Interesting Video of boring out cylinders

[mikedsilva]

I didn't know this was possible.. just happened across this video of a shop in the UK that bore out the 95mm cylinders to insert a steel liner...

[brighton911]

Thanks for posting Mike. P content starts at 10:52 although the first part is also interesting.

[stownsen914]

I've heard of doing this. I hear some builders prefer the iron or steel liners for high boost turbo applications.

[Neil Harvey]

Have never understood why though. Why add material that increases ring friction over the original liner material, when the "original" type if liner material is available for repair work.

[75 911s]

Don't they do this on the Alusil cylinders too?

[Henry Schmidt]

Originally Posted by Neil Harvey

Have never understood why though. Why add material that increases ring friction over the original liner material, when the "original" type if liner material is available for repair work.

Unique bores [95mm in a 2.0 case, or 101.5 in a 3.0 case] and increased cylinder pressures make these modified cylinders an interesting option. We've made quite a few cylinders over the years and our standard procedure is to Nikasil the cast iron liner, something we learned from the NASCAR builders.
Is this a state-of- the-art option? maybe not but after all, we're working with less than revolutionary design parameters.

These are JB Racing's version of a cast iron [Biral] cylinder we're using on a 2.0 vintage race engine going in a 914-6 GT were building in house.