440 Rebuild

[Challenger340]

* NEVER attempt to polish a Crankshaft more than "maybe" a TEN-Thousandth or so.... and certainly NOT as a way to gain more bearing clearance.
You GRIND the Crankshaft to LOWSIDE.... then Polish to provide surface finish only.

When Blueprinting for HP Street or Racing Engines
* By GRINDING the Crank to LOWSIDE or SMALL side of the tolerance, you allow yourself extra .001" "room"... to then "SET".... or "ADJUST" the Bearing Clearances according to the intended application when ReSizing the Big Ends of the Con Rods(or main W/Line Honing).... by either ReSizing the Rods to the "Small" or conversely "Big" end of their size tolerance range(typically .0005").
Remember here.... because of Bearing eccentricity which is built into the Bearing shells....
and
the effects of Bearing "Crush" when the Bearing is Torqued up in the Con Rod(or Main).... the INCREASE or DECREASE in Bearing Clearance is NOT linear UP/DOWN as either the ConRod Big End or Main Cap size is opened/closed within tolerance. That typically .0005" Rod Big End or Main cap Size tolerance when adjusted can see actual "vertical" Bearing clearances move .0007"/.0008" UP/DOWN as the "Crush" under Torque is applied.

In this case for this type 440.... by very simply following instructions and grinding the Crank LOWSIDE.... and sizing everything else Rod Big Ends/Mains "midsize" as is common practice at farm implement/NAPA shop syle houses .... you will end up right around .003+" mains and .0025" Rods.
The actual Crank GRINGING to lowside one of the hardest things to get Farm Implement/NAPA style Machine Shops to do.... don't ask me why but it is.... because they just can NOT seem to wrap their Heads around pressure/rpm/load/cushion effect Oil requirements for High Performance ?

 

[MoparHusker]

In this case for this type 440.... by very simply following instructions and grinding the Crank LOWSIDE.... and sizing everything else Rod Big Ends/Mains "midsize" as is common practice at farm implement/NAPA shop syle houses .... you will end up right around .003+" mains and .0025" Rods.

I think this is where it is a little confusing. If I tell the machinist to grind to the low side of the tolerance, let’s just say on the main journals, this assumes he knows what I am talking about. So, the factory main would have measured at 2.750 inches. Did we say that factory clearance was .0015? If we grind the mains .0010, down to 2.740 and get .0010 bearings, shouldn’t my clearance still be .0015? If I wanted to have a finished .0030 clearance, assuming I will take off .0001 with the polish, wouldn’t I grind .0024, taking the main from 2.750 to 2.7476. Then you polish it to remove the last .0001 for a finished size of 2.7475? If that is the case, why couldn’t I just tell the machinist to grind the main to 2.7476 and finish polish it?

The guy seems to be pretty smart, so I may be worrying over nothing.

I would not have an inexperienced person assemble your motor. I learned by having my very experienced speed shop owner and assembler show me step by step how to do it correctly. That guy was so meticulous it still amazes me. He had different vendors for all the actual machine operations that he had total confidence in. Then he triple checked their work.

I think the machinist is pretty experienced. If you were referring to me, I am inexperienced, but I have rebuilt an engine, although it was a V-6 Chevy. Obviously this one is different, since I can’t just go down to the junkyard and pick up another one if something goes wrong. I don’t know all of the nuances, but at the same time if you pay attention to what you are doing and not be afraid to ask questions if you don’t know something, you should be okay.

I did request the three main rebuild books for Christmas, so I have the one CuriousYellow mentioned as well as the one by Don Taylor. I am forgetting the third one at the moment.

 

[66Satellite47]

Husker, there are different levels of experience for the machinist AND the assembler. See post 141 regarding the machinist experience. As far as the assembler, I would suggest having an experienced BB Mopar assembler "coach" the newbie on the fine points of HP engine assembly. Reading a great book such as Andy F's is a good start, but not the same as having done it many times to learn the techniques needed. Just my opinion.

 

[4406bbl]

I think this is where it is a little confusing. If I tell the machinist to grind to the low side of the tolerance, let’s just say on the main journals, this assumes he knows what I am talking about. So, the factory main would have measured at 2.750 inches. Did we say that factory clearance was .0015? If we grind the mains .0010, down to 2.740 and get .0010 bearings, shouldn’t my clearance still be .0015? If I wanted to have a finished .0030 clearance, assuming I will take off .0001 with the polish, wouldn’t I grind .0024, taking the main from 2.750 to 2.7476. Then you polish it to remove the last .0001 for a finished size of 2.7475? If that is the case, why couldn’t I just tell the machinist to grind the main to 2.7476 and finish polish it?

The guy seems to be pretty smart, so I may be worrying over nothing.




I think the machinist is pretty experienced. If you were referring to me, I am inexperienced, but I have rebuilt an engine, although it was a V-6 Chevy. Obviously this one is different, since I can’t just go down to the junkyard and pick up another one if something goes wrong. I don’t know all of the nuances, but at the same time if you pay attention to what you are doing and not be afraid to ask questions if you don’t know something, you should be okay.

I did request the three main rebuild books for Christmas, so I have the one CuriousYellow mentioned as well as the one by Don Taylor. I am forgetting the third one at the moment.

The factory specs call for 2.7495 minimum on main journals, 2.374 on the rod journals. If you do that with 119m bearings you should get .003 on the mains and .0025 on the rods. The way 340 says to do it is really good. It all depends how good the crank guy is. If he is perfection you could finish the block and rods to middle, install the bearings, measure them, then give the crank guy the exact figure you need. Do not follow the minimum factory CLEARANCE specs out of the service manual.

View attachment 1239307

 

[dvw]

If the guy grinding the crank doesn't know what the low limit is, he's not the person that should be grinding the crank. If the main bore and the rod bores are correct the bearing clearance is going to be in the ballpark. Always check as there could be the rouge off sized bearing. As you are seeing first time engine building has many unknowns. It's hard to know what's really important, somewhat important, or barely matters. The basic things you need to remember. Make sure you have enough clearance, to tight is bad. Make sure everything is clean. Take your time. if something feels wrong STOP. I met plenty of "mechanics" working in the auto repair industry starting in 74. Many of them knew which parts went where, and how to tighten the bolts. Nothing more. I was fortunate when I was younger to work with Dave Koffel. He taught me a lot.
Doug

 

[MoparHusker]

I have talked to the machinist multiple times and he has never given me a reason to think he does not know what he is doing.

I just have not had in depth conversation about grinding to the low side and these finer details. I am sure most people just bring in there blocks in and he takes care of it. I am guessing he probably thinks I am a huge pain in the arse. That is okay though, just want to make sure it is done correctly.

I passed along all of the information Challenger gave me and the machinist has ground the crank. I will most likely see him on Friday and I will get the lowdown. He is going to have to mock things up anyway to get the down in the hole measurements, so the block can be milled, so maybe he can check all of the clearances to make sure they are correct.

 

[66Satellite47]

If the guy grinding the crank doesn't know what the low limit is, he's not the person that should be grinding the crank. If the main bore and the rod bores are correct the bearing clearance is going to be in the ballpark. Always check as there could be the rouge off sized bearing. As you are seeing first time engine building has many unknowns. It's hard to know what's really important, somewhat important, or barely matters. The basic things you need to remember. Make sure you have enough clearance, to tight is bad. Make sure everything is clean. Take your time. if something feels wrong STOP. I met plenty of "mechanics" working in the auto repair industry starting in 74. Many of them knew which parts went where, and how to tighten the bolts. Nothing more. I was fortunate when I was younger to work with Dave Koffel. He taught me a lot.
Doug

Doug, you learned from one of the BEST. Your advice sure seems spot on to me.

 

[4406bbl]

I have talked to the machinist multiple times and he has never given me a reason to think he does not know what he is doing.

I just have not had in depth conversation about grinding to the low side and these finer details. I am sure most people just bring in there blocks in and he takes care of it. I am guessing he probably thinks I am a huge pain in the arse. That is okay though, just want to make sure it is done correctly.

I passed along all of the information Challenger gave me and the machinist has ground the crank. I will most likely see him on Friday and I will get the lowdown. He is going to have to mock things up anyway to get the down in the hole measurements, so the block can be milled, so maybe he can check all of the clearances to make sure they are correct.

Keep in mind this, you have been given great advice that took many here years and $$$$ to learn, AND I bet your machinist is learning things from it also. Never make an excuse or feel like a pain to get something right. In the end maybe this will be another shop that can get it right for the next guy, if everyone puts the pride/know it all attitudes down.

 

[MoparHusker]

The factory specs call for 2.7495 minimum on main journals, 2.374 on the rod journals. If you do that with 119m bearings you should get .003 on the mains and .0025 on the rods. The way 340 says to do it is really good. It all depends how good the crank guy is. If he is perfection you could finish the block and rods to middle, install the bearings, measure them, then give the crank guy the exact figure you need. Do not follow the minimum factory CLEARANCE specs out of the service manual.

So, the picture you are showing is not the service manual I assume? So, you are saying that the factory spec minimum is 2.7495 and if the crank guy grinds it to that spec, the 119m bearings would put me right at .0030 clearance on the mains? I assume you are talking about the standard 119m and not the 119m-10? So, is it possible that on some areas of the main journals then that if the crank was already at that measurement, nothing would be removed? He told me he was going to take .010 off of main and rod journals, which he has already done. Since grinding to 2.7495 would be perfect for the 119m, should I assume that taking .010 off of that number, make it perfect for the 119m-10, so grind it to 2.7395?

The only way I am seeing this getting to the correct numbers at this point is for him to put the bearings and crank in with some plastigage, torque it down, take it back apart and see where we are at. Then, depending on that, he may need to do some more grinding.

I would concur there has been awesome advice given and i am trying to interpret all of it and then regurgitate it to the guy doing the work. If he was strictly a Mopar guy, he probably would have said he knew exactly what I was talking about. I never assume anything, so we will have to see what the numbers say.

 

[4406bbl]

That is the factory service manual, the specs are for a standard crank, just subtract .010 if you grind it....just do not follow the CLEARANCE specs, you want more. .003 and .0025. I guess if it is ground you will have to see what you have. I doubt he will use plasigage, a mic and dial bore gage is what an engine builder would use.

 

[MoparHusker]

I started researching the damper/harmonic balancer. Seems like there are some that like the fluid dampers and others say stick with the elastomer.

Some of these appear to be too tight going on the crank. Others have an issue with holes lining up.
I have looked on Summit, Mancini Racing, 440 Source, Jegs and some others.

I probably am inclined to go with the elastomer version. I did verify on my pulley that I will need the offset and not the symmetrical pattern. What about the weight of the balancer itself? It seems to me like the heavier you go on the balancer, the more power it is going to take to get it spun up. Is that incorrect thinking? What weight should I be targeting. I do like the looks of the Pro Race Products Pro Sport on the Mancini site. I think I saw somewhere that this is made by Romac. Also, does the O.D. Make a difference? Stock is supposed to be 7.25. What should I be shooting for? Is smaller better? Can the bore be honed if it is a little tight? What about thickness? I think stock is 1 inch. How many of these have pulley alignment problems?

As always, everyone’s help is much appreciated!

 

[66Satellite47]

Husker, if the crank is .010/.010 under mains & rods. Some models of mains do have the extra .0005 built in, some don't. I would expect a good performance machine shop to use the mic & dial bore gauge. Plastigage is not what I would use.

I observe that the choice between a fluid damper & elastomer is personal preference. I had an old Fisher clutch style for a while, seemed OK. my last two have been ATI elastomer. Some are tight going on the snout. I have run a brake hone through a couple times to loosen the fit a bit. Stick to the stock diameter. The pulley alignment can be a pain.

 

[Curiousyellow71]

The weight change from one damper to another isn't likely to be of any significance. Keep in mind your bolting a really big and heavy torque convertor on the back end of this engine. It's going to offset most anything you are doing on the engine internally. Usually fluid damper we use when we are shifting 6k or more or required nhra racing . Been using oem on most all our others. I'd be surprised if the rubber in any of the new dampers lasted like oem has. I've heard of dampers being tight on the snout across multiple brands but haven't dealt with myself yet.

 

[MoparHusker]

I was considering these three harmonic balancers:
PowerBond PB1112ST:
https://www.summitracing.com/parts/pbb-pb1112st

Pro Race Products Pro Sport 34279:
https://www.manciniracing.com/chv838inhe1.html

Romac 0215:
https://billmitchellproducts.com/pr...ternal-odd-bolt-pattern-click-here-more-info/

I think I will most likely go with the PowerBond, as long as it has the odd bolt pattern. I left a message for their technical guy to call me back. Looks like it spins up to 6500 rpm, so that should be sufficient.

 

[Curiousyellow71]

I think the powerbond would be good if you can find one. If not I think this pro race unit would be ok.
https://www.manciniracing.com/prostreet1.html

 

[4406bbl]

I just would not trust one made in China. The romac seems like a bargain if will fit and not China. Check out damperdoctor.com for a reman, but mainly he explains why factory balancers are better than China for the rubber style. I have used new mopar or fluidampers on my stuff. I don't worry about the bolt pattern as you just need to elongate one hole.

 

[SlinktRR]

have you looked at the ATI super damper?

 

[MoparHusker]

have you looked at the ATI super damper?

I have taken a look at them. They are twice as much as I was really wanting to spend. Looks like the are very nice, just too pricey.

I did go ahead and order the PowerBond. With a price match it brought it down to $149.78. A new pulley price is too much, so I measured the old pulley and as 4406bbl, said, I would only need to elongate one hole and that is by 1/10 of an inch.

Thank you for the feedback!

 

[SlinktRR]

Yep I went with the summit racing bracket SFI it's a solid damper for around $150. That is probably the minimum price range to target. I would have liked to use the ATI though, next time.

 

[MoparHusker]

Ok. The information we have all been waiting for.

I dropped off parts with the machinist today, Kevin, at Arnolds Motor Supply in Ankeny, IA. We had a very good conversation and I appreciated him taking an hour of his time to talk to me.

He indicated that all of the things we had talked about and all of the information I provided to him were things that he knows. There wasn't anything new for him. He is very experienced. Said he has done a $70,000 race motor, pulling tractor motors, circle track motors, mopars, and etc. I have a very high confidence level in this guy after our conversation and if I am ever in a position to have another engine to build, absolutely would not hesitate to take it to him.

In retrospect, if I would have had him mic the main and rod journals first, then let me know if a .010/.010 grind was sufficient, I could have ordered the appropriate bearings and provided to him. At that point he could have had the align hone done and could have determined the bore with the bearings to determine how much he needed to grind. As I have said previously, I was not tracking what the Low side tolerance was until it was pointed out.

I told him that we just had not had the conversation about what his experiences were, so I did not know what he did or did not know. So, if you have a very experienced person, I am sure it could be a little offensive if someone questions there credentials. I do have the same thing happen at my work from time to time and then I am able to tell them or demonstrate to them that I know exactly what needs to be done. One person I had to take it a little further and get to the point of explaining to them what relational databases were and how they worked and what I was proposing was the appropriate solution.

Anyway, I truly appreciate all of the feedback and input from everyone on this forum. I know that through your contributions to my knowledge, the engine build will be pretty awesome when it is completed.

I have full confidence in Kevin getting things done and done correctly.

Thank you again!