Main Studs??

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nasty68

nasty68

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When going from bolts to studs in the main's, is it necessary to have the main's align honed?
 
Crap....I have been running my 440 for over 20 years with studs and didn't have the mains aligned when I changed.

I am not sure why it would be necessary. I don't believe changing to studs would affect how the main cap fits in the saddle of the block. But I am not an engine guru.
 
Have it honed. It's the correct way. will it run without it, likely. But it could distort a bearing saddle slightly causing a main bearing failure.
 
rklein383 said:
Crap....I have been running my 440 for over 20 years with studs and didn't have the mains aligned when I changed.

I am not sure why it would be necessary. I don't believe changing to studs would affect how the main cap fits in the saddle of the block. But I am not an engine guru.
Click to expand...
Wow me too and about 4 buddys changed and never had issues in past 20 yrs...pray tell me how it would affect the caps/main/brgs.if they were the same ones that came off engine and same sequence other than stud is no doubt stronger than bolt and that may be debatable..
 
Not saying it is the same in every case or engine block, but I put studs in my block and did not have to hone it. Torqued caps down and slid a go no/go bar in through the saddles. Went in just fine no distortion noted....
 
I have done many through the years and not even worried about it.
 
RustyRatRod said:
I have done many through the years and not even worried about it.
Click to expand...

yep what he said! done it plenty no problem. the only time I had to have one line hone was one that the saddles in the block were off. you would set the crank in the block and it wouldn't turn without the caps being on it.
I didn't take that block apart before it went in fro machining but my guess is those bearings and crank didn't look so hot.
 
They will be fine just putting in the studs and not realign boring. The bolts/studs do not locate the main bearing cap like the rod caps do.
 
I am with Kim here...ALIGN HONE IT !
When switching from Main Cap "Bolts", to Studs, it is highly adviseable to have the Bores checked with a Dial Bore Gauge at the very least....the Default being to Align Hone the mains as best practise.
THINGS HAVE CHANGED !
** Years back the recommended Torque for ARP Studs was 80 ft/lbs with their Moly, and 110 Ft/lbs with Oil...and usually Guys were using "P" eccentricity Main Bearings back in the Day as well, more forgiving clearance-wise as you move away from the parting lines, so no wonder many ran just fine as very forgiving to Main Bore distortions created by the Studs.
Nowadays,
the newer ARP Moly recommends 110 Ft/Lbs, and a lot of guys are using "H" Mains for the higher filet Cranks etc., so the distortion and "forgiving" factors have gone up proportionally IMO.
Personally, I haven't seen too many recently, that when the Studs are substituted, don't have at least one or two Caps that go "tight" past my comfort zone for performance useage, and require at least some Align Hone work, which, I usually just cut all 5 Caps and do it right because I gotta Dyno it before it leaves with my name on it.
That said,
as the saying goes....yep, SH*T will run...you do as you please......but don't think the Bores aren't distorted.
 
Here's what I think. If the bores are fine with bolts, there will be no change with studs. Having worked in a machine shop for a good many years, I have measured before and after. I think it's certainly best to have it checked at the least, because if you are making the change to studs, chances are you have the engine apart anyway.
 
The align honing I thick is a personal preference. The only differences between a bolt and stud are the forces applied to the fastener which could or could not cause failure depending on application.
A bolt has two different forces in which it is used, one is a rotational force since you a screwing it into a thread, and the other is a clamping force or holding force to what ever it is securing
A stud only has one force applied to it when tightened and that is clamping or holding force.
So if you clamping with a stud it should not distort unless you do not torque it properly.
Also here is a little read that my be helpful also.
Engine studs: Understanding the advantages of using studs vs. bolts, and tips on achieving proper clamping loads - Automotive Service Professional
http://www.autoserviceprofessional....dvantages-of-using-studs-vs-bolts-and-tips-on

May I add also GOOGLE, YAHOO, and other search engines can be very informative if the right key words are applied
 
Thanks for the replies. A few different thoughts on this topic. The motor is not apart yet, it's down to the short block at the moment but it will be coming apart. At the very least it will go to the machine shop to get cleaned. At most it will get cleaned, decked and honed. Either way i will get the studs and have them in before it goes to the shop.
 
My take on it is simple. If a mild motor is together you wouldn't bother to put studs in it, but if you're building a motor where studs are considered necessary the engine should be blueprinted and that should include the main bearing bores...
 
Yes, have it line honed. Also check the clearance between the stud and the holes on the cap as bolts are relieved and studs aren't, and it will often interfere and bind, causing distortion.
 
Jim Lusk said:
My take on it is simple. If a mild motor is together you wouldn't bother to put studs in it, but if you're building a motor where studs are considered necessary the engine should be blueprinted and that should include the main bearing bores...
Click to expand...

The best response on the thread. ^^^^^
 
Just cause you have switched and got away with it doesn't mean that is the final answer. When you add studs to the mains why not have it checked after torquing the mains. Cheap insurance I'd say.
 
SGBARRACUDA said:
Just cause you have switched and got away with it doesn't mean that is the final answer. When you add studs to the mains why not have it checked after torquing the mains. Cheap insurance I'd say.
Click to expand...

Of course, you still have to check clearances, and for distortion.

On the numbers, 9 out 10 blocks will 'not' be affected.
 
I have been Machining and building 440's for going on 40 years, I OWN an Align BORING jig, as well as an Align Honing Cabinet CH100 Sunnen.

Aside from anyone getting "lucky" as Mains are pretty forgiving....

I have never seen a Main Bearing Cap that does NOT distort beyond my comfort level....
when switching from stock Main Bolts @ 80 Ft/Lb Torque with stock BOLTS...
to
ARP Studs with 110 Ft/Lb Torque using ARP Moly
In my experience, They ALL DISTORT in the above scenario !

You think it's "OK" , by all means you screw it together.
 
Interesting…. I have always had it done when building an engine with studs.

But I just may be calling BS on this line hone crap too! Just like my 600HP SBM block limit thread here…… http://www.forabodiesonly.com/mopar/showthread.php?t=165579&highlight=600hp+limit

I have been smacking my 500+HP NA SB for a bit now with a 150 Shot. I will be creeping my way most likely into the 350+ Shot range here in the near future too. I will at some point find its limit….no worries I am already in the process of building the next one! Lol
 
I remember when I was younger, and had a lot more fun with cars, we used to throw stupid stuff together. We built a 307 chevy (I know LOL!) that was thrown together, stock cast pistons, double hump heads, 2.02 1.60 valves, home ported, We threw arp rod bolts in the stock rods, no machining, arp main bolts, again no machine work, and a comp 270h. I have no Idea how that engine held together, or even ran. was in a 65 cj5. with 4.27 gears and the stock 3spd trans. Thing was pretty dang quick, won a lot of street races (don't do it anymore!). That thing regularly hit 6500 rpm with a couple missed shifts hit 7000+! Anyways I grew up and learned better, But unfortunately, it costs me a lot more $$$ to build engine now. But for some reason I just have this urge to build a JY engine, on the cheap, say screw the rules lets see what happens!
 
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