Main studs; I should have asked the Speedtalk community first...

[70MC]

15 years ago I was rebuilding a Jeep engine that needed new head bolts, I couldn't believe the price Mopar wanted for one bolt so I called ARP to see how much they wanted for a set. They did not have a set for a Jeep, but with my info on what I needed, the put a set of together and sent them to me at a very fair price.
Call ARP and they will sell you what you need.

[cjperformance]

Arp ARP154-5503 is for 351w 2 bolt main, 1/2" stud with a smaller thread on 6 of the studs to attach a windgae tray etc. But it depends wether you mean SBF as in 302 or 351 ?

[Caprimaniac]

Arp ARP154-5503 is for 351w 2 bolt main, 1/2" stud with a smaller thread on 6 of the studs to attach a windgae tray etc. But it depends wether you mean SBF as in 302 or 351 ?

So, are you saying 351W are 1/2" ? If so, how could I have missed that? No excuse for that. But then, a set for 2- bolt for windage tray is probably what I could use. This is for a 4- bolt 302. ManoWar World- Block. Probably Dart Blocks have 2" mains as well?

If you compare length of Stock 2- baolt mains 302/352 W- are length of bolts the same? If so, comparing required stud length With a Stock 2- bolt 302 would give me a Clue.

[Dave Koehler]

I see some parts listed but no studs on this link.
Why not contact them and get this question narrowed real quick.
There is also the ARP catalog I referenced earlier.
https://www.billmitchellproducts.com/wo ... ular-caps/

[cjperformance]

Arp ARP154-5503 is for 351w 2 bolt main, 1/2" stud with a smaller thread on 6 of the studs to attach a windgae tray etc. But it depends wether you mean SBF as in 302 or 351 ?

So, are you saying 351W are 1/2" ? If so, how could I have missed that? No excuse for that. But then, a set for 2- bolt for windage tray is probably what I could use. This is for a 4- bolt 302. ManoWar World- Block. Probably Dart Blocks have 2" mains as well?

If you compare length of Stock 2- baolt mains 302/352 W- are length of bolts the same? If so, comparing required stud length With a Stock 2- bolt 302 would give me a Clue.

Yes, 351 W and C are 1/2".
Stock block and caps 302 W bolt length measured from under the head is 3.16"
For a 351 W is 3.5"
For 351 C is 3.26"

[Caprimaniac]

CJ; Thank you, data of importance.....

UHL of studs are a bit longer than on the 351w: 3.66". However, there's always some threads x- tra on these studs. A kit for the 351w sounds promising.


I have read the rest of you correct; by machining threads in these (Cold- rolled and hardened (actually the the marketing say they are hardened before they are rolled, , oxide finnish) studs will make them unuseable? Pretty much ruin them?

[Zmechanic]

CJ; Thank you, data of importance.....

UHL of studs are a bit longer than on the 351w: 3.66". However, there's always some threads x- tra on these studs. A kit for the 351w sounds promising.


I have read the rest of you correct; by machining threads in these (Cold- rolled and hardened (actually the the marketing say they are hardened before they are rolled, , oxide finnish) studs will make them unuseable? Pretty much ruin them?

IF you can even get them to cut well (might be able to with carbide), you still wouldn't know what the thread profile looks like that was originally rolled in (especially the root). You're almost guaranteed to significantly weaken the stud at the root of the threads by trying to cut extra threads in. I'd shim, shorten or get custom.

[Schurkey]

The instant you begin cutting threads, you disrupt the grain of the metal and create stress-risers.

Cut threads can be geometrically perfect, but they're still weaker than rolled threads because of the interruption of the metal grain; and the fact that the compressive forces of thread rolling impart a work-hardening effect that cutting doesn't.

[cjperformance]

^^^ exactly, DO NOT recut these or any rolled thread.

[Momus]

The instant you begin cutting threads, you disrupt the grain of the metal and create stress-risers.

Cut threads can be geometrically perfect, but they're still weaker than rolled threads because of the interruption of the metal grain; and the fact that the compressive forces of thread rolling impart a work-hardening effect that cutting doesn't.

So the theory of rolled versus cut thread goes. For many applications a properly designed waisted stud with machined threads will spread the loads and avoid a stress concentration and give perfectly good service.
A lot of main and head studs also commit the crime of having a fine and a coarse threaded end- tension area is obviously greater at the fine end and the greater thread root radius of the coarse inserted end will not balance. There does not appear to be a problem of insufficient stretch or over tensioning with these.

For a long time we were told that forged crankshafts, non twist, were the pinnacle of design. Now it is well understood that cranks machined from almost zero anistropic super clean bar steel are superior. I would not get too carried away with the rolled versus CNC machined thread in clean steel arguments.

[Caprimaniac]

I see some parts listed but no studs on this link.
Why not contact them and get this question narrowed real quick.
There is also the ARP catalog I referenced earlier.
https://www.billmitchellproducts.com/wo ... ular-caps/

Ya, Dave! I followed Your suggestion here. Looked at Bill Mitchell's site this morning but no mention of studs for windage trays. So, I wrote them a Message.

They got back to me real quick and it turns out they have the correct studs w/ provision for windage tray in Stock at a very reasonable price. Hopefully they can ship it over here for a reasonable amount, too,

What I can learn from this is: Don't stress, don't hurry; take Your time getting the right parts instead of pushing the "Add to cart"- button when you THINK parts might fit and THINK you can save some $..... Never again, or?

[Caprimaniac]

Well- it did not end well…. Something like " Oh… after all, it wasn't the right size studs"....

Seems like the only option is to call ARP. It would be stupid to "guess" one more time.

[pdq67]

Does Chevy still use 300M head-bolts?

I figure a 300M bolt is about the BEST there is for bolts. Either it or 1045 OQT for bolt use.

pdq67

[Valve seat 1]

ARP studs are heat treated. But not to a high standard maybe 32 Rockwell C scale . Which is plenty machinable they can’t be to hard because they have to be able to stretch. The threads are rolled which makes the molecules of the metal more uniform

[Schurkey]

Does Chevy still use 300M head-bolts?

I figure a 300M bolt is about the BEST there is for bolts.

My ancient GM "Standard" parts catalog--nuts, bolts, clips, wire connectors, all the piddly crap that any of the GM divisions might use--does indeed show "300M" as a "Grade 8" bolt spec., although as I said, the catalog is decades old.

Keep in mind that while the grade of steel is important, so is heat-treat and other material processing. There's no description of how GM heat-treats the bolts; or whether the threads are rolled before or after heat-treat. The OEM bolts are good, no doubt. Whether they compare to ARP is another matter.