[Subscribe to Daily Digest] |
[Main Performance Bulletin Board | BBFAQ |
Prev by Date | Next by Date | Post Followup ]
Member Login / Signup - Members see fewer ads. - Latest Member Gallery Photos
Re: What do I re torque my headbolts to? ARP studs? Posted by JZW [Email] (#539) [Profile/Gallery] (more from JZW) on Mon, 14 Mar 2011 20:40:13 In Reply to: Re: What do I re torque my headbolts to? ARP studs?, 900 Aero [Profile/Gallery] , Sat, 12 Mar 2011 10:10:09 Members do not see ads below this line. - Help Keep This Site Online - Signup |
Good info, I have had multiple issues with the arp studs and I think I will give the taper grind a try. I have not had any issues with them sticking in the block, but I have had issues with high hp cars lifting the head. This is more explanation why this can happen.
I did some research and found many guys were reporting that the studs had to be pre-stretched at least 5 times to get the proper correct pre-load. Just by chance maybe, but my high hp Saab did finally seal with the arp studs on the fith torque.
My first experience was to torque to the recommended 80 Ft-lbs with the arp moly lube, my head lifted on the first pull and sprayed coolant all over the inside of my hood and blew junks of my head-gasket into my coolant system. I was not too happy :-(
I then saw a show on the speed chanel, hp tv on powerblock and they were demonstrating how the arp studs were not reaching the proper pre-load tension of 17,000 lbs at 125ft-lbs. They tested with motor oil and low and behold, it took 5 re-torques before the stud held 17,0000 ft-lbs of pre-load at 125 ft-lbs. They tested the older arp lube and it was going over by the third re-torque, drag race "peanut buter" was perfect the first time, but by the 4th-5th time, it went to 25,000+ and snapped the stud !!!
The new arp ultra torque also showed perfect 17,000 pre-load at 125 ft-lbs of torque and it was the same after mulitple torque sessions. I may give this new arp lube a try with my studs.
So, this is all good data, be careful with arp studs, they need to be pre-stretched with motor oil as the torque lube and I will probably pre-stretch them anyway, just to be safe when I buy a new set.
John
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.