, or a link to a known good distributor would be AWESOME.

Thanks for the help.

...oh, and also--- anybody know if the bottom end in an 83 ZXT comes from factory with forgings?

[EZ-E]

If you do a search or go to the Vendors forum you will find many that have what your looking for.

 

Please support our Z guys, they do us a lot of justice in the quality parts they bring.

 

Some that come to mind straight away are

 

Ross at Modern Motorsports

Dave at Arizona Zcar

 

There are many more that commit to all sorts of services for our cars. Just doing a search on google will bring many more.

 

Good luck in what you are doing. Enjoy the site, it is the best techinical site there is with no misinformation and more then enough in the archives to keep you reading for ages.

[AnTmanS130T]

Detonation will kill forged pistons or cast aluminum ones... Yes I understand it will take a little more but that's a little more money. As far as the motor goes.. the crank and rods are forged from factory. The stock pistons can easily handle 15 psi without any detonation. Goodluck

[cygnusx1]

Yup, the stock pistons handle 15psi with even occasional light detonation in my experience. BUT, you have the right idea, get strong pistons and head gasket and ARP bolts now while you have it apart.

 

Good Luck!

[Shadytrixta1]

Detonation will kill forged pistons or cast aluminum ones... Yes I understand it will take a little more but that's a little more money. As far as the motor goes.. the crank and rods are forged from factory. The stock pistons can easily handle 15 psi without any detonation. Goodluck

 

Haha mine held 20psi from a Z31 turbo.Ran awesome, but couldn't handle 9psi from my T3/T04E

[Alex_V]

I thought the z31 turbo was the same as the L28ET's just with watercooling?

 

~Alex

[Doug71zt]

For the original poster - there is another thread recently about forged pistons - search PeteW and you should find it. Personally, I would stick with stock units if you are limiting yourself to 15 psi. If you think that you will run more boost in the future, by all means do the forged units now. I bought a set from Ross, but JE, Wiseco, and most other major makers will build pistons for the L28. Custom pistons from Wiseco run around 100 a hole, they will make anything that you spec. My Ross pistons were purchased in a Hybrid Z group buy a couple years ago, they just haven't made it inside an engine yet. I´m still running my JY stockers.

 

 

Haha mine held 20psi from a Z31 turbo.Ran awesome, but couldn't handle 9psi from my T3/T04E

 

BS

 

The turbo had nothing to do with the piston failure unless it fed them a bunch of compressor wheel bits down the intake.

 

Probably had something to do with detonation.

 

I'm running the largest trim (60) T04E compressor wheel, have been for quite a while, on stock pistons. Up to 23 psi at the track, with a number of trips off the end of the boost gauge when I had WG problems. Best guess between 300-400 passes. I think that I may have pinched a ring land a couple years ago running too much advance at 14psi. I had a bad leak-down number on one cylinder, which strangely fixed itself within 2500 miles. As you can see by my sig, I'm on the ragged edge of what I would expect them to handle.

 

They are a high quality stock cast piston, but keeping your foot in it when it is knocking will kill them quick.

 

 

Doug

[jmurphz33]

Alright nice. Thanks for the help guys!

I'm not totally sure if I'll never crank the boost up past 15, but I'll be tempted to. I might as well go forgings, I want this motor to be strong. Thanks again!

[randy 77zt]

i have spare motor on stand with 80,000+ mile running 15psi boost with stock 81zxt ecm and turbo.if you dont detonate it it will last without forged pistons.motor hit 20 psi a few times.finally blew the head gaskit.

[Cody 82 ZXT]

Alright nice. Thanks for the help guys!

I'm not totally sure if I'll never crank the boost up past 15, but I'll be tempted to. I might as well go forgings, I want this motor to be strong. Thanks again!

 

A forged piston is the way to go if you can.

 

Having said that theres nothing wrong with the cast piston if other things are kept in check. I've run over 20 psi a couple of times and had no issues.