Nikasil Plating AA Biral Cylinders

[dennisO]

Hi All,

I was looking at the AA 2.4L 86mm low compression JE pistons and Biral Cylinder kits. Assuming this is a good idea and beneficial, I was thinking of getting the AA Biral cylinders Nikasil plated, but not sure of the procedure. Does the new cylinder bore need to honed to account for the Nikasil plating thickness or is the plating thickness thin enough that it doesn't matter? I researched this forum, but could not find any information.

Originally I wanted to use the original 2.4L Porsche cylinders, but I can only get them safely bored to 85mm.

Thoughts welcome.

[E Sully]

You could contact LN Engineering https://lnengineering.com/ and ask. I think the plating was designed for applying to aluminum. Even if it could be done I think the main benefit of heat transfer would be lost.
If you want Nikasil, I would look to buy actual 86mm Nikasil cylinders. LN Engineering offers them. A bit more low budget but I don't know the quality is QSC. https://www.qscusa.com/products/porsche-911-86mm-aluminum-nikasil-coated-cylinders-pistons-set
Henry Schmidt used to sell them, but I think quality can vary.
https://forums.pelicanparts.com/porsche-911-technical-forum/312904-qsc-cylinders-anybody-ever-use-them.html

[stownsen914]

I've heard at least one builder here mention nikasil plating biral. Wear resistance is one reason to do it.

[Henry Schmidt]

We do it all the time. I learned the technique by following NASCAR engine builders who have been coating their cast iron blocks for decades.
I rarely run a Biral cylinder sans Nikasil coating.
The benefits are fiction reduction, precise sizing, variable RA factors, better ring options and incredibly durable.
With the AA 86mm cylinders that we've seen, they tend to be a few thousandths over bore (30-40 thou ring gaps on new cylinders) so the Nikasil coating can bring the cylinders back into spec.
It's also a cool way to save a Concours build. New Mahle cylinders are Aluminum so the look is different. Many times the original pistons are still in spec so reusing then in a new bore is cost effective. The key is to get the correct rings.
Keep in mind the Biral cylinders have less expansion so choosing the correct piston material is critical. 4032 (vs 1826) is a better choice. Check with AA to see what material JE is supplying for their application.