HELP SBC crank Bearings!!

Oh shit now tell us why someone building a little more HP than stock ( which I think Hyway Hauler is doing) wouldn't benifit from running a very little extra clearance & a good 40 or 50 oil ,rather than spending more money on bearings to pick up .001

 

I looked back at his original post and his answer was ""No not gonna race it,Just need a motor that's gonna last. Now the thick oil only produces more oil pressure when the oil is cold and won't hold adequate oil pressure when warmed up. I have tried this and the result is not good. Refer back to post #17 >>>>.

 

So all your engines are built with in a .001 , is that what your telling me, come on !

 

####Nope wize ass All of my daily rebuilds get a reground crankshaft so i can get the clearance correct !! And when we do a race engine if I don't like the clearance I regrind a brand new crankshaft just to get the clearance right but I can say that the quality of the new shafts usually predicts if it will have to be reground. In my mind building a engine with crankshaft that has incorrect clearances is like building a $500000.00 house on a cinder block foundation !!! It's quickly going to Fail >>>>.

 

Thanks, I failed to mention earlier that the reason I am so upset is whene I tore down the engine, I mic'd the crank because it looked usable, when doing so my mesurement came up almost 0.001" shy of standard. When I brought the block to the shop to get punched out, and to replace the cam bearings, I also brought the crank in to get polished, I asked the machinist to order the proper bearings, thinking that he would measure the crank and get undersized bearings, but when I got home and started preping parts for install, noticed these were STD size bearings, I called him up, asked him why and he told me that the crank with those bearings would be fine, so I put it together and plastigauged it so I would feel better, but the results made my blood boil. When I called him to exchange, he said he wouldn't take em back due to the fact that they had been installed, and then went on to tell me the 0.0036" was acceptable, and to buy a high volume oil pump to bump up oil press. This is why I was seeking further engine builders knowledge, and like I stated earlier, the new 0.001" undersized bearings are on there way...

 

So if I buy a engine from you ,all your tolerance is within a .001, BS just answer the fucking question without trying to give a cool know it all answer. I'll bet every bearing clearance on Hyway Hauler engine is different , he is better off having his engine balanced than worrying about a .001

 

Don't worry fucktard as you will never buy an engine from me !! And the answer is yes !! As thats what the words blue print mean. And I do strive hard to get all of the measurements throughout the engine the same !!!>>>>.

 

Every bearing clearance in every engine that I have ever build are easily within .001" of each other. I take the time to mix and match sets to get things "on the money". It's the right way of doing things. Same thing goes for the largest piston in the largest bore...filing ring end gaps for each bore..etc, etc.

 

Wow, super plus got his panties in bunch over an engine that's not even his? Amazing. Lots of this on here lately, useless anger and insults. I too find that it's easier to invest a bit more time getting things right. Ran the same bearings in a BBC for over 400 drag race passes, that motor going through the eyes at 7800. But then again the bearings were all within .0002 on the rods and .0001 on the mains. Must not have been worth doing, huh?

Back to the original poster, yes .003 is high for a SBC. I don't understand why you simply can't exchange the std bearings for the .001 unders. I had to do that on my mains a couple times for different motors, and it's what most pros and the GM engineers alert us to when you run into high limit situations like this.

Ok I'm done sharing my experiences. We can go back to spitballs now...

 

I personally would be ok with .003..Not ideal , but it will work.
The high volume oil pump thing is another issue.
For many reasons I prefer the z/28 pump instead of the high vol. unit.
Melling # M55A. 302 and 350 h/p.
This pump makes 20% more volume and 20% more pressure than stock.
Just enough increase to help your issue and not enough to cause trouble.

One example (there are several ! ) of the kinds of grief a h/v pump can cause
is the engine in my pickup. I purchased it from my buds at the wrecking yard. Fresh , less than 5k miles.. last owner gave up trying to fix the oil leak. This thing runs sweet, rv cam headers, edelbrock intake..Traced the leak to the valve covers. Good thing this has a 7 qt pan cuz all the oil ends up in the valve covers !! Yup, some fool put an M77HV pump ( it is a 454) in hydraulic cam equipped engine.
I personally have seen, and had to repair several small blocks that starved the pump because of using an hv pump with stock pan and hyd cam.
Good luck.
M55A is a good solution for you IMO.
Dave

 

Ok gents, time friggin out.

There are engine builders and there are "engine assemblers".

This time I'll have to stick up for Engine Pro 5X and the information he gave in his first post 5X ego or not. Reason, Since I have been on this board I have never seen him give anyone bs information or what I viewed as the "wrong" information. He is telling the man how to set up the engine so that he can expect it to last a lot of miles without issues.
Yea we can slap one together with bigger clearances and many of us have and even with the "heavy" oil the oil pressure drops to the bottom at every stop light.

I've learned this, there are certain people on the HAMB like Engine Pro who'd advice you can trust as they honestly work at giving the right advice and then there are those bs artists who always seem to chime in often with misinformation or quite often "get by" suggestions. I don't believe suggesting using heavy weight oil or going to a high volume oil pump to attempt to compensate for loose bearing clearances is solid information in this case. Get by, yes but solid info no.

 

Mr48 chevy, You've just hit on the reason I no longer chime in on discussions of this nature. Having owned a high performance engine shop for years (specializing in Chevrolet big and small blocks) and having my stuff go head to head with the best in the business I used to be entheusiastic about sharing my experiences. After being told to go pound sand by some wet behind the ears 20 year olds with a basic Craftsman tool box and a junkyard 307 to their credit I'm not interested. I'm not going to save the world when it's not appreciated and ruin the opportunity to watch the internet equivalent of the Key Stone Cops.
The right information has been given about the current discussion. The origional poster can pick his choice of who he trusts. If he picks wrong he'll experience what thousands of others have done and the lesson will be learned just like us old timers did it. After all that's TRADITIONAL and another component of this board, right?

Frank

 

Engine Pro 5X is right on the money.
.003 will work but its not what you want for a daily driver.
Going too .001 under bearings was the right way to go.
Next time believe your mike... you said it measured .001 under minimum.
The machinist didn't do a very good job on the mike and polish job... wonder how the rest of his work is?
Keeping your work to .0001 -.0002 is very do able.

Oh... I built a lot of engines with big block pumps on a small block (not necessary in my opinion... but thats waht the customer wanted) and never had a problem "filling the heads" with oil and starving the pump...thats BS.

I owned and operated a Performance engine machine shop for over 15 years.
We did everything in house... crank grinding, balancing, porting, dyno etc.
So I do have some experience backing me up.

 

Again thanks for all the input.

 

Wise Ass, Fuckard , that's nasty ,and just when I was going to order one of your perfect motors , I would suggest Highway Hauler check all his bearing clearances

 

Engine Pro 5X,you said that when building a race engine you grind a new crank to the proper clearance. Wouldn't a race engine use a new crank that's got a surface hardness treatment like Nitriding,and the grinding will remove the treatment?
the treatment goes in at least .005 and you're only shaving a touch?

 

#### You are correct !! But go back and re-read the post !! As I said Quality Would Predict If The Crankshaft Would Need Reground !! Cheeper shafts that people bring me sometimes are not in spec and guess what the cheaper shafts aren't nitrided either !!! >>>>.

 

Ok while we are on the subject of crankshafts and nitriding and getting you moneys worth I'll throw some more chips on the table !! This is a Crower that is one of the nicest pieces that money can buy. This one is in perfect spec and to top it off when Crower made the crank they took the balance weights and designed the crankshaft around the weights !! There are No Holes drilled in any of the counter weights !! Now tell me you don't get what you pay for !!! >>>>. AND OH YEAH DO TO SOME FUCKING WIZE ASS RETARD WE SURE HAVE STRAYED WAY OFF OF THE ORIGINAL THREAD !!!! >>>>.<center>
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I've been avoiding this discussion like the plague, for the reasons mentioned by fab32, but I will toss this in.

I won't use the word "all"...but many new cranks (meaning new from the manufacturer, not meaning "new" as in reground) are off dimensionally, in my experience. This ranges from $200 Chinese sourced-&-machined cranks, to the Scat 9000 series (China-sourced but US finish-machined), to $2400 billet cranks. It happens. And, they get checked & corrected. If they were nitrided at the start....and the nitriding needs redone, well....shit happens...it's racing. The more you pay, the less often it happens...and it may go back to the manufacturer instead of going to the machinist...depends...but it does happen.

Many builders prefer to use untreated cranks for this reason, and have them finish nitrided (or whatever treatment is preferred) as the final step. Moldex is one of the few specialists left who can still do true nitriding.

Nearly all the GM steel cranks I've seen that were nitrided are off from the beginning, at least the recent ones.

 

Ottoman, My pump of choice for RACE wet sump small blocks is the M77. This is std volume (NOT M77HV ).. Solid lifter, restricted oil to the top end, race spec clearance on the crank,etc...... Again, My Choice !

My post refers to otherwise STOCK, hyd. lifter equipped engines having issues with HV pumps.
High volume and or high pressure pumps will work in the proper application, BUT in my opinion have no place in a stock,hyd cam engine.

Engine pro is right on the money ! I have not EVER seen him post bad advice. BTW, new cranks of all price levels need to be checked. VERY few are perfect out of the box !
Dave

 

I agree. Of course when pushing the (marginal) max limit tolerances, when the oil is cold, pressure will be great, and when it gets hot you will observe a pronounced decrease, kind of like when a motor gets worn out................

 

WOW!!! who would of known that bearing clearance could be a pain in the ass. The good thing is that you atleast checked your bearing clearance which is always good thing to do. Good luck on your build.

 

Always happy to see someone invoke the sacred "pump the pan dry" thing...

 

Hey, back on the bearing question....

I was going to mention earlier and forgot, I was taking my assembly in to the shop for balancing with the crank in the block with y new bearings. They were some generic bearing the previous owner or machine shop had put in. They measured out with plastigauge at .0026-.0030 on the mains and slightly tighter on the rods. I really would have liked them a half thousandth tighter all around.
Well, the kid at the receiving desk wasn't listening when I told him that those were new bearings and hence threw them away when he pulled the crank to be balanced, thinking they were used. The shop made good by giving me new bearings all the way around. This time it was Clevite, same spec, std-std. They were a little over a half thousandth tighter. The mains measured out at .0022-.0025 on final assembly. I credit Clevite for making the right stuff, so you might watch out for generic bearings. It was also taught to me a long time ago that you can mix and match the halves in a set to adjust every journal. I did that, too, moving a tight shell to the loose journal to bring them into the middle.

I suspect all these wise contributors covered that same stuff, but you can never be too sure around here.

 

For christs sake, it a SBC, just bolt it together and let it scream!!!

 

No your the one who strayed,and stared the name calling , you should have said from the first , that you are the only person to ever build a fuckin motor

 

ok look at the side of this engine block ... is that a merlin block .... >?

 

Never questioned your race choices... just have never seen any problems with HV or HP pumps on stock or race engines.
All I have ever noticed with a HV or BB pump on a small block was higher oil temps.... probably from the pump bypassing all the extra oil the pump was putting out.
If your clearances are right a stock size pump is more than adequate and takes less power to drive.
Remember if you have 60 PSI (on the gage).. well... you have 60 PSI... doesnt matter how big the pump volume is, once you hit relief pressure the excess oil is just going around in circles in the pump.

 

Holy shit!, never would have thought that this question was going to create a huge cluster fuck, I went to work for 14 hours, and BAM! but thanks for all the input..

 

Good luck with your bearing problem you think you have , finnie