alusil or nicasil

[markwemple]

Pulled my heads off and now I am trying to figure out what I have alusil or nicasil. For my 3.0 I know it could come with either but I don't see any marks indicating which. How can I tell.

[Alan Cottrill]

go get a magnet off of you refrigerator and see if it sticks to the cylinder wall. if it does it's nikasil if it don't it's alusil.

[markwemple]

I guess I am SOL. The magnet didn't stick.

[Rondinone]

I wouldn't cry yet. We in the "re-ring alusils" thread have copied a procedure for refinishing the cylinder wall at home for not much money. Read the thread and PM me if you have questions.

[Grady Clay]

Mark,
Today I got an e-mail from a Pelican about his cylinder leak test yesterday. This is a ‘72T that we built as a 2.8S with Nikasil 92 mm RSR P&Cs in 1974.

Here are yesterdays measurements:

#1 - 3.5 %
#6 - 2.0 %
#2 - 4.0 %
#4 - 2.0 %
#3 - 4.5 %
#5 - 4.0 %

Nikasils are amazing!

I expect the numbers will be all 2% or so when measured just off the track in a few weeks and not just street driving this past fall.

Nuff said!

BTW, the head nuts all took torque (but turned a little) and the case hasn’t been split since ’74.

Best,
Grady

[rick conrath]

You can have your Alusil cylinders re-coated with Nikasil. There is a "camp" that prefers the Alusil over the Nikasil. Check the threads.
Rick
'78 930

[Rondinone]

It's not a preference of alusil, it's a preference of money. Not everybody is keen to adding 3k to an engine rebuild.

But now that you mention it, why doesn't any current engine manufacturer use nikasil?

[Doug Zielke]

Originally posted by Rondinone
But now that you mention it, why doesn't any current engine manufacturer use nikasil?

Too expensive?
But many current m/c and p/w motors have Nikasil bores.
And what about light aircraft?

[blue72s]

My cylinders are Biral.. Can they too be coated with Nikasil?

[Superman]

I checked my oil this morning for the first time in several weeks. It was about a quart low. In about 3000 miles. Most of that quart leaked out between the right side chain housing and the cam housing. In other words, I'm not sure my engine is even burning the air-cooled "minimum" amount of oil. All evidence, including the butt dyno, suggest these ring are air tight. They were replaced at 182K miles, about 50K miles ago. The Alusil cylinders were simply reused. So to those who think their new Nikasils work better than my old Alusils, I say "Bring it on." I'll bet my leakdown numbers are similar to those posted above.

[markwemple]

Did you replace the rings because you had to or though it was a good idea?

[Tim Walsh]

Birals are very different. They're cast iron cylinders with Al. fins. They function exactly the same as Chevy cylinders. Nikasil and Alusil are Al with a special coating on them for wear.

[Rondinone]

That's great superman. So far, in the first 300 miles since my rebuild, the engine has burned 8 oz of oil. It had 115k miles, the rings were replaced because the valve guides were shot and I decided to rebuild the whole engine. Comp before teardown was between 150 and 155 for all cylinders.

Yeah, I know they're junk. Send me your old ones.

[blue72s]

Originally posted by l33t9eek
Birals are very different. They're cast iron cylinders with Al. fins.

Yes but what I asked is, can the cast iron walls be lined with Nikasil? (which is only a thin lining)

[Tim Walsh]

AHH.. that I don't know I guess the real question is how thin can you make the Al cylinders before you run into problems and then how thick is the Al exterior of the Biral cylinders.

I'm not sure why you want to coat the iron part of the cylinder since it makes a good wear surface.

Just some musings by an amatuer

[fly944]

Just read the other day that the Carrera Gt is using Nikasil Cylinders in the V10. Not sure of the exact specifics.

[cnavarro]

You can nikasil cast iron. Done it before for rare or NLA cylinders for vintage guys. Reduces friction (= free horsepower) and gives you a much better wear surface. Nascar guys use nikasil on their iron blocks for that reason.

Charles Navarro
LN Engineering
http://www.LNengineering.com
Aircooled Precision Performance

[blue72s]

I'm pleased to hear that.

The disadvantage of the Mahle-Nikasil ones is that, due to lack of steel, they have different expanding properties hence the need of dreaded dilavar studs to match. So "modified" Mahle-Birals, IMHO, would be a better solution as steel studs can still be used on them. Of course this type of mod can only be done on 2.4 or lower.

Right?

BTW, how thick is the cast iron wall of the Mahle-Biral? And how thick of nikasil lining would be rquired? (what was the lining thickness of the 2.7?)

The 2.2 & 2.4 Mahle replacements of today which are nikasil, are they of the exact same construction as the original 2.7?
Sorry for so many questions..
tahnks

[cnavarro]

The nikasil plating can be as little at .004" on diameter or in excess of .015" on diameter. For example, i've taken a stock bore 356 cylinder that was wiped out from a grenaded piston and have been able to overbore and replate to factory size, better than new.

Nickies cylinders in bore sizes from 84-86+ for the 2.2/2.4 and 89-92+ are fully finned and have provisions for oe sealing rings. Nickies in bore sizes 95-98+ are also fully finned, based on 3.0 KS alusils / 3.2 Mahles, not the half-finned turbo cylinders and do not use the sealing ring, per the design on the 3.2 mahle. Rather there is a taper on the sealing surface that causes a gradient in clamping loads, thus forming a carbon seal at breaking. Custom piston combinations with Nickies will be courtesy of Pelican Parts and will be available in kit form through the rebuild wizard hopefully sometime in the near future. Call Eugene for more details.

For those who don't know what we're talking about:

Fin shot of mahle vs. Nickies


Photos of a 92mm Nickies cylinder for 2.8 911:

http://www.lnengineering.com/gallery/Porsche%20911%202.2%202.4%202.7%202.8%20Nickies/Final%20Production%20Demo/index.html

Charles Navarro
LN Engineering
http://www.LNengineering.com
Aircooled Precision Performance

[markwemple]

How much does this run? ($)