I'll shoot you some pics to your cell in a few (if it still works). They aren't much to look at. Stainless Marine Manifolds. Home made tails. Closed cooling of a pair of 350's. Johnson crank driven pumps. We tried Johnson Electric pumps almost got them to work. But they wouldn't pull water at idle. When underway they worked. Believe it or not the motors get about 300 hrs per season put on them. And the owner only changes the oil once per season if they need it or not. 0w50 Mobil 1. Like I said they are abused. After 900 hours the motor that has been overheated numerous times is starting to get low on oil pressure. It's coming apart this winter...

Many offset lifter builds. If so with what builds, heads etc

Pontiac style heads

I machine alot of lifter bores for lifter up grades to .904 and .937 rather then go to an .842 with bushing I would go to a .904 or .937.

I have seen about every lifter out there to size for lifter bores and to date ISKY .842 lifter are not .842 more like .8405 to .841 to put them in a .844 lifter bore and end up with .003 to .0035 oil clearance in not going make for a happy lifter. Same with Crower. There seems to be a lot of sizing issues that have never been addressed. The last set of bushed lifters had sizing issues and the Customer was not happy with their 1400.00 lifters.

Don't get me wrong ISKY makes a good lifter but having to buy 2 if not 3 sets to make up one set is not very cost effective.

Do a search on Yellow Bullet forum there is a lot threads about lifter sizing.

Comp Cams, ISKY and Crower and Jesel .841 lifters I have had to bush the lifter bores back and fit them to .0014 to .0019

Roller lifters like a controlled environment have oil clearance .003 to .0035 is not good.

Having alot of oil clearance with cost good HP because of extra unwanted bleed off.

Oil control is key to making HP
https://www.youtube.com/watch?v=SpfOKr3B3FA

There Does not seem to a standard when it comes to lifter sizing compared to OEM sizes

That video shows a good visual. https://www.youtube.com/watch?v=SpfOKr3B3FA

Jesel recommends .0018-.0022 clearance on there liffers

Thats a different clearance then I was told, So far everyone else seems to be right at .0014 to .0019

Interesting I have found that they work good at .0015

Egads with lifters being such a precision part why in the world so much fluctuations etc. Makes no sense. I realize the old days were much different and less hp builds but I've purchased many sets of hydraulic flat tappet lifters for both SBC and BBC and would never even give it a thought and they lasted for ever and the bores were always fine as well as the consistancy of the lifter size. Back then I used cranes. It just seems like as of recent (last 3-5 years) you always here about the latest best lifter only to find out it changes in 6 months and then there is another brand / part number, better oiling, better rollers, diameter consistancy, and on and on.

I'm just going to let my machine/speed shop purchase and check alignment and clearances. I mentioned in earlier post they still use cranes to date with great success and send a lot of builds out the door. They have a great shop with all the latest and greatest equipment and have been at it for many many years. I do understand oversize and even undersize but to have the inconsistencies in the same set is rediculous. I mean do some just install what fits best in what bore. Not a chance here.

Anyway Tks for the update. I appreciate and you just made up my mind and gonna call shop tomorrow. So what if I could purchase the same ones for 100 bucks or so cheaper. Leave it in their hands.

That's pretty good info

MT that was pretty amazing video. Many back yard hobbiest - builders would have no clue. To be honest I've never even seen anything like that.

I read .0020 for iron or brass and .0010 on aluminum and recommend to heat the block before use. Thought this came right off there site unless I misinterpreted it. So yes I'd say your right in there. Splitting hairs.