Thanks again for another good reply Mike!
To answer your question, I haven't built any Alusil engines but have built some Nikasil engines for Yamaha snowmobiles and motorcycles about 10 years ago when I used to ride.
My area of expertise now is heavy duty diesel engines which I work on basically every day. These diesels do run liners (sleeves), however they are a wet liner. The wet liner is directly in contact with the coolant and sealed to the block with o-rings.
My reasoning for the detailed post about Alusil was because you didn't mention in the thread or on your site anywhere that you guys machine alusil blocks and you don't list Mahle as one of the vendors that you use.
I am sure when it comes to sleeving BMW engines you guys are probably the most experienced shop I have heard of (trust me I searched after first reading the thread) and I trust that your workmanship is top notch.
As for the heat transfer comments of mine and your rebuttal questioning my experience and asking how many Alusil/Nikasil blocks I have sleeved, that is irrelevant. The heat transfer rates are basic metallurgy, it makes no difference how many engines you have done, Alusil conducts heat at 400% greater rate than cast iron period, end of story. I shouldn't have to tell you the benefits of a cooler running cylinder bore, since there are many. The main reason for hot rodders doing aluminium heads today and in the past besides reduced weight, has always been the ability to run at least a point higher compression on pump gas due to the increased heat transfer ability of the aluminium. This was especially important in days gone by when there was no knock control on cars.
My intentions are not to discredit VAC or take anything away from this engine build thread, I would just like to know that you guys are able and willing to do machining on Alusil blocks, I saw from the photos that you have a boring/honing machine that is more than capable of doing the job. If you are willing and able, we can talk about building me my stroker!
Now hurry up and get this thing on the DYNO, I wanna see what it puts down for power