help identifying new rod bolts

[TX]

I was hoping someone in the know could help me identify these rod bolts I purchased.
They are supposedly BE ARP S65 bolts "BE-CRB50-S65" but I do not have any indication of what I was shipped. They just arrived in a bag without any part number or packaging. The heads are stamped ARP 2000 -31. Are these the BE spec ARP bolts or the regular ARP 2000 bolts (non-BE spec)?
Photos below:

[Blindside_137]

Where did you order from?

I got mine from Mpower motorsports. I agree it is confusing. But when I look at other sellers online it mentions them being ARP 2000.

See auto talent listing. https://autotalent.com/products/be-a...2-m3-2008-2013

[Helmsman]

Believe the BE bolts are resell of ARP-2000: http://wiki.rcollins.org/core/index..../S85_Rod_Bolts

[Blindside_137]

Here are mine

Maybe deansbimmer can chime in as well

[TX]

Originally Posted by Helmsman

Believe the BE bolts are resell of ARP-2000: http://wiki.rcollins.org/core/index..../S85_Rod_Bolts

Good evening Sir,
I'm sorry for the late reply and thank you for the link.
With your link, it looks like these could be VAC or BE (ARP2000) bolts with different specs and no way of really knowing. I suspect the -31 is the clue. I was hoping someone from BE (autotalent) could chime in here on the topic or deans as he has done a fair share of bearing installs.
That article has the bolts being designed differently between VAC or BE with different torque specs. I'd really like to know which I was sold.
Cheers,
X

[pbonsalb]

It’s the same material so it should not matter. I read a rumor years ago the the VAC ARP 2000s are actually an existing bolt from another application. I don’t know which but 350z or 370z pops into my head - but it could be popping into my head for an unrelated reason.

[Blindside_137]

Welp. I panic bought a set from turner motorsports. They listed them as in stock and 2 day shipping on them wasn't terrible.

Hoping they still make it in time for my service next week. Should be able to compare with the ones from M power and perhaps both are BE spec.

[Helmsman]

Originally Posted by TX

Good evening Sir,
I'm sorry for the late reply and thank you for the link.
With your link, it looks like these could be VAC or BE (ARP2000) bolts with different specs and no way of really knowing. I suspect the -31 is the clue. I was hoping someone from BE (autotalent) could chime in here on the topic or deans as he has done a fair share of bearing installs.
That article has the bolts being designed differently between VAC or BE with different torque specs. I'd really like to know which I was sold.
Cheers,
X

Not convinced BE managed ARP to make a custom design for peanut volumes, even if BE charge good money for it. Believe its ARP-2000 standard.
What ever ARP rod bolt for the S65 will work fine in my book.
Ps. ARP-625 is what ARP recommend them self for the S65. Would have been very expensive after BEs add though.

[pbonsalb]

And ARP 625 is totally unnecessary for the S65, which has no need for stronger rod bolts. I can’t recall reading of a stock bolt breaking, even on a supercharged motor. The main advantage of ARP is convenience when installing. They are also reuseable, but few plan to install a third set of rod bearings. 2000 is good enough and cheaper.

[GORDON.M3]

ARP2000 is perfectly fine. Make sure the wrench is calibrated and correct. Apply the grease that ARP supplies with their bolts correctly and you won't have a problem. AGE625s for the S65 are overkill.

[TX]

wasn't the reason against the 625's is that the clamping force was too high and they caused bore distortion?

[Helmsman]

Originally Posted by TX

wasn't the reason against the 625's is that the clamping force was too high and they caused bore distortion?

According to BE's measurements yes. ARP says differently though. God knows.

[deansbimmer]

They look like BE to me.

The latest batch of ARP bolts shipping from BE fit a 3/8" socket and are engraved with BE ARP2000 on the head. They're not repurposed from a different application.

[deansbimmer]

Originally Posted by TX

wasn't the reason against the 625's is that the clamping force was too high and they caused bore distortion?

We've had great success with the 625. Aside from being massive overkill for the application I'd imagine the biggest reason for using the 2000's is that they cost significantly less.

[Blindside_137]

Rod bolts are confirmed different.

I received my set from turner. The packaging and inside label clearly identifies them as BE spec. The head also states "BE" instead of the "31"

Visually they have a few subtle differences as well, shorter thread on the BE. Last photo has the -31 version on left and the BE spec on right.

[pbonsalb]

I wonder what the -31 application was originally for?

[TX]

Those bolts are completely different in your picture. This is rather unnerving.

[pbonsalb]

I am not sure it is unnerving, just not as perfect.

[TX]

I wonder if perhaps there was a design revision by ARP somewhere along the line that accounts for the differences?

[m235boy]

So those that received the arp 2000 - 31 what is the torque to be applied? Same as the be ones?? I received a set but no instructions in the box.

[Blindside_137]

Originally Posted by m235boy

So those that received the arp 2000 - 31 what is the torque to be applied? Same as the be ones?? I received a set but no instructions in the box.

From my understanding the ARP 2000 is 50 ft lbs regardless of being BE spec or not.

[frankc]

Originally Posted by Helmsman

Believe the BE bolts are resell of ARP-2000: http://wiki.rcollins.org/core/index..../S85_Rod_Bolts

Interestingly, the site linked above states:

SPEC: ARP-2000: Torque Procedure
45 ft-lbs (VAC).
50 ft-lbs (BE-ARP).

Did the BE ARP bolts always have the "BE" stamped on them (instead of a number), or is this something recent? If recent, the how does one know if they have "BE" spec bolts or something else, and subsequently which torque spec to use?