IE Rod bolts (ARP 2000) torque spec - 26ft-lbs or 50ft-lbs??

[97B518TQM]

So I was installing the new rods with pistons in my block today and did a few searches for torque specs on the APR bolts that come with the IE rods. I know what the Bentley manual says but I am assuming that spec is for OEM rod bolts so I wanted to double check if that spec also applies to the ARP bolts. In several places I found a spec of 50ft-lbs but some places specified 26 or 28 ft-lbs of torque. Pretty much all versions instructed to do it three times to the same torque spec. The problem is the different torque numbers different places specify. Someone also asked the same question on IE's facebook page and they responded with "two cycles to 50 ft-lbs and the third cycle to 55. So I decided to follow that and guess what? Two of my bolts overstretched and actually tore in two pieces. Even though the other bolts didn't break/tear I am afraid that they are overstretched and way too thin. I ordered 12 new ARP bolts from IE and I am guessing the 26ft-lbs spec is the right one given the results I've see with the 50ft-lbs spec. 26 just felt way too little but it's a fairly fine pitch so I guess it makes sense. What has everyone used so far?

[itguy]

the 50ft/lbs is for the size up. The 5/16th bolts which are used in our rods should be 28ft/lbs. I personally did mine to 35ft/lbs with good loctite. RTL5009 had his come loose on him when tq'd to 28. 100's of people have sued 28 without issue though so anything over 28 and you are fine.

[97B518TQM]

the 50ft/lbs is for the size up. The 5/16th bolts which are used in our rods should be 28ft/lbs. I personally did mine to 35ft/lbs with good loctite. RTL5009 had his come loose on him when tq'd to 28. 100's of people have sued 28 without issue though so anything over 28 and you are fine.

Ok, that's excellent info. I guess I really overstretched them then. You mentioned loctite. You used loctite instead of the ARP lubricant?

[SpeedWorksAuto]

I just had the same issues and I think I figured out the difference. The 50# torque spec was for the studs/cap nut type setup that IE comes with, and the 26# (I found 28#) is for the actual ARP 3/8 bolts. I beat myself up over it for a few days refusing to bolt the pans on until I had I knew for sure. I am using the bolts so I ran mine up to 28#.

[97B518TQM]

I just had the same issues and I think I figured out the difference. The 50# torque spec was for the studs/cap nut type setup that IE comes with, and the 26# (I found 28#) is for the actual ARP 3/8 bolts. I beat myself up over it for a few days refusing to bolt the pans on until I had I knew for sure. I am using the bolts so I ran mine up to 28#.

Be very glad you didn't torque to 50. The bolts get very stretched and if they don't break I am sure they are very weak and will break very very soon after you start the car.

[jibberjive]

I just had the same issues and I think I figured out the difference. The 50# torque spec was for the studs/cap nut type setup that IE comes with, and the 26# (I found 28#) is for the actual ARP 3/8 bolts. I beat myself up over it for a few days refusing to bolt the pans on until I had I knew for sure. I am using the bolts so I ran mine up to 28#.

The IE rods for the 2.7t don't come with 3/8" bolts, they come with 5/16". And the torque spec straight out of the ARP literature that I saw was 26ft/lbs (for the 5/16").

[Monty23]

I torqued my bolts to 26 ft-lbs... You should torque them down so that you get proper radial bearing clearance (plastigauge)....

[rtl5009]

I torqued my bolts to 26 ft-lbs... You should torque them down so that you get proper radial bearing clearance (plastigauge)....

I torqued mine to 26 first time around, 3 times with lube. Clearance checked out.

Started the fu*ker up, let it warm up- changed the oil. Everything was kosher. Second start- rap, rap, rap, rap....... #1 rod cap drivers side bolt came a little loose some how.

Pulled the motor, re-re-built the bottom end, bumped my rod torque to 28 ftlbs, clearances were fine.

Definitely do not torque them to 50 ftlbs

[Monty23]

I would have been pissed...

[rtl5009]

I would have been pissed...

oh I was..... At least it did it second start at idle and not first pull.....

It started knocking and I was like fock, put my ear to the pan

Nothing was fucked, not even the bearing on that cap, I just took it apart and back together it. I enjoy building the actual motor, its the motor in/out that is the hassle.

[Monty23]

Yes, and gluing the damn pans on...how many miles are on you're built bottom end now?

[rtl5009]

7 thousand and some change

[julex]

"with good loctite"

WHAT?

Rod bolts need to be dunked in moly lube and torqued to specs. If you use loctite then your bolts are undertorqued and will allow the rod ends to cyclically separate and eventually fail...


Anyway, you torque the bolts with STRETCH GAUGE on the bolt to attain required stretch of the bolt, not torque. So it happens that on average the bolt needs to be torqued down at a given lb/ft with lube on threads to get into the ballpark of stretch but I've seen my own bolts going in with about 4lb/ft spread on torque value to get to proper stretch.

[rtl5009]

WHAT?

Rod bolts need to be dunked in moly lube and torqued to specs. If you use loctite then your bolts are undertorqued and will allow the rod ends to cyclically separate and eventually fail...


Anyway, you torque the bolts with STRETCH GAUGE on the bolt to attain required stretch of the bolt, not torque. So it happens that on average the bolt needs to be torqued down at a given lb/ft with lube on threads to get into the ballpark of stretch but I've seen my own bolts going in with about 4lb/ft spread on torque value to get to proper stretch.

This is a stretch gauge for rod bolts if anyone is wondering:

http://www.summitracing.com/parts/su...FdKj4AodU0oAEw

You can get away with a good calibrated torque wrench. Use a stretch gauge if you want to be right on the money with the spec given by ARP, julex is correct that the torque is a round about way of saying the bolt has stretched X amount, but not a guarantee .

[SpeedWorksAuto]

The IE rods for the 2.7t don't come with 3/8" bolts, they come with 5/16". And the torque spec straight out of the ARP literature that I saw was 26ft/lbs (for the 5/16").

You are right, I think it a 3/8 head on the bolts. I got it mixed up. ARP literature says 26#, we ordered the "special" bolts that a name brand rod bolt company suggested and they spec'd 28#. It just so happens they cross reference to the same ole off the shelf ARP's. My friend has been using these bolts for years and torques them to the rod company's specs. All clearances were checked and was spot on at 28#.

[julex]

This is a stretch gauge for rod bolts if anyone is wondering:

http://www.summitracing.com/parts/su...FdKj4AodU0oAEw

You can get away with a good calibrated torque wrench. Use a stretch gauge if you want to be right on the money with the spec given by ARP, julex is correct that the torque is a round about way of saying the bolt has stretched X amount, but not a guarantee .

Key here is that if using torque wrench, one must absolutely use moly lube on threads and under the cap of bolt so that the amount of thread/head friction is controlled and resulting bolt stretch predictable... somebody above here using loctite on bolt threads is just insane (nothing personal) and might be a reason for engine failure.

[rtl5009]

Key here is that if using torque wrench, one must absolutely use moly lube on threads and under the cap of bolt so that the amount of thread/head friction is controlled and resulting bolt stretch predictable... somebody above here using loctite on bolt threads is just insane (nothing personal) and might be a reason for engine failure.

didn't say otherwise, I used lube on mine. Copious amounts of lube.

[B5Ballin]

I used lube on mine. Copious amounts of lube.

Giggity...

[aysix]

Torqued mine to 30 ft-lbs, all clearances in spec.

[jibberjive]

Yeah, moly lube is absolutely critical. ARP supplies a packet with each set of bolts.

[itguy]

Yeah, moly lube is absolutely critical. ARP supplies a packet with each set of bolts.

I used the included lube to run in and out twice. 3rd time, cleaned all lube from threads and used red loctite, rtl5009 story scared me into it

[julex]

I used the included lube to run in and out twice. 3rd time, cleaned all lube from threads and used red loctite, rtl5009 story scared me into it

Well, do you understand that by doing that you removed lubrication from threads that ensures the bolts are consistently stretched properly when used with torque wrench torque down method? More critically, by removing the lubrication and still using torque specs for lubricated threads, you effectively prevented yourself from developing proper stretch of a bolt which ultimately is the force that holds parts together.

The net effect is that instead of 1000lb (pulling the number out of thin air for illustration purposes) of force the stretch would apply to parts when torqued down to 28# with lubrication, your loctited threads that gave far more resistance to torque force caused your bolt to stop stretching far short from proper value and now your stretch is developing 500lb of force perhaps allowing the parts to cyclincally separate and material fatigue is working its magic there...

[SpeedWorksAuto]

So I was installing the new rods with pistons in my block today and did a few searches for torque specs on the APR bolts that come with the IE rods. I know what the Bentley manual says but I am assuming that spec is for OEM rod bolts so I wanted to double check if that spec also applies to the ARP bolts. In several places I found a spec of 50ft-lbs but some places specified 26 or 28 ft-lbs of torque. Pretty much all versions instructed to do it three times to the same torque spec. The problem is the different torque numbers different places specify. Someone also asked the same question on IE's facebook page and they responded with "two cycles to 50 ft-lbs and the third cycle to 55. So I decided to follow that and guess what? Two of my bolts overstretched and actually tore in two pieces. Even though the other bolts didn't break/tear I am afraid that they are overstretched and way too thin. I ordered 12 new ARP bolts from IE and I am guessing the 26ft-lbs spec is the right one given the results I've see with the 50ft-lbs spec. 26 just felt way too little but it's a fairly fine pitch so I guess it makes sense. What has everyone used so far?

I used this fro my specs. Sorry I posted wrong info. I used 28# for my 5/16, and the 50# was for the larger bolts that IE uses on their 1.8t rods.

[04/01-s4]

Hate to bring this up from the dead but MAN am I happy I found this discussion. I just put my short block together this weekend including the upper oil pan. I torqued the arp-2000 bolts to 30 ft lbs because of this,

http://beta.arp-bolts.com/kits/ARPki...?RecordID=1202

click on kit instructions and you'll see ARP recommends 30 ftlbs, so that's what I did using their supplied lube.

The problem was just today I came across a few conflicting threads with people talking about 50-55 ftlbs, being frustrated I had plans on tearing the pan/oil tubes off tomorrow and re-torquing to 50 ftlbs, GLAD I didn't and I can continue putting her back together as planned. Going to sleep easy now.

Btw if anyone was wondering I also installed the ARP main stud kit using the 3 step method in sequence of 30NM,60NM and 90 degrees which dialed out to just over/under 100 ftlbs each time. (ARP recommends this off of their own site as well)

OEM connecting rod cap install specs (30 Nm + 90 (1/4 turn) This is 2.8 motors? I thought we had the same rods?

Interesting, though much of this is 2.8
http://www.dj-sures.com/GraphicFiles...20assembly.pdf

teaser

[julex]

People, get a f.ing stretch gauge and stop this talk about ft/lb.

Torque to stretch, which is the way all bolts/studs are specced to the fastened with, not to ft/lb which is just an approximation of how many ft/lb it takes to reach desired stretch given a certain condition of bolt and threads. Any variation in lube, temps, etc will alter the stretch if you're going by ft/lb.

With a stretch gauge, you fasten the bolt until it reaches the stretch you need and that's it. Small investment to ensure rods doesn't snap or unfasten itself in critical place.

[uponone nogaro]

I will be building a block soon this thread Will help with the tq specs on the rod bolts

[jibberjive]

I have changed the recommended IE torque spec on my engine build sheet from 26 ft/lb to 30 ft/lb based on my updated research, from this post:

http://www.audizine.com/forum/showth...1#post11720966

[vavJETTAw36]

I think we need a sticky thread just for torque specs. From oem to aftermarket.


Sent from my iPhone using Tapatalk

[Mark00s4]

People, get a f.ing stretch gauge and stop this talk about ft/lb.

Torque to stretch, which is the way all bolts/studs are specced to the fastened with, not to ft/lb which is just an approximation of how many ft/lb it takes to reach desired stretch given a certain condition of bolt and threads. Any variation in lube, temps, etc will alter the stretch if you're going by ft/lb.

With a stretch gauge, you fasten the bolt until it reaches the stretch you need and that's it. Small investment to ensure rods doesn't snap or unfasten itself in critical place.

cheap insurance for sure!! for knowing that your rods bolts are torqued correctly.

[RC200]

Audi aftermarket conrods use ARP2000 bolts 5/16 with 1.5" length.
The torque is 30 ft.lbs / 41Nm for bolts corretly lubrificated (threads and head too !):
https://arp-bolts.com/kits/arpkit-de...p?RecordID=797

OEM conrod torque asks for 30 Nm +90°.

I'm pretty sure the additional 90° requires more than 11Nm on top of 30Nm to get achieved.

[RC200]

I finally bolted them to 35 ft lbs, 48Nm, it corresponds to 30Nm+25°

[armageddon-]

You should torque them to strech, if using NM arp recommend torquing them 3 times before final torque.

[RC200]

I torqued them this way with a torque dial wrench (no stretch gauge ...) and a light coat of bearing grease on the threads (no ARP lube):
1) all by hand
2) all 10Nm
3) all 20nm
4) all 30Nm
5) loosing everything
6) all 30Nm
7) all 41Nm
8) all 48 Nm to be sure

[Silverex]

Why bearing grease and not ARP lube? Using a different lubricant affects the TQ/stretch specs. Did you check the bearing specs with them TQ to 48nm, cause it will affect the clearances.

Like mentioned a stretch gauge is really the way to go and they only cost $100.

[RC200]

I assume the clearances are fine:
The forged conrods have OEM specs (57,600 mm), the bearings are STD, the crankshaft is OEM ...

At the moment, I have all the bottom end done, incl. the oil pump chain and the crankshaft requires 14Nm to start to be turned and 10Nm to go on.

[Silverex]

I assume the clearances are fine:
The forged conrods have OEM specs (57,600 mm), the bearings are STD, the crankshaft is OEM ...

At the moment, I have all the bottom end done, incl. the oil pump chain and the crankshaft requires 14Nm to start to be turned and 10Nm to go on.

You’re using arp rod bolts on stock rods with higher than recommended TQ spec (with different lube) and are assuming clearance is fine? That seems like a very bad idea to me. I’ve ran ARPs on stock rods (on different platforms) and always needed to get the rods resized since the added clamping distorts the rods differently than stock bolt. While you might be fine that definitely not the way I’d go about. I would 100% measure the big end with dial bore gauge to see how round it still is and would recommend at very least to plastic gauge them but that wouldn’t tell ya how true the big end is.

Edit: just re read your post and if you are using aftermarket rods that does change things for the better and while it wouldn’t change the specs as much as a stock rod it would still change the big end size slightly. Still not the way I’d go about it but guys throw rods in these things all the time with zero measuring without issues, just not the way I’d go about it. Sorry for long post and my 2cents

[RC200]

Yes, aftermarket 4340 forged conrods (H beam profile).
I don't see how it could be out of spec in term of clearance with:
_conrod big end diameter: 57.60mm
_OEM used crankshaft min 53,958 mm max 53,978 mm
_Kolbenschmidt STD bearings thickness 1,806 mm
_Elsawin specs:
clearance when new 0,015 ... 0,062 mm
max used 0,12 mm

At the worst, the bearings will wear a bit

I assume 10Nm to rotate the crankshaft by hand is in the ballpark of the acceptable torque.

[okkim]

The big end roundness can go out of shape if you tighten the rods tighter than the specified value. You should not use bigger torque for "just in case". It can overstretch the bolts too.

[Silverex]

Yes, aftermarket 4340 forged conrods (H beam profile).
I don't see how it could be out of spec in term of clearance with:
_conrod big end diameter: 57.60mm
_OEM used crankshaft min 53,958 mm max 53,978 mm
_Kolbenschmidt STD bearings thickness 1,806 mm
_Elsawin specs:
clearance when new 0,015 ... 0,062 mm
max used 0,12 mm

At the worst, the bearings will wear a bit

I assume 10Nm to rotate the crankshaft by hand is in the ballpark of the acceptable torque.

+2 on what Okkim said. That’s what I was getting at.

Also basically no set of rods is going measure out exactly the same, yes they will be within the manufacture specs but there will be some variation. Same for the bearings and like you mentioned the journals on crank vary also. All of them combined can end up making the clearance on a rod too tight and why you should measure so you can juggle the parts around to get the clearance that you’re after....that’s the difference on someone that throws a engine together and someone who builds one to their specs.

Yea you are correct worst case the bearings will be too tight and have premature wear/life.

10nm to rotate crank does sound right about what mine took to spin but that’s not really telling you if bearing specs are too tight more so the mains.

In my opinion if you still have engine on stand I’d pull upper pan/oil pump and check the bearings with a plastic gauge for piece of mind. Won’t tell you if the rods are out of round but atleast you’ll know if they are too tight and it will only be a couple hours of work and cost ya like a buck. That way you can also use ARP lube and retq the rods correctly.