with the original low compression slugs and a ported 2.3 head that has not been shaved? Does the compression go up which i assume it does but does anyone know by how much? Please see my subject "2.5eta with 2.3head want to turbo" posted on 17/3/04. No one has responded to previous posts on this topic probably because it's a FAQ but hey, this is a turbo beemer forum so.... anyway I've been checkin it all out for a few months from Downunder in Byron Bay. I have an E30 with huge plans. It started out as an M323i with a tired 2.3(over 500,000 klms!!)that lived til the 2.7 transplant 6mths ago and used the original 2.3 head but had it heavily ported and the cam reground. It goes hard and i drive it hard with regular visits to redline searching in vane for more power but after 5500rpm it really is squeezing blood out of a stone. Anyway hope someone can read my other post and get back to me. thanks. Also can someone tell how to post pics. Have lots.