Never said anything bad about the Darts main lines as we always find them under low side appox. .0005 and most of my customers want them in the middle to high side.
We had a World block in the shop to plate hone the cyliders and what a peice of shyt compared to a Dart, Worlds main line was just a very coarse line bored finish and the lifter bore finish was ugly looking.
On the 3 blocks we are machining the lifter bores are .0005 under the low side of the the GM spec and we have always had to hone .0002 to .0005 out to get them to spec. and I am sure the next three will be the same.
We did get a block from Dart 2 months ago where the lifter bores had .0008 taper and one bore was totally messed up and Dart paid for a set of severe duty Crower lifter .875 lifter and we machined the lifter bores to .8755 for the custmer for 150.00 and it was a win win situation for everybody.
When we had the deal on the Workd blocks it was costing us money as the last block we got was filled with epoxy up to the freeze plug holes and the customer didn't want it and they would not take it back so we sold it for 1300 dollars our cost to rid of it.