Alusil or Nikasil on 83SC ROW

Sumotang · Sumotang's Garage

I have done a search on Alusil and Nikasil and found heaps of info. But it appears that you have to have the engine apart to tell if you have Alusil or Nikasil cylinders.

My mechanic told me that since I have a 83SC ROW with a 9.8:1 CR the cylinders are Nikasil.

Is this correct???

I am looking at a top end rebuild soon and would like to know.

SpeedracerIndy · 05-12-2005, 05:27 PM

I have heard the same about the later RoW cars, but never a definitive answer. I would like to hear what the experts say. Too bad there isn't a way to tell without looking inside the cylinders.

Gunter · Gunter's Garage

It's a crap-shoot. You don't know until you open the engine. Only a few people have re-ringed Alusil P/C. Consider going to 98mm P/C along with 964 cams, if you find Alusil P/C in your engine.

Tom F2 · 05-12-2005, 06:37 PM

Spec book says all 930/10 motors (late RoW SC) had Nikasil/Mahles. That's what mine has.

diy83sc · 05-12-2005, 06:39 PM

I had an late 83 with the 3.2 case sans oil sump plate, K&S alusil setup.

Sumotang · Sumotang's Garage

diy83SC

Dumb question. How do you know if you have a 3.2 case?

Tom

If thats correct that would correspond to the 81 - 83 models with 9.8:1 CR. I maybe lucky.

SpeedracerIndy · 05-12-2005, 07:15 PM

Quote:

Originally posted by diy83sc
I had an late 83 with the 3.2 case sans oil sump plate, K&S alusil setup.

Was it a 930/10 (RoW 81-83) motor?

valenciacarrera · 05-12-2005, 07:45 PM

Sorry to go off into a tangent, but could one of you experts tell me if 3.2 ROWs are nikasil or alusil? Mine is 1985.

Thank you in advance.

diy83sc · 05-13-2005, 09:11 PM

The case *may* have been a 930/16; the car is gone now so I don't know for sure.

How you can tell it's a 3.2 case is that it does not have a sump plate, just a drain plug...

Wil Ferch · 05-14-2005, 07:20 AM

It seems all ROW 3.2's ( those w/o cats) ...are Nickasil

Look at your cylinder fins....is one with 10 fins and no vertical reinforcing bar....and the other 11 fins with vertical reinforcing bar.

Not definite...but 11 is usu Nikasil.....

Wil

Gunter · Gunter's Garage

Wil:
I was lucky to find Mahle Nikasil P/C on my 3.0 liter; but, they did not have the verical bar. I still think that it is 50/50 for what you have in any SC or Carrera.

Wil Ferch · 05-14-2005, 11:15 AM

Gunther...true enough...for cars meant for the states...

I'm quite certain ( 3.2's at least) that non cat Euro (ROW) cars were all Nikasil. Yes, there were cat Euro cars built to take advantage of a special tax break.

But you might be right for VERY late production 3.2's...if Alusils were around, they probably used them up.

Wil

john walker's workshop · 05-14-2005, 11:36 AM

niks have 11 fins, alusils have 10. niks have a dull, glass beaded look on the outside, alusils are shinier, even a bluish cast to the aluminum.

valenciacarrera · 05-14-2005, 04:42 PM

Thank you. That's what I was afraid of. I heard enough horror storries from BMW community with Nikasil.

SpeedracerIndy · 05-14-2005, 08:26 PM

Quote:

Originally posted by valenciacarrera
Thank you. That's what I was afraid of. I heard enough horror storries from BMW community with Nikasil.

From what I have read here, Nikasil is the one to have in a Porsche engine. Am I wrong?

dd74 · 05-14-2005, 08:48 PM

Quote:

Originally posted by SpeedracerIndy
From what I have read here, Nikasil is the one to have in a Porsche engine. Am I wrong?

Good question. I've never understood why Nikasil is better than Alusil. They're both a b!tch to pronounce, however.

Gunter · Gunter's Garage

Quote:

Originally posted by valenciacarrera
Thank you. That's what I was afraid of. I heard enough horror storries from BMW community with Nikasil.

You mean Alusil? Typo?

valenciacarrera · 05-15-2005, 08:11 AM

Let me clarify about BMW story. Sorry, it's kinda long.

A long time ago a Galaxy far far away........it involves 5-series BMW V8 such as 530i and 540i that was produced early 1990's. I guess back in 1980's BMW used Nikasil in their motor cycles. BMW car division heard of this application in motorcycle and decided to use it on the next version of their V8. The engine went thru the usual testing phase at Munich. They found the Nikasil to be quite beneficial to the new engine. So, they went ahead with North American launch in 1990. What they didn't count on was that unlike Euro gas, the sulfur content on US gas is much higher. The amount of sulfur is depend on brand of gas and geographical region. Apparently, sulfur from gas react with Nickel in Nikasil in these engines and eat away the cylinder wall. This caused the premature wears on the engine. When BMW NA finally realized the problem, they tried a quick and dirty solution by reprogramming the ECU to increase the heat on the engine. Their rational was that increased heat will delay the reaction between Nikasil and sulfur. But, this did not work at the end. BMW finally decided to bite the bullet and recall the engines. They ended up replacing Nikasil engines with Alusil engines and never looked back. (Luckly, Alusil was available on their 7-series at the time.) The recall was issued to the customers who complained so, there are still a lot of Nikasil engines out there. That is the reason these early 5-series with V8 has lower resell value that 6 cylinder models. I heard a similar situation with Jaguars, but I think, I bored you enough already. The ironic thing is, the new US gas regulation reduces sulfur content in gas, so Nikasil is no longer an issue in the near future.

SpeedracerIndy · 05-15-2005, 08:16 AM

Yes, i have read about the Nikasil problems in BMW engines here a few times. It seems though that it is isolated to BMW, and Porsche engines don't suffer from the same problems. I'm not sure why though. From everything I have read here, Nikasil is the one to have in a Porsche engine, but again, I'm not sure why.

valenciacarrera · 05-15-2005, 10:56 AM

Maybe porsche doesn't get affected because of cylinder wall lining. BMW didn't have them if I recall.