Stocker

You are going to have a grenaded engine dude. You need to spend about a month reading all the old threads here, then read the *really* old threads at HA. This is one of those questions which is so basic, it should require little-to-no research when planning to go as deep into an engine as you want to.

No. ARP studs and OEM head bolts do not install even remotely the same.

JonGTR

Information for purchasing Main Studs:

1. You can buy a kit from Atomic Speedware for $117.50 plus about $20 shipping. $137.50 shipped. I believe this is the only store that has a "kit".


2. Or you can buy from Jegs individually. The AM 3.800-1lb stud was priced incorrectly at $25 each. So I called and corrected them. It's now $4.99 each. The washers are $.99 and the nuts are $3.99. Total of $99.70 for 30 pieces plus $10 handling and free shipping.
Grand total from Jegs = $109.70 shipped! wink1.gif


So you save almost $30 by doing a little research and knowing your part #'s.







edit:

Scratch that! When placing the order, the Jegs rep found 10 packs! They came out cheaper.

(10) AM3.800-1lb studs is still $49.90
"10 pack" of washers is part #200-8689 for $7.99
"10 pack" of nuts is part #300-8363 for $30.99


Grand total shipped from Jegs is $101.87

JonGTR

Please add to torque specs in my first post:

Torque Specs:
M10's = 60ftlbs. (with ARP lube)
M12's = 80ftlbs. (with ARP lube)
Rod Bolts = 50ftlbs. (with ARP lube)
Add a couple lbs if using regular engine oil.

supercow

Thanks jon, great info, I'll be making use of this when I rebuild my old motor.

JonGTR

Correct, they have different knurl diameters.



Factory size:

Front = .5629"

Rear = .5149"



Arp = .565"



So yes, you may be able to squeeze the ARP studs into the rear. It's only about 3/64" difference. It will be very tight and your results may vary. But like you said, if you need to bore out the hole a little more, then do so.



The length of these studs are roughly 1 1/2" longer than stock, so you will need open ended lugnuts.



I'll update the op to reflect.

tdonnell

Just an FYI for everyone out there interested in going with ARP studs that you can get stronger M10 head studs if you are going to run high boost and require extra torque to keep the cylinder head down. I went through two head gaskets in less than 1000 miles running 30-31 PSI of boost on E85. After a substantial amount of research regarding head studs, torques, preload, pushing coolant etc., (DSM websites are a great resource for us on this). I've realized that I've got the standard ARP head studs which are 190,000 ksi. (standard studs will have "ARP ARP stamped into the top of the stud where the allen key is, "ARP 2000" will be stamped into the 2000 studs in this location).



I just ordered 8 M10 ARP 2000 head studs which are 220,000 ksi. The standard studs are supposed to be torqued to 60 ft/lb with ARP lube. I've already exceeded that at 70... The 2000's are specified to be torqued to 70 ft/lb. These torque ratings put the studs at 75% of their yield (fracture) point. So I figured if I upgrade to the 2000's I can torque them safely to 80 ft/lb. I only upgraded the M10's because the M12's are rated for 110 ft/lb and I'm not going to torque them that high anyway (I went to 95 this time). One difference between the M10's I currently have and the 2000's is the thread pitch on one end. One is 1.25 but the other is 1.5... After a large amount of research I determined the applied torque of a bolt with the same diameter and 1 thread pitch level change is less than 5%. If anyone is interested in getting the 2000's instead of the standard ones the P/N is AM4.500-2B. They are 11.15 each. Then you'll need M10x1.5 flange nuts which are 10 bucks a pair. I'll actually be threading the top of the studs into the block since the top is the 1.25 thread pitch and using the nuts on the top at 1.5. This is fine according to ARP, who also said the applied torque with the thread pitch change is negligible...



Also note that you should re-use the washers from the factory head bolts when installing these studs. The ARP studs have a much smaller OD (by about .150"), which can cause the aluminum of the cylinder head to crush slightly when torqued to the higher values. I had this problem more on M12's, it actually crushed the aluminum enough to cause the top of the hole in the cylinder head to get small enough that I had to tap the stud out of it... The machine shop fixed that issue by cutting some of the material off with a special drill bit (leaving a new flat surface for the washer to seat against. Also remember to use moly lube on the stud threads (both ends), on the top and bottom of the washers, and on the washer flange of the nuts. This ensures proper torque application. I felt the difference when torquing them down this time, less twisting of the studs.



Might as well go with the stronger studs if you are investing in them.

Regit

I may upgrade mine next time the head comes off then !.. Thanks for the knowledge tdonnell !

supercow

Thanks Jon! I've used your research to purchase the wheel studs and today I ordered the head studs.

JonGTR

bmxer

Lots of specs
http://turbokia.info/index.php?id=arp