Originally Posted by edvancedengines
Odd'
Carl,
I find the Drat Blocks seem to be machined much better with higher quality than the World stuff is. I have never seen anyone's line honing that is truly the same on each main journal, Dart is no exception. I always have to use several bearing sets to get clearances I want no matter if it is new from Dart or fresh for Reher Morrison or other shops.
Dart is using CNC Decking equipment. What is wrong with the decks? Most I am measuring are very close from one side's measurements to the opposite side's measurements, as close as .0002 . Not an error. That is three zeros.
I am willing to be educated though.
Ed
We have 6 Dart Little-M blocks in shop right now and the mains on the first 3 blocks are 2.640 after we clean and relube the bolts with CMD-3 and when we are done they are with in .0001 with no problems.
As far as the decks on the blocks I have bought Dart can not sweep off the deck and the rear of the deck as there is always a small step in ALL the Little-M's we have in the shop and on the deck about an inch from where the intake bolts on there is also a step in the decks. Dart can not machine the whole deck in one cut as they do about 3 different cuts and with the amount they are taking of the decks I am sure its hard to match mill to .0000
We probe out every block that goes through our shop and I know the probe does not lie as we have had some old Cup blocks in my CNC machine and between the decks and cylinder placement we have found those blocks well with in .0015 on both the Ford and Chevy blocks.
Ed I hope you not one of those guys that throws a boring bar on a block and bores the cylinders to where they are located as we are set up to BLUE PRINT BORE OUR BLOCKS. On the last 3 blocks we ran through our CNC machine 2 of them were with in .0025 from intake to exhaust and were with in .001 from front to rear. On one of the blocks we found the cylinders off .0065 on one side and -.0055 on the other side and thats from intake to exhaust and front to rear was with in .001 now thats .012 over all (correct). Thats why we buy all small bore blocks and blue print bore them to spec.
3 years ago I spent some time with Dick who runs the CNC shop for Dick Maskin and told him what I was finding when probing the blocks out and his reply was that we produce 150 blocks a week and we rough machine these blocks and its up to the engine builder to make sure that they are to BLUE PRINT and Dick also said that if any one wanted a truely blue printed block they could machine one for them but it would cost them.
Thats why I spent 124,00.00 dollars on a CNC machine to blue print machine all the blocks we send out the door and the ones we use in our engine shop.
Go over to the
http://speedtalk.com/forum/index.php...89d986a2c13b80 and ask if I know how to line hone as we have done blocks for quite a few of those guys over there and I have got calls from a few of them saying the sizing is right on the money.
Line honing is an art and not every one can line hone and have it come out right as we see this all the time and the Dart blocks we have seen right from Dart seem to be well with in .0001 but all seem to be under the low side.
We have shipped a lot of blocks over the last 8 years and so far no complaints on the work we produce and I have some of the best measuring equipment at both my CNC shop and engine shop.
Now on the Bowtie blocks we find the mains on those blocks in the middle to high side.
Back to the decks on the Dart blocks maybe they send me all the messed up ones as they know I can straighten them out when I am done LOL.