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Messages - blykins

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1
FE Technical Forum / Re: piston skirt clearance
« on: March 23, 2024, 04:03:19 PM »
I've seen many blocks from ole' Henry come out that were off .020" (not 2, but 20) from end to end on one deck. 

I've even seen some aftermarket FE blocks that were off that bad..............

2
One very interesting video he did was on flat tappet grinding. His findings made me rethink flat tappet problems. I would have posted the video but couldn't figure out how, hopefully the builders on here find it and give some feedback on their thoughts.

The biggest flat tappet cam failure cause is valve spring loads.  I'm not saying that there aren't other causes, but IMO, that's the biggest one.  Cylinder head manufacturers sell all kinds of heads that are "for flat tappet cams" and the valve spring loads are stupidly high.  Nobody needs 140 lbs seat for a hydraulic flat tappet. 

Combining that with the fact that most guys working out of their garage don't check the spring loads, or even know that they need a LOT less than what they have for break-in.  So instead of pulling the inner springs or swapping valve springs, they're bolting heads on and letting it eat. 

3
FE Technical Forum / Re: piston skirt clearance
« on: March 23, 2024, 10:26:46 AM »
Thanks for all the comments , I feel much better about running it as is. I'm not a engine builder or a machinist but have been a truck mechanic for the past 40 yrs. and thought it would be interesting to assemble this engine myself, thinking it would be fairly straight forward but from the beginning its been anything but. Was planning to use my old block but it sonic tested too thin in spots and looking for a acceptable replacement took months and a few road trips. The only good block I could find was a D4TE with the extra main webbing that had already been machined. It looked great ,sonic tested good but had some pitting in one cylinder, thought I could just have a sleeve put in and didn't realize would have to bore and deck it again, 5 months at the machine shop , got it back and installing the camshaft, had to shave two cam bearings to .007 clearance  to get the cam to rotate freely. Then measuring the piston skirt clearance on one cylinder .002 larger than the rest . The main clearances all measured .0025 - .0032 so that was nice but now as I'm mocking up a piston and rod on cylinder no. 4 , it measures .007 in the hole and when I used the same piston and rod in no. 1 it was .005 in the hole.  Is this acceptable ? The machinist is a one man show been doing it for 50 yrs. very FE experienced and a really nice guy, he said he square decked it, maybe he's having vision problems.  Also, when I torque the main caps to even 70 ft. lbs. my camshaft becomes noticeably harder to rotate. Is this normal ? It makes sense to me that if the heads torqued down distorts the cylinder bores, that the mains torqued would distort the cam tunnel. I think I'll install new cam bearings and make a cam cutter out of an old camshaft as Brent suggested and see if that helps. Should fitting the camshaft be done with the mains torqued ?  I'm not looking for perfection , I realize this is a 50 yr. old truck block, just want to know what is acceptable. Even with all these issues, I am enjoying learning this process and feel very fortunate to have this forum with so many good people with so much engine knowledge and so willing to help.

Doesn't make sense that the mains affect the cam.  I've never seen that before.

.002" between ends of one deck isn't really a deal breaker.  Probably just had the block out of level a hair.  Doesn't take much over the length of the deck. 

I don't really care for .007" cam/bearing clearance, but it would most likely run ok.

4
FE Technical Forum / Re: 3U crankshaft
« on: March 22, 2024, 04:42:12 PM »
I had Adney Brown work me up a 391 crank 5-6 years ago.  Did the snout work, did the flange work, turned the rod journals down to BBC size.  It was beautiful until it took about 8 pieces of heavy metal to balance it.

The application should always determine the parts specifications but if I was building an engine that wasn't under big boost, or not running with the throttle on the floor for three hours, I'd probably go with a good nodular crank and a good balance.  Less rotating mass, stiffer than forged, easier to balance, and the budget-friendly solution.  Everyone has their comfort zone.

Sometimes I have to work with what the customer sends/asks. 

5
FE Technical Forum / Re: 3U crankshaft
« on: March 22, 2024, 01:44:04 PM »
      And then you have nitriding, and then you have the balancing affair which will be more time consuming, maybe even requiring heavy metal (both equaling greater costing  :o) than other options; are you adding this all up?  And it's still only probably a 1010 alloy, with a certain sum of fatigue already invested!  ::)

      Yes, I hate the idea of a "chinese" crank, but if you at least buy from one of the better suppliers (pay a few dollars more!) they generally work out O.K..   :)

      Scott.

I had Adney Brown work me up a 391 crank 5-6 years ago.  Did the snout work, did the flange work, turned the rod journals down to BBC size.  It was beautiful until it took about 8 pieces of heavy metal to balance it. 

6
FE Technical Forum / Re: piston skirt clearance
« on: March 19, 2024, 01:52:06 PM »
The fact remains that 4032 is more brittle and it doesn't expand as much as 2618 plus, these are neither Mahle or SBF pistons. There is much more mass to these pistons, than the SBF.

I would diffidently check with RaceTec before installing that piston and he should have file fit rings for the additional .006+ end gap.

If you would read all of his posts, he did check with Racetec.........

I fully understand that these are neither SBF or Mahle pistons, but sometimes you have to do a little deductive reasoning......based on experience......

7
FE Technical Forum / Re: piston skirt clearance
« on: March 19, 2024, 12:41:02 PM »
There are also plenty of 4032 pistons that ask for more clearance and there are some 2618 pistons that want less.  Bore size, shape, and application has a lot to do with it.  Some of the BBF Mahle 4032 pistons want up to .005" of piston/wall clearance.  They also have some SBF 2618 pistons that setup at .0025".

At .0055" clearance, I doubt you'll ever hear anything.   I have had engines come back for freshen-up where we just honed a thou or so out to clean them up and put them right back together. In addition, Randy Gillis, lead sales/tech guy at Racetec (RIP), told me many times to run the 4032 at .005" on some of the applications that I was running.

As mentioned, other than the OCD part of it, I'd have no issue running it.  Just put a note in your build notes so that if you ever sell it, you'll look like you did your due diligence, measured everything, and made the executive decision.

8
FE Technical Forum / Re: piston skirt clearance
« on: March 19, 2024, 04:36:03 AM »
Absolute no on the knurling....

I'd run it. 

9
FE Technical Forum / Re: piston skirt clearance
« on: March 16, 2024, 06:00:18 AM »
Did the shop use torque plates?

10
FE Technical Forum / Re: Spark plugs for BBM heads
« on: March 15, 2024, 04:25:36 AM »
The plug will depend on the compression ratio.  I run 10-11 on Autolite 3323’s and 3324’s.  Higher than that, I usually switch to a colder plug, like a 3910 or similar.

11
FE Technical Forum / Re: Spark plugs for BBM heads
« on: March 14, 2024, 05:06:18 AM »
What's the compression ratio gonna be?

12
FE Technical Forum / Re: oil gallery
« on: March 13, 2024, 03:54:41 AM »
They make extended length taps so that you don’t have to do that.  I have a nice sharp 6” 1/4NPT tap. 

13
FE Technical Forum / Re: oil gallery
« on: March 11, 2024, 02:00:17 PM »
Brent, you apparently don't know what a dry seal plug is.

Your short Pioneer plug, is most likely a a dry seal.

A pipe plug thread gauge will keep a lot of people out of trouble in tapping for pipe plugs.

They have different names, but I was going off of this description, that you typed in:

"The dry seal plugs, had a little different taper and that's why they don't go in as far."

You want them to go in further, not go in as deep.

Could be that we're talking around each other.  Or maybe we're not.  I really don't care either way.

14
FE Technical Forum / Re: oil gallery
« on: March 11, 2024, 12:07:19 PM »
The type of pipe plug that you will need, is called a "Dry Seal". Edit: The dry seal plugs, had a little different taper and that's why they don't go in as far.

In a critical area, you need to use a pipe plug thread gauge to be sure that the thread is deep enough but, as shallow as possible. The gauge has a flat on it, across 3 threads. When you reach those threads, the first is min, next is nominal and the last is max thread depth.

You may not need to drill all the way threw if, you use a pipe reamer. It tapers the hole the proper length for the thread.

You don't want a "Dry Seal" plug.  You want the plug to go in deeper in this area, not shallower.

Pioneer makes all kinds of different pipe plugs for engine scenarios.  Tall, short, drilled, etc.  The short Pioneer plug is the best choice here, don't have to cut them down, just tap the hole and screw them in.

15
FE Technical Forum / Re: oil gallery
« on: March 11, 2024, 11:08:22 AM »
A short Pioneer plug will do the trick without having to cut it/shorten it.  Tap until it will sit below flush and roll on.

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