ARP head stud torque for a Miata.
#44
Received an email from ARP after the floods destroyed all our build diarys,
Sorry to hear you lost some things in the flood! Here are the torque
numbers you need. They are the same for both the ARP Ultra Torque and
ARP Moly Lube.
Rod Bolts 118-6401 = 38 ft/lbs
Head Studs 218-4701 = 80 ft/lbs
Main Studs 218-5401 = 60 ft/lbs
Regards,
Alan Nichols
Sales & Technical
Automotive Racing Products
1863 Eastman Ave.
Ventura, CA 93003
Toll Free: 800-826-3045
Ph: 805-339-2200
Fax: 805-650-0742
Email: alann@arpfasteners.com
www.arp-bolts.com
So I think I follow Savs recommendations
Terry
Sorry to hear you lost some things in the flood! Here are the torque
numbers you need. They are the same for both the ARP Ultra Torque and
ARP Moly Lube.
Rod Bolts 118-6401 = 38 ft/lbs
Head Studs 218-4701 = 80 ft/lbs
Main Studs 218-5401 = 60 ft/lbs
Regards,
Alan Nichols
Sales & Technical
Automotive Racing Products
1863 Eastman Ave.
Ventura, CA 93003
Toll Free: 800-826-3045
Ph: 805-339-2200
Fax: 805-650-0742
Email: alann@arpfasteners.com
www.arp-bolts.com
So I think I follow Savs recommendations
Terry
#45
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Thread Starter
Join Date: Jul 2005
Location: Anacortes, WA
Posts: 2,478
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Received an email from ARP after the floods destroyed all our build diarys,
Sorry to hear you lost some things in the flood! Here are the torque
numbers you need. They are the same for both the ARP Ultra Torque and
ARP Moly Lube.
Rod Bolts 118-6401 = 38 ft/lbs
Head Studs 218-4701 = 80 ft/lbs
Main Studs 218-5401 = 60 ft/lbs
Regards,
Alan Nichols
Sales & Technical
Automotive Racing Products
1863 Eastman Ave.
Ventura, CA 93003
Toll Free: 800-826-3045
Ph: 805-339-2200
Fax: 805-650-0742
Email: alann@arpfasteners.com
www.arp-bolts.com
So I think I follow Savs recommendations
Terry
Sorry to hear you lost some things in the flood! Here are the torque
numbers you need. They are the same for both the ARP Ultra Torque and
ARP Moly Lube.
Rod Bolts 118-6401 = 38 ft/lbs
Head Studs 218-4701 = 80 ft/lbs
Main Studs 218-5401 = 60 ft/lbs
Regards,
Alan Nichols
Sales & Technical
Automotive Racing Products
1863 Eastman Ave.
Ventura, CA 93003
Toll Free: 800-826-3045
Ph: 805-339-2200
Fax: 805-650-0742
Email: alann@arpfasteners.com
www.arp-bolts.com
So I think I follow Savs recommendations
Terry
Bob
Last edited by bbundy; 02-03-2011 at 01:06 PM.
#50
I torqued mine to 80ft/lbs a couple years ago, which seemed ridiculous when torquing them down at the time. I have, however, ran the engine without a belt on the water pump for 40 minutes in traffic (Had no water temperature gauge) before the upper radiator hose literally blew off the radiator. In normal cases with factory head studs, this would call for the head to be machined for sure. I just put the hose back on, threw a belt on, filled up, and I haven't lost coolant ever since.
#51
Former Vendor
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Location: Sunnyvale, CA
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Surprising that ARP would tell you this. The ARP2000 bolts that M-Tuned ships with their rods specify a stretch spec, not a torque spec. I've found that in order to get the ~.005-.006" stretch spec (IIRC), they wanted around 55-60ft.lbs of torque, not 38.
#53
Sorry to bring this back up. I just pulled the head, and plan on installing the new gasket this weekend. I originally torqued the nuts to 80 ft lbs per the instructions using the arp moly lube. After reading this thread it sounds like 65 lbs is a better option. Do I need to get more arp moly, is there a substitue, and do I need to measure the length of the threads for stretching with a micrometer? Keep in mind the threads had moly only when initially torqued, and now they will probably have a little oil on them. What is the recommendation for this scenario.
EDIT: It appears that ARP is now using the "ultratorque" lube which really minimizes the variance between torque stages. I think I screwed the pooch by tightening once, then immediately checking the torque again then buttoning everything up and never looking back. It appears that a person should probably use 8 separate torque cycles at the desired torque. How many cycles leading up to the desired torque before starting the 8 cycle retorque session? How long between cycles should a person wait before starting the next torque cycle???
Example: Pre torque 25%, 50%, 75%, 100% then 7 more cycles at 100% torque
EDIT: It appears that ARP is now using the "ultratorque" lube which really minimizes the variance between torque stages. I think I screwed the pooch by tightening once, then immediately checking the torque again then buttoning everything up and never looking back. It appears that a person should probably use 8 separate torque cycles at the desired torque. How many cycles leading up to the desired torque before starting the 8 cycle retorque session? How long between cycles should a person wait before starting the next torque cycle???
Example: Pre torque 25%, 50%, 75%, 100% then 7 more cycles at 100% torque
Last edited by miatauser884; 10-13-2011 at 11:37 AM.
#54
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Sorry to bring this back up. I just pulled the head, and plan on installing the nw gasket this weekend. I originally torqued the nuts top 80 lbs per the instructions using the arp moly lube. After reading this thread it souns like 65 lbs is a better option. Do I need to get more arp moly, is there a substitue, and do I need to measure the length of the threads for stretching with a micrometer? Keep in mind the threads had moly only when initially torqued, and now they will probably have a little oil on them. What is the recommendation for this scenario.
In for answer.
#55
Just an FYI. This is why I said eight cycles to tighten. Then if you use assembly lube or motor oil you can be sure that you are getting the torque that you want. It also appears that a torque cycle is defined by tightening to spec, then loosening. I was unaware of this. I thought it meant tighten to spec, wait for any stretching then hit it with the torque wrench again to check. Using ARP assembly would clearly save a bit of time.
#56
That is very good info. Thanks for sharing.
I will say that the BP is not known for blowing head gaskets, and unless you are building a mega high horsepower motor, 8 torque cycles, tightening and loosening, and choice of lubircant is not overly important. Clamping a miata head to block is pretty forgiving of discrepencies in technique, with the exception of over torquing which has already been discussed.
I will say that the BP is not known for blowing head gaskets, and unless you are building a mega high horsepower motor, 8 torque cycles, tightening and loosening, and choice of lubircant is not overly important. Clamping a miata head to block is pretty forgiving of discrepencies in technique, with the exception of over torquing which has already been discussed.
#57
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There is no time component to fastener stretch. It stretches as soon as you preload it.
8 torque cycles is absolutely ridiculous. Use their recommended lubricant, torque it in 3 steps, and don't untorque it. All you are doing is uncompressing and recompressing the gasket, which is a bad idea.
8 torque cycles is absolutely ridiculous. Use their recommended lubricant, torque it in 3 steps, and don't untorque it. All you are doing is uncompressing and recompressing the gasket, which is a bad idea.
#58
There is no time component to fastener stretch. It stretches as soon as you preload it.
8 torque cycles is absolutely ridiculous. Use their recommended lubricant, torque it in 3 steps, and don't untorque it. All you are doing is uncompressing and recompressing the gasket, which is a bad idea.
8 torque cycles is absolutely ridiculous. Use their recommended lubricant, torque it in 3 steps, and don't untorque it. All you are doing is uncompressing and recompressing the gasket, which is a bad idea.
#59
Back from the dead.
I just called FM and they say the 48lb ARP head stud number is not used by them anymore. They said 60-65lb for both the ARP head and main studs when using the ARP moly lube.
Why would we want to exceed the OE torque spec and thus clamping force if we know that the ARP studs are already stronger than OE bolts? Isn't the benefit in using the stronger studs? Or is there something to be gained by increasing the clamping force?
I'm reluctant to use ARP main studs at a higher torque if it forces a line bore since it adds $$$ to the build.
I just called FM and they say the 48lb ARP head stud number is not used by them anymore. They said 60-65lb for both the ARP head and main studs when using the ARP moly lube.
Why would we want to exceed the OE torque spec and thus clamping force if we know that the ARP studs are already stronger than OE bolts? Isn't the benefit in using the stronger studs? Or is there something to be gained by increasing the clamping force?
I'm reluctant to use ARP main studs at a higher torque if it forces a line bore since it adds $$$ to the build.
#60
The increased yield of the material is of little use in stock preload applications. The modulus of elasticity which would determine the "clampyness factor" is pretty well absolutely constant for most steels. Unless you need a higher torque load on the bolt/stud the additional material strength isn't going to do you any good. In short... the studs should not apply any additional clamping force under stock pre-load. Higher then stock pre-load can cause problems as mentioned...
That being said, the tensioner bolt on my power steering pump broke today. I could just be bitter.
That being said, the tensioner bolt on my power steering pump broke today. I could just be bitter.