Yellow Bullet Forums banner

81 - 100 of 111 Posts

Registered
Joined
14,638 Posts
I always used dial calipers when I was planing wood to size. My brother thought it was funny. Wood grows with humidity, and shrinks with lack of it.

When you cut wood to length there is usually a little fuzz on the bottom pf the cut. It's maybe 1/32 of an inch. So.....cut the fuzz off. No carpenter I've ever known ever bothers to measure anything that precisely. Cut it 1/16 big and cut the fuzz off until it fits.
My framing was always to the 16th and then one side of the line or the other. With a Skill saw. Uses to drive the rest of the guys nuts.
 

Registered
Joined
5,575 Posts
My Dad was a Tool & Die Maker, was first employed in the aircraft/aerospace industry in Southern California back in the early 1940's. I too have been around machine shops for over 60 years. Therefore I stand by my statement concerning the correct/popular way of stating measurements. In my opinion, when you express a measurement in terms of .xxx" + .xxxx" there exists the possibility of mis-communication, whereas stating this dimension as .xxxx" reduces the possibility of communication mistakes. In this example, .0027" states the exact measurement, no + or - which may be miscalculated.

I have a friend who owns a machine shop in the Houston, TX area doing work for NASA and others. I called him just to get his opinion on the matter and he agrees that .0027" would be stated as twenty-seven ten thousandths in his world. He also made some sort of derogatory statement about automotive machinists being glorified blacksmiths . . . . . . . .
Yep, and tapered pushrods are superior..............馃槀
 

Long Live The King
Joined
100,859 Posts
My framing was always to the 16th and then one side of the line or the other. With a Skill saw. Uses to drive the rest of the guys nuts.
boy does that sound familiar ... lol
 

Registered
Joined
3,603 Posts
Right, Motorsports are competitions of complete motor vehicles, drivers and maybe crew.

Includes Engines, drive lines, chassis, body, tires, humans etc.

HAPPY MOTORING means happy traveling, not happy Engine-ing.

ESSO isn't just referring to the Engine obviously.

SEE PRESIDENT TRUMP BELOW!!

GO PRESIDENT TRUMP!!!



Yep, still applies in all forms of "Motorsports"! 馃槈
 

Registered
Joined
983 Posts
inch is easy but once they start throwing metric at me I am constantly doing conversions in my head.. Oh we are off 10 microns... Hmmm ok about 4 TENTHS ... lol
 

Registered
Joined
25,774 Posts
Nobody has mentioned coated bearings.
I checked the same set of Clevites coated and uncoated and the coated bearings were a few tenths thicker.

So if you got a set of bearings desighed to add .001 clearance and paid for the coating you'd have a set that adds maybe six tenths.
Mix one of those with your current bearings and you might get right what you want.

Caveat: I've read the coating thickness shoud be ignored when measuring clearance.
I'd do some googling, maybe call some tech lines...
 

Registered
Joined
2,682 Posts
^^^^^^^^^^^^^^^ This is correct ^^^^^^^^^^^^^^^^^^^

The thickness of the coating in a typical Clevite coated bearing shell is .00035", therefore the total coating thickness for two shells is .0007". You are better off combining half shells to arrive at target vertical oil clearance, than using the cave-man era practice of "sanding" the backs of bearing shells. However it is not recommended to run a coated bearing shell on the same journal as a non-coated shell.
 

Registered
Joined
2,682 Posts
Yep, and tapered pushrods are superior..............馃槀
Yup! Tapered, or dual tapered pushrods continue to be the design of choice for high RPM race engines . . . . . . .
 

Registered
Joined
5,575 Posts
Yup! Tapered, or dual tapered pushrods continue to be the design of choice for high RPM race engines . . . . . . .
馃槀馃槀馃槀馃槀馃槀
 

Long Live The King
Joined
100,859 Posts
I do it on just about every engine I build. Been doing it for 10+ yrs. I have specific reasons for the bearing clearances I choose and for me, 2-3 tenths is the difference between one application and another. If I want .0025, I make them .0025. If I want .0027, I make them .0027.
Well it's a damn good thing neither you, or Warp worked for O'Neal. He'd fire both of you for doing that. ;)
 
  • Like
Reactions: scott foxwell

Registered
Joined
4,382 Posts
Would sanding the back side of a bearing shell effect the crush designed into bearing housing? I would think it would be difficult to remove a consistent amount around the circumstance. But not being a pro engine builder, just trying to understand.
 

YB Liar and Chief
Joined
29,136 Posts
Anyone ever dyno the engine and then tear it apart and measure clearances again? Or warm to 180* and check?Curious what others results were.
 

Registered
Joined
576 Posts
Discussion Starter #93
Anyone ever dyno the engine and then tear it apart and measure clearances again? Or warm to 180* and check?Curious what others results were.
I was looking into this as well. I saw where Bill C. said, (discussing aluminum blocks) set your normal main clearance. Then heat the main with a propane torch. He said "you will be enlightened". So I did it, he was right.
 

Registered
Joined
4,382 Posts
I used to rebuild some aluminum block hemi truck pull engines. They had hand me down top fuel cranks that had just tiny cracks. Never had any crank/ bearing issues. Those cranks had .006" main clearance cold. No undersized main bearings for standard size. Would have to go .010" to get clearance. Ran several with the standard size. Oil pressure was 150# at idle cold and 50# at the end of the pull. Wonder how much clearance it gained due to temperature?
 

Registered
Joined
5,864 Posts
My Dad was a Tool & Die Maker, was first employed in the aircraft/aerospace industry in Southern California back in the early 1940's. I too have been around machine shops for over 60 years. Therefore I stand by my statement concerning the correct/popular way of stating measurements. In my opinion, when you express a measurement in terms of .xxx" + .xxxx" there exists the possibility of mis-communication, whereas stating this dimension as .xxxx" reduces the possibility of communication mistakes. In this example, .0027" states the exact measurement, no + or - which may be miscalculated.

I have a friend who owns a machine shop in the Houston, TX area doing work for NASA and others. I called him just to get his opinion on the matter and he agrees that .0027" would be stated as twenty-seven ten thousandths in his world. He also made some sort of derogatory statement about automotive machinists being glorified blacksmiths . . . . . . . .
Nasa and SAE tolerancing don't go together. The aerospace industry has been using the metric system for ever. You may want to speak in the terms of Microns when tolerancing aerospace work.
 

Registered
Joined
5,575 Posts
I used to rebuild some aluminum block hemi truck pull engines. They had hand me down top fuel cranks that had just tiny cracks. Never had any crank/ bearing issues. Those cranks had .006" main clearance cold. No undersized main bearings for standard size. Would have to go .010" to get clearance. Ran several with the standard size. Oil pressure was 150# at idle cold and 50# at the end of the pull. Wonder how much clearance it gained due to temperature?
They grow ALLOT!
Kinda is what it is though. The last 2 BAE hemis I've done, both Bryant cranks were .003 under the low side both rods and mains. .0048-.006 seems about all you can do no matter the bearings.
 

Registered
Joined
14,638 Posts
Nobody has mentioned coated bearings.
I checked the same set of Clevites coated and uncoated and the coated bearings were a few tenths thicker.

So if you got a set of bearings desighed to add .001 clearance and paid for the coating you'd have a set that adds maybe six tenths.
Mix one of those with your current bearings and you might get right what you want.

Caveat: I've read the coating thickness shoud be ignored when measuring clearance.
I'd do some googling, maybe call some tech lines...
Clearance s clearance, whether it's to a metal surface or a coating.
 

Registered
Joined
2,682 Posts
Clearance s clearance, whether it's to a metal surface or a coating.
The coating thickness will have an affect on vertical oil clearance. I think this is what the post author is eluding to.
 
81 - 100 of 111 Posts
Top