I had bought some ARP main bolts to put in my 4-bolt main 454. The machine shop went ahead and put the shortblock together for me for some reason, which is OK I guess. But he used what appears to be GM bolts or some other bolt than ARP on the mains. Now, the long bolts are all uniform (i.e. same pattern on the head) and the same goes for the short bolts...I'm basically getting at it's not like he just reached in a bucket of bolts and used whatever he pulled out.

When I was going to install the main bolts, I read on the thing that if other bolts were used to align hone with then changing fasteners would cause problems (don't remember exactly why it said though...different tensile strengths or something).

Part of me wanted to use ARP main bolts for peace of mind...but then again the guy does know what he's doing and it is a 4-bolt main...so would changing them mess anything up or would I really be okay just to use what he has and send the bolts I got back for credit?

Thanks guys for the advice...

I'm sure the machine shop wouldn't put just any bolt in. Changing to the ARP bolts shouldn't hurt anything.

This is a quote from ARP (When changing from factory fasteners to high strenth fasteners, clamping force and tolerances WILL change. The main bores should be aling honed using the fasteners which will be installed at the recomended proeload)

Any blocks or engines we build that come through our shop we ALWAYS line hone them and replace the stock hardware to ARP and we have never had any problems using this procedure.

Learn something new every day. I thought if you torgue a bolt to a certain number it didn't matter what bolt. I guess certain grade bolts react differently.

I've changed to arp main bolts in three motors and had no change in main bore measurements without align honing them. Rod bolts are a different story for sure.

My experience mirrors that of Bob's(name?) I've done three, one 454, and two 350's, and no change. One of the small blocks was changed to ARP studs, and still no need for align honing. It can, but does not normally affect the bore. Especially unlikely if using bolts. Going to studs, it would make more of a difference, as you're not turning the threads in the block when you're torquing. As mentioned above by Bob, rods can be affected if the bolts register the cap. If the rods have dowels, then the bolts have little effect. Main caps are not registered by the bolts, but rather by the block.

I've heard the reasoning for the need to check the crank bore when changing bolts, or to studs, and it supposedly has to do with the stronger bolts "pulling" on the cast iron of the block, creating a high spot on the block, and causing the caps to lift slightly! This makes no sense, as align honing could not correct such a condition! It could correct an out of round condition caused by this, but I still wouldn't want my caps dancing in this manner! This was explained to me by a couple different machinists, yet they rarely perform an align honing due to changing the fasteners!

JMHO, leave the bolts in there, you'll be fine. If you don't trust their work, borrow a good torque wrench, and check them. Steve

I just put ARP studs in my BBC and the bores did move. Had it line honed. WHen you line hone it you slightly trim the bottom of the caps to make sure everything is correct. My caps weren't flat to begin with so this may have something to do with it.

In order for a fastener to "work", meaning retain the load properly, you must stretch the fastener, it is not the torque that does this, it is stretch (you tighten a bolt to get a stretch). Since you can't easily measure the stretch in a main bolt, you use a recommended torque to achieve what is hopefully this stretch. This is why using the proper lube is critical as it affects this. If you have no stretch, but a lot of torque, it will fail.

When you go to an ARP bolt, which is usually of a higher tensile strength, you must use more "torque" to get the adequate stretch. If you stretch it too much you go into a plastic deformation, rather than elastic and the fastener will yield and fail.

Most new cars use a torque/angle tightening which may be the most accurate yet, and is more suitable for high volume.

Originally posted by baddbob71:
I've changed to arp main bolts in three motors and had no change in main bore measurements without align honing them. Rod bolts are a different story for sure. There would not be a change unless you torqued, or stretched the ARPs to their recomended load.
If you don't, there is no sense in using ARP.
Might just as well keep the original or OEM bolt.

There may be a slight change in the tolerances, but they are probably so minute that you wouldn't have a problem with bearing tolerances on the mains. I have never seen ANYBODY have a problem with tolerances on their mains when switching to ARP studs or bolts from factory fasteners. This is with and without line boring and line honing of the block. I believe the main idea behind using the ARP stuff is the tensile strength of the fastener, not so much the clamping force. The engine manufacturer has a desired and stated figure, and no matter what brand the fastener is, it should be pretty close to the factory torque number.

If you're worried, couldn't you use some plastigage on the mains and check if the new bolts change any of your clearances?

Ok, enough "misinformation" ;)

First as Carl stated ARP implies you will always need to redo the linehone.
While I don't agree totally with this as I have not seen the majority of blocks changing & it is partly to cover there asses if things do change, the fact is in a number of cases things do change.
They would probably sell even more bolts & studs if they said nothing.
You could just buy their bolts & possibly go on your merry way.

Bob,
Just because "3 engines don't need line honing" does not mean all engines do not.
The fact is both Carl & I have done a lot of engines over the years & in his case this is one of his specialties.

I can tell you in my experience, in MOST cases changing main bolts will not change the main bore but to assume this means they will never change based on three engines is not the best logic. ;)

Steve,
With due respect to your machinists, what they said is essentially correct, they RARELY line hone because of a change in fasteners.
This to me at least, means some will change.
This does not imply you shouldn't check.
As for rods I don't care how they are located if they have a nut & bolt arrangement & you press a new bolt into the rod it will in every case need to be resized.
If it is a capscrew this does not apply.

caru68,
The strength of the fastener does indeed give you more clamping force & this can change the size & geometry of the main bores.
I don't know how many engines you do but I can tell you that on some blocks the size of the main bore & the size & geometry of the cylinder bores can & will change if you instill more clamping force in the mains.

Just for info, changing the type or length of the head fasteners or even the type of head gasket can & will sometimes change the cylinder bore geometry. This is directly related to the clamping loads of the fasteners.

With all this said, I will agree that in most cases changing from one main bolt to another is not going to change the main bore geometry but to imply this is never the case is not the best advice I have seen.
It can & does change in a number of cases, especially with studs.

This is information from more than a couple of engines in the basement, it is, from between Carl & myself probably 70+ combined years of experience.
Take it for what it is worth ;)

If you change the fasteners, at the very least you should check,,,

Mike; I agree 100% on checking, as I always have it done. I don't believe I implied that you shouldn't check the bore. Steve

For what it's worth, every motor I have ever done gets line honed, decked, honed with a plate and balanced as standard procedure regardless of what bolts / replacment parts are going in. Is it necessary, maybe not. But just like most things, the associated costs to have these operations done is virtually insignificant to the total cost of building an engine. And defintely insignificant to the cost of tearing down and rebuilding again.
Call me eccentric, as I have said this before, but I am often amazed at how many guys will cut corners on putting together a motor (mostly in the shortblock, even though they may have/could have bought quality parts or even used good reworked stock parts if that's what it takes to allow for a machining budget) then dump untold $$$$ on heads, induction, suspension parts, wheels, gizmos, gadgets and whatever. These same guys will sit there and scratch their heads when the motor vibrates, has low oil pressure, excess blow by or just plain doesn't make any power.

Originally posted by GRN69CHV:
For what it's worth, every motor I have ever done gets line honed, decked, honed with a plate and balanced as standard procedure regardless of what bolts / replacment parts are going in. Is it necessary, maybe not. But just like most things, the associated costs to have these operations done is virtually insignificant to the total cost of building an engine. And defintely insignificant to the cost of tearing down and rebuilding again.
Call me eccentric, as I have said this before, but I am often amazed at how many guys will cut corners on putting together a motor (mostly in the shortblock, even though they may have/could have bought quality parts or even used good reworked stock parts if that's what it takes to allow for a machining budget) then dump untold $$$$ on heads, induction, suspension parts, wheels, gizmos, gadgets and whatever. These same guys will sit there and scratch their heads when the motor vibrates, has low oil pressure, excess blow by or just plain doesn't make any power. Very good post buy Mike and yourself on every engine we build we sonic test, align hone, square deck, bore if needed and plate hone and in most cases we correct the lifter bores to .875 or .904 or bush back to standard and on some of our high end engines we have the fixture to blue print the cam tunnels which if any body checks the I.D. of the cam bores we have found them to be up to .004 oversize on some blocks so by going to an oversize bore and bearing we can correct back to blue print and on the Bow-tie and Dart blocks most of them are machined for roller cam bearings. By doing all this it takes all the GUESS work out. Some of the work we do is over kill to most people.

You engine building guys are definitely right, but all I was trying to say was that I personally know plenty of people that have built engines and run the ARP studs and bolt without align honing or line boring their blocks and never had a failure. I'm sure they may change the geometry of the main bores, but I just don't see it being a big enough change that it would effect the longevity of a motor (just from seeing it with my own eyes). If I were to build a high-dollar mill, I'd have it done the way you guys would, with the align honing, etc.

sorry hit the enter button before I was done.

Joe,

Is that J.Miller pricing?

caru68,

Fully understand and appreciate what you are talking about. Each owner should do what he thinks is right or can afford. But just for comparison the operations that I talked about are rather inexpensive (or at least I think so). And keep in mind, here in SE PA, things cost quite a bit more than in other parts of the country. The 4 operations break out as:

Line Hone 148.00
Deck Block 120.00
-------
268.00
I'm sorry guys, that's not a lot of money to get the block square. Especially a 30 year old seasoned block.

Hone w/ plate 96.00
Balance 150.00
-------
Total 514.00

When I checked my installed piston/deck ht. They were all dead on at .014 with a variance of about .0002. Which for the most part was a combination of rod and/or piston variance, most likely piston (used 20 year old out of the box TRW L2354-030's to be specific). That's fairly accurate. This is a very small investment for work that will yield longevity. I recently checked my cylinder pressure after the new cam install. My variance was 163 - 165 over all 8 cylinders. And for the most part the variance could be the speed of the starter depending on the level of charge as each cylinder is checked. I realize this has gotten off topic. But to me it just makes sense that if you have the motor apart and you intend to go to the trouble and expense of upgrading some parts, spend the little extra time and money and make it right.

Yes Vince, read it right off the receipt.

this is just me, but the machining and INSPECTION is the last place i want to cut costs. this is in no ways directed to the originator of this post because i understand and respect his question but i am amazed by some who have no prob spending whatever for "parts" but look to the very fundamental integrity of the entire project (precision machining) to try and shave a buck. if you are signing up for building a small or big block then this is a serious project and should be approached that way. i just think it is a really good idea to find a machine shop that you have confidence in, then discuss your objectives for your engine project with them and follow their advice on how to proceed, what to check and what to change. myself, i sent my block to the machinist with the 4 bolt caps and arp studs that i was going to use so he had them when he did the align hone. if i had gotten it back with something different then we would have had a conversation about that. like i said this is just my 2 cents.

Thanks for all the replies.

I had bought the ARP main bolts and told him I had them but he didn't say when he wanted them. Part of the problem was I was working with him over the phone a few hours away (I'm at school while I was organizing this, my dad was kind of being a gofor bringing parts to him). The main thing was he was not supposed to put the shortblock together, as I was going to do it, but he decided to do it no charge just to 'make sure it was right' and I guess decided to do it without.

Sorry to misinform anyone, I just didn't see a change in the mainbores when I switched to ARP. My machinist didn't see any either on the last one. Definately they all should be checked and align honed if needed- for sure, I agree. I just don't think it's a 100% given that they will change. Some budgets are much tighter than others and will greatly influence decisions made during a build. Bob

As a performance engine builder for 28 years now we have seen over the years customers bring there blocks and bearing in that they just have taken out and you can see signs of bearings with horrible wear patterns in them.

We ship blocks all over the country and we can't take any chances on guess work. ARP is a big company and I don't think I would try too second guess them as I find there info very credible.

I Don't now of any HIGH PERFORMANCE MACHINE SHOPS that don't line hone there blocks as a starting point. Most people that argue this point don't have the equipment to line hone a block, Of coarse there going to say its fine as we have seen the results of this many times. As on a SBC or BBC the bore tolerance from low to high is .001 as long as its in that spec they call it fine, We work in .0001 at our shop.

GRN69CHV, You can add about 50% to the prices of machine work you stated up here in New England (Massachusetts and Rhode Island, anyway). I had a 402 bored and honed a few years ago, and was never asked about align honing it. Maybe I should ask my machine shop about that one. I've never had a problem with any work he's done for me, but I'd like to know where he stands on this. He builds motors for a few guys that run cirle track at Thompson Speedway in CT, so he's a reputable shop.

Mind you, that was in Sept-Oct of '93. Sure he has went up since then (everything else has). Even so if the tab is now 350.00 for line bore and decking, it is still a small piece of the puzzle in relation to the total $$ spent.

Originally posted by CNC BLOCKS N/E:
As on a SBC or BBC the bore tolerance from low to high is .001 as long as its in that spec they call it fine, We work in .0001 at our shop. Carl, are you saying that if the main bores are within .001" out of round, then this is acceptable? This is the spec that I have gone by.
I checked a friend's mains on a 454 after an align-bore and it was .0035" out of round with or without the bearings. Way too much egg shape for me. Clearance ended up about .0025" to .0055" and he had almost no oil pressure.

Originally posted by Wooderson:
</font><blockquote>quote:</font><hr />Originally posted by CNC BLOCKS N/E:
As on a SBC or BBC the bore tolerance from low to high is .001 as long as its in that spec they call it fine, We work in .0001 at our shop. Carl, are you saying that if the main bores are within .001" out of round, then this is acceptable? This is the spec that I have gone by.
I checked a friend's mains on a 454 after an align-bore and it was .0035" out of round with or without the bearings. Way too much egg shape for me. Clearance ended up about .0025" to .0055" and he had almost no oil pressure. </font>[/QUOTE]In all the years I have been building engines I have never seen a main bering bore .0035 out of round and after looking at your profile and seeing that your occupation is watching HEE HAW after reading that its hard to beleive.

But we have seen blocks that have come from the factory with the main line over size up to .0015 and when we are done line honing they are .0015 bigger at the parting line and never has hurt anything as you would have more eccentricity in your bearings and some bearing companys have more eccentricity then others.

Take a stock block torque the caps run the line hone through for a couple of strokes and then look and see how things look I'm sure that will change your out look on how things are done. We line hone Brand new blocks as once the caps are taken off and retorqued they seem too change from what they originaly were. When we line hone always loosen the caps and retorque to see if they repeat.

Originally posted by caru68:
GRN69CHV, You can add about 50% to the prices of machine work you stated up here in New England (Massachusetts and Rhode Island, anyway). I had a 402 bored and honed a few years ago, and was never asked about align honing it. Maybe I should ask my machine shop about that one. I've never had a problem with any work he's done for me, but I'd like to know where he stands on this. He builds motors for a few guys that run cirle track at Thompson Speedway in CT, so he's a reputable shop. Afew years ago Tom Vigue and I were doing engines for Ricky Martin who ran Thompson and Seekonk speedway and had a few championships with our engines and all those engines we did for Ricky were line honed as they had splayed caps on them.

Originally posted by CNC BLOCKS N/E:
[/qb]In all the years I have been building engines I have never seen a main bering bore .0035 out of round and after looking at your profile and seeing that your occupation is watching HEE HAW after reading that its hard to beleive.


Carl, The Hee Haw thing is called humor smile.gif I get bored with life sometimes and try to put a little fun back into the world. That WAS a serious question on the egg shape condition. I've been a machinist for eight years now and on occasion someone will want me to measure something for them (I own my own bore gages).

The block that was out .0035" was NOT done by me or where I work ( it was done by "big time hi perf spend lots of money on advertising machine shop" near where I live), but in the past when I brought this example up on this very forum someone said they wouldn't have a problem with it - I completely disagree. I was just wondering in your experienced opinion what you allow since I don't align-bore blocks ( I have a trusted shop do this for me). The one 454 with a factory align bore that I have was within .0008" out of round so I figured .001" or less was good.

Edit: Thanks for the reply Carl, and try to smile once in a while smile.gif

whoops

The block that was out .0035" was NOT done by me or where I work ( it was done by "big time hi perf spend lots of money on advertising machine shop" near where I live), but in the past when I brought this example up on this very forum someone said they wouldn't have a problem with it - I completely disagree. I was just wondering in your experienced opinion what you allow since I don't align-bore blocks ( I have a trusted shop do this for me). The one 454 with a factory align bore that I have was within .0008" out of round so I figured .001" or less was good.

Edit: Thanks for the reply Carl, and try to smile once in a while smile.gif [/QB][/QUOTE]

I recall a couple of old Wiston cup blocks that came in the shop for some work and we found that the main bores were big at the parting line and this was done on purpose to put more eccentricity into the bearing as I spoke of before. What they did was line hone it oversize and recut the caps and line hone it again to the get there vertical demension they wanted. smile.gif