Performer RPM mis match

68galaxie wrote:Good luck with the 0.002 clearances!
I don't run 20 50W oil anymore either - don't underestimate my education level either.
I didn't insult you!
Why do you answer with such a negative attitude?


Cheers

You need to quote under who you are talking to. I'm open to all advice even if I didn't ask for it. And appreciate it. I may not use it , but I appreciate.

All I as attempting to do was offer sound advice to someone with an FE.
You had the need to jump down my throat saying I need to get educated.
If you don't agree with 0.003" main clearance on an FE that is fine.
I always suggest larger clearances when the condition of a block and crankshaft(line honing, squaring, crank straightness etc.) may not be known. Many FE builds are not exactly blueprinted builds.
Sure for a cross bolted block that has thoroughly machined and a trued crankshaft etc. I would use tighter clearances. A standard 2 bolt FE thin wall block is not exactly a rigid starting point - hence the need for a little more clearance than your typical 385 series build.

Back in the day 0.004" was typically used in FE's to have bearings live.

68galaxie wrote:All I as attempting to do was offer sound advice to someone with an FE.
You had the need to jump down my throat saying I need to get educated.
If you don't agree with 0.003" main clearance on an FE that is fine.
I always suggest larger clearances when the condition of a block and crankshaft(line honing, squaring, crank straightness etc.) may not be known. Many FE builds are not exactly blueprinted builds.
Sure for a cross bolted block that has thoroughly machined and a trued crankshaft etc. I would use tighter clearances. A standard 2 bolt FE thin wall block is not exactly a rigid starting point - hence the need for a little more clearance than your typical 385 series build.

Back in the day 0.004" was typically used in FE's to have bearings live.

Easy there bud, you need to look back at who you are addressing I never told you you need to get educated.

Read back a few post and figure out you you need to dress down............... It ain't me:evil: 

You are correct - my apologies.

I started seeing red after reading rm's reply
Most members responses on this forum are usually good natured and informative - not confrontational.

My reply should have been sent to rmcomprandy.

Cheers

68galaxie wrote:You are correct - my apologies.
MOst responses on this forum are usually good natured. I guess rm is different than most.


My reply should have been sent to rmcomprandy.

Cheers

   No problem.............. Apology accepted

68galaxie wrote:Good luck with the 0.002 clearances!
I don't run 20 50W oil anymore either - don't underestimate my education level either.
I didn't insult you!
Why do you answer with such a negative attitude?


Cheers

I sure didn't mean that as an insult or sarcasm. Sorry I hurt your feelings.

I guess because of your advanced education level you interpreted it that way and you don't need to educate yourself about anything, after all ... you must already know everything.
(Now, THAT was sarcasm).

I have successfully run and know a lot of Super Stock FE racers who run .0018" main bearing clearance all the time ... however, they do also run first class parts.
It is not WAAAY to tight.

By the way ... being that you are so educated you should be able to tell everyone what the published by Ford Motor Company minimum main bearing oil clearance is allowed for a 427 dual quad high riser FE. OR, even a top oiler 427 marine engine.
Have you got any idea...? (More sarcasm)  

And you actually assemble and sell race engines based on factory minimum bearing clearances? I would hate to be one of those customers.

"I have successfully run and know a lot of Super Stock FE racers who run .0018" main bearing clearance all the time ... however, they do also run first class parts.
It is not WAAAY to tight."

I agree with you!

However the original poster does not have super stock block, crank, rods, and first class machining.
In his case 0.002" is not enough!  0.0025 minimum with modern oils - Joe Gibbs etc..

68galaxie wrote:"I have successfully run and know a lot of Super Stock FE racers who run .0018" main bearing clearance all the time ... however, they do also run first class parts.
It is not WAAAY to tight."

I agree with you!

However the original poster does not have super stock block, crank, rods, and first class machining.
In his case 0.002" is not enough!  0.0025 minimum with modern oils - Joe Gibbs etc..

He is not making that kind of power either.

Hello Blake,

Take a look over at the FE forum where plenty of very experienced FE builders reside. I asked a simple question regarding FE bearing clearance. Interesting reading. Take it for what it's worth.

http://www.network54.com/Forum/74182/thread/1377699504/428+main+bearing+clearance

Cheers

Not exactly pertaining but, close.
"If 40.000 people believe in a dumb idea ... it is still a dumb idea". Ben Franklin

I would venture to say that only some of those responders actually are an engine builder FOR A LIVING.  If dentistry was their hobby, they would have an opinion on fixing teeth, too.

EDIT: I actually read those responses and SOME are engine builders so I have edited my response.

You must not be a very busy "professional" engine builder seeing that you spend nearly all day on this forum providing your 0.02$ worth about engines you have little experience building.

Cheers

68galaxie wrote:You must not be a very busy "professional" engine builder seeing that you spend nearly all day on this forum providing your 0.02$ worth about engines you have little experience building.

Cheers

I walk past this computor a few times a day and I do sit down for a few minutes at a time.

By the way ... Barry and I are pretty good friends and being SAFE always gets more clearance which is not necessary except in cases where the end user doesn't know what he is doing and treats the end product as if it were an anvil.

Little experience with an FE...?  That's funny.

You should post this on that other forum, too.

Randy has probably built more FE engines than anybody here - with one possible exception - and that's probably close...  

This got cross posted on the FE forum as well - so we may as well keep it up on both ends so nobody else gets confused as responses go back and forth. It's actually possible to agree with everybody because there is no single "correct answer" even if we really want one. Instead we have a range where multiple values "will work", and the builder gets to choose the strategy that makes the most sense to him and his circumstances.

I'll explain a couple thoughts. While I worked at F-M I asked the lead bearing engineer about clearances - a guy whose customers included Ford Motor Company, and a man who handled the design and material work on the race bearings simply because he thought racing was cool. I wanted the real answer just like we all do. He told me that "when clearances were over .003 his phone rang, when they were under .003 his phone did not ring - therefor the correct clearances were under .003". He also told me that the rule of thumb having .001 per inch of journal diameter was a damn good place to be - and you'd never have a problem there.

Those comments as applied to an FE's 2.750 main left me with a pretty narrow main clearance range of .0027-.0030. After clipping together a bazillion FE engines using that range I'd have to say it works just fine and I have not had any reason to move away. On aluminum blocks I do tighten it up to .002 to compensate for block growth, and I know that really good parts in a very well refined race package can run much tighter to take advantage of extremely light oil ring tensions. But 99% of the FE builds are not racers at that level, and the risk of being too tight outweighs the costs of being a bit loose.

Barry_R wrote:Randy has probably built more FE engines than anybody here - with one possible exception - and that's probably close...   

This got cross posted on the FE forum as well - so we may as well keep it up on both ends so nobody else gets confused as responses go back and forth.  It's actually possible to agree with everybody because there is no single "correct answer" even if we really want one.  Instead we have a range where multiple values "will work", and the builder gets to choose the strategy that makes the most sense to him and his circumstances.

I'll explain a couple thoughts.  While I worked at F-M I asked the lead bearing engineer about clearances - a guy whose customers included Ford Motor Company, and a man who handled the design and material work on the race bearings simply because he thought racing was cool.  I wanted the real answer just like we all do.  He told me that "when clearances were over .003 his phone rang, when they were under .003 his phone did not ring - therefor the correct clearances were under .003".  He also told me that the rule of thumb having .001 per inch of journal diameter was a damn good place to be - and you'd never have a problem there.

Those comments as applied to an FE's 2.750 main left me with a pretty narrow main clearance range of .0027-.0030.  After clipping together a bazillion FE engines using that range I'd have to say it works just fine and I have not had any reason to move away.  On aluminum blocks I do tighten it up to .002 to compensate for block growth, and I know that really good parts in a very well refined race package can run much tighter to take advantage of extremely light oil ring tensions.  But 99% of the FE builds are not racers at that level, and the risk of being too tight outweighs the costs of being a bit loose.

Hi Barry ... I agree totally.
My disagreement was with the ABSOLUTE, vehement statement ... ".002" is  way  to tight for main bearing clearance even on a street FE. A performance build should be .003" ".

That is just not such an absolute fact in a way as to boisterously play the superior role and correct someone who is contemplating using clearance a bit tighter.

Found the post...

I think things got a little twisted up between forum conversions.

My apologies for getting my shorts in a bind on the FE forum. It seemed like there were a lot of "absolute" statements going on, and I should have looked for this thread harder and read it myself before posting.

Randy, got your email. Sent you one back.

I think we're pretty much all in agreement from what I can tell. That gives me a warm squishy feeling.

Ain't forum life fun?

A true double edged sword - we all get smarter but we all risk un-necessary arguments as well - impossible to "see" the normal body language and eye contact of a real "in-person" discussion.

Amen.

I think we can agree that some builders choose tighter bearing clearances than others.
My experience (much less than Randy's) has been running 0.003" on FE mains -never ever had any issues)
I was not telling Randy he should use 0.003" clearances.
I suggested to a poster that 0.002" was too tight - in my opinion.
You all know how the response was - how dare anyone suggest 0.002" was too tight?

I am sorry if anyone (other than me) had ruffled feathers. I have run FE's since the early 80's and have never had a bottom end issue on any of them. Running a bit looser certainly doesn't hurt anything, but run a bit tight and it can certainly hurt the wallet. That's all I am saying.

Cheers guys!

0.002651

Well being this is my engine we are talking about here, I will tell you why I have the clearance at .002.

This is a good friend of mine, it's a street engine being held to around 5500 rpm, maybe a bit higher from time to time, I settled on a cam of 230 - 236 on a 108 I cant see this being a problem.

I have built several FE's over the years and with pump gas cast heads ported and non ported, and some with more compression, I have never had a bearing problem. The longevity of the engine is part of the decision of the clearance also. I just felt like if he was going to put a ton of miles on this deal, I didn't see any need to set them wide and be on the high side right out of the gate. This will also be a 10-30 oil deal too.

I don't see the need to turn a 428 to where the .002 will be a problem. How many people out there have taken a stock low mile FE back in the day and added a cam headers and manifold, and turned the crap out of it? I'm talking torturing it......... And never had a problem, and it on factory specs.

Like I said I appreciate the advice, but my name is on this deal and I will build it as I see fit. It ain't my first goat roping either.


This started because I was amazed at the difference in the ports between two supposedly same family and category engine pieces, RPM VS RPM.

richter69 wrote:0.002651    

 

61coon wrote:

richter69 wrote:0.002651    

 

X2 !! That's the EXACT number I demand from The Shop.  

cletus66 wrote:

61coon wrote:

richter69 wrote:0.002651    

 

X2 !!  That's the EXACT number I demand from The Shop.   

The 0.002 is the easy part...you won't get the 651 just anywhere, but somehow it's easy to get here. 

Blake...
Anytime you use clearances which will necessitate a high volume flow amount of oil, every time you cold start it, as you constantly would in an everyday street vehicle, the flow of oil required to go through the filter will not be able to keep-up with the oil demand.
Hence, the filter by-pas will open and by-pas unfiltered oil into the galleries, (and of course, through the bearings), until the oil warms enough to be able to pass freely through the filtering element.

Keeping the oil demand as low as it can possibly be and still have no bearing problems, (other than to much trash going past them from an open filter by-pas), is the target here.
Finding that target is the goal...