To sleeve or not to sleeve
#19
Three Wheelin'
Alusil is not a plated surface. The 944 block is alusil, an aluminum/silicon matrix with the aluminum in the cylinder walls removed to expose the harder silicon, nothing is ever added. You can nikasil it over but this is not cost effective in his situation. Neither is a deck plate at 340 hp. Please give advice on things you have experience with.
#21
Burning Brakes
Join Date: Jul 2004
Location: Kent, UK
Posts: 1,096
Likes: 0
Received 0 Likes
on
0 Posts
You need somebody with the correct equipment to hone Alusil, like said above when it is honed it brings the silicon to the surface and gives it the correct surface. If you use a standard hone tool you will do more damage than good. Find somebody who has done a lot of machining on either BMW V8's or Jaguar V8's both of these are Alusil bores. There used to be major problems with Alusil before they reduced sulphur in gasoline now there is no problem and it is a very durable material.
#22
Originally Posted by mark944turbo
Alusil is not a plated surface. The 944 block is alusil, an aluminum/silicon matrix with the aluminum in the cylinder walls removed to expose the harder silicon, nothing is ever added. You can nikasil it over but this is not cost effective in his situation. Neither is a deck plate at 340 hp. Please give advice on things you have experience with.
Nikasil is an electro applied coating and it suffered in the US from sulfur rich gas causing corrosion problems. Alusil liners were one of the solutions offered by BMW to remedy their problems with Nikasil & high sulfur gas corrosion, (Alusil being corrosion proof).