s&s. yes the head bolts really stretched. now not all did. but a couple. and when i say stretch, i mean stretch. i basically use the 3 stage torque, meaning i start at 35# go in sequence, then up to 50#, and then finally at 65# useing ARP lube. (thats what ARP recommends). on a couple bolts i couldnt even get to the 50# mark. i thought i was stripping the threads at first because it just felt like it kept turning and not getting tighter. back it out, check the block,bolt, and nothing, threads looked fine, so i reinstall and try and get a torque on it. no way its just not going to happen. remove it again and now compare it with another bolt and notice how much longer it is now. hummmmm? must be a bad bolt. fortunatly i did have another set of ARP bolts, they were for a genV with iron heads but there was a match in size so i used it. after the entire deal i ended up with three bolts from the original set that stretched. Mike at REX marine saw the stretched bolt and said he had never seen one do that before. we figured it must have been a bad batch. mike gave me a new set and ARP was awsome and even sent me another set for the genV i had to rob from. with all that said and the heads sealed real nice right now, you can understand the hesitation i have about wanting to remove the heads for the cam change. if i had a few seasons on it id have no problem with it but all this was done last season just before CBBB. trust me, id love to take the heads off again, clean em up, relap the valves, and do the spring swap and check clearances the easy way, but i just have that thought in the back of my mind and dont want to lose river time.
Victor...I'm pretty sure that if the bolts you have in there now didnm't stretch the first time around, they're not going to stretch now. Either they will, or won't the first time. Bolts don't lose their temper under normal conditions. Just a thought. I wouldn't worry about it.
I have heard that you can reuse them but why? Think about $100 or a new motor $$$$$$. Thats the way I think about it. I hate to do it but I dont want to buy a new motor when I can spend the few extra $ to have peace in my mind. If you really have to just be careful. Good luck with however you do it.
396
well thanks for all the responses but once again i must be thinking out my ars. after a good while to think about it i realize that i will just put this off untill i can get all the funds i need and gather all the parts. i agree with with doing it right the first time. plus its allways nice to freshen up the valves and clean up the ports and combustion chamber. to give you folks an insight of why i was so gun ho on doing this is that my current cam has a 110 overlap and ive been having water issues at low rpm and ive been pulling skiers which involves alot of low rpm while setting up. so i didnt want to damage the motor so doing the cam swap with a 112 over lap sounded like a great idea. plus the increased lift and more cam timing would be a great plus for performance. my current cam is very small for its application but i do enjoy the low end torque it gives. i guess ill just be happy with what i have for now and slowly collect all the proper items needed. thanks again for all your input.
well thanks for all the responses but once again i must be thinking out my ars. after a good while to think about it i realize that i will just put this off untill i can get all the funds i need and gather all the parts. i agree with with doing it right the first time. plus its allways nice to freshen up the valves and clean up the ports and combustion chamber. to give you folks an insight of why i was so gun ho on doing this is that my current cam has a 110 overlap and ive been having water issues at low rpm and ive been pulling skiers which involves alot of low rpm while setting up. so i didnt want to damage the motor so doing the cam swap with a 112 over lap sounded like a great idea. plus the increased lift and more cam timing would be a great plus for performance. my current cam is very small for its application but i do enjoy the low end torque it gives. i guess ill just be happy with what i have for now and slowly collect all the proper items needed. thanks again for all your input.
Sounds like your headed in the right directionGood luck
396
s&s. yes the head bolts really stretched. now not all did. but a couple. and when i say stretch, i mean stretch. i basically use the 3 stage torque, meaning i start at 35# go in sequence, then up to 50#, and then finally at 65# useing ARP lube. (thats what ARP recommends). on a couple bolts i couldnt even get to the 50# mark. i thought i was stripping the threads at first because it just felt like it kept turning and not getting tighter. back it out, check the block,bolt, and nothing, threads looked fine, so i reinstall and try and get a torque on it. no way its just not going to happen. remove it again and now compare it with another bolt and notice how much longer it is now. hummmmm? must be a bad bolt. fortunatly i did have another set of ARP bolts, they were for a genV with iron heads but there was a match in size so i used it. after the entire deal i ended up with three bolts from the original set that stretched. Mike at REX marine saw the stretched bolt and said he had never seen one do that before. we figured it must have been a bad batch. mike gave me a new set and ARP was awsome and even sent me another set for the genV i had to rob from. with all that said and the heads sealed real nice right now, you can understand the hesitation i have about wanting to remove the heads for the cam change. if i had a few seasons on it id have no problem with it but all this was done last season just before CBBB. trust me, id love to take the heads off again, clean em up, relap the valves, and do the spring swap and check clearances the easy way, but i just have that thought in the back of my mind and dont want to lose river time.
Wow, that really surprises me about the ARP bolts... Their stuff is the best and the quality control systems are second to none. Were these brand new bolts? The only way the could have stretched is, 1) bad lot from ARP and were not heat treated correctly (unlikely in my opinion, but possible) 2) Bolts got annealed somehow. Again unlikely since to anneal a high strentgh alloy you are talking around 1500 degrees 3) Bolts got torqued passed their yield point. Torque specs for ARP are based on 75% of yield strentgh. Say for instance if a bolt lubed with ARP moly lube got torqued to the 30 wt. oil spec, that would yield the bolt. Once you pass the yield point they are done and will stretch like a rubber band until they break...
S&S
to give you folks an insight of why i was so gun ho on doing this is that my current cam has a 110 overlap and ive been having water issues at low rpm and ive been pulling skiers which involves alot of low rpm while setting up. so i didnt want to damage the motor so doing the cam swap with a 112 over lap sounded like a great idea.
I thought you were running the banderlog? Still have water issues?
Wow, that really surprises me about the ARP bolts... Their stuff is the best and the quality control systems are second to none. Were these brand new bolts? The only way the could have stretched is, 1) bad lot from ARP and were not heat treated correctly (unlikely in my opinion, but possible) 2) Bolts got annealed somehow. Again unlikely since to anneal a high strentgh alloy you are talking around 1500 degrees 3) Bolts got torqued passed their yield point. Torque specs for ARP are based on 75% of yield strentgh. Say for instance if a bolt lubed with ARP moly lube got torqued to the 30 wt. oil spec, that would yield the bolt. Once you pass the yield point they are done and will stretch like a rubber band until they break...
S&S
so basically what you are saying is that i over tightened the bolts. even though the spec sheet say to tighten to 80# useing a quality 30wt oil, and 65# useing thier ARP lube. you apperantly didnt read the part were i couldnt even get to the 50# mark, so wether i used oil or thier lube, at what point did i pass the yield strength? also if you read in the post i said i used a replacement bolt from another set and it was fine. now i do agree that #2 would be unlikely unless the back of the UPS truck got ubove 1500 degrees, but you also say its "unlikely" that it could have been from a bad lot. well your opinion is your opinion, but thats the reasoning ARP gave me at the time , saying "we did have a bad batch (or lot)" also saying something like they tried a differant supplier or something like that. now by the information you give you seem to have some great knowlwedge of this and are probably a great engine builder, but from the way i was reading your post you basically say its unlikly that the bolt was faulty and that i must have over tightened it. well again, your opinion.
dan, the water issues i have are when i slow down and idle the water still seems to be coming into the headers. and after rethinking and checking my set up i noticed that the water lines and the "T" that supplies the headers are above the header inlet lines, so im now thinking im just siphoning whats left in the lines even though the banderlog is closed. i changed the lines yesterday so all water lines are below the headers and will test this soon.
so basically what you are saying is that i over tightened the bolts. even though the spec sheet say to tighten to 80# useing a quality 30wt oil, and 65# useing thier ARP lube. you apperantly didnt read the part were i couldnt even get to the 50# mark, so wether i used oil or thier lube, at what point did i pass the yield strength? also if you read in the post i said i used a replacement bolt from another set and it was fine. now i do agree that #2 would be unlikely unless the back of the UPS truck got ubove 1500 degrees, but you also say its "unlikely" that it could have been from a bad lot. well your opinion is your opinion, but thats the reasoning ARP gave me at the time , saying "we did have a bad batch (or lot)" also saying something like they tried a differant supplier or something like that. now by the information you give you seem to have some great knowlwedge of this and are probably a great engine builder, but from the way i was reading your post you basically say its unlikly that the bolt was faulty and that i must have over tightened it. well again, your opinion.
I'm pretty sure there's no way you'll ever over tighten a head bolt like that...especially an ARP. You'll rip the threads outa the block first.
I'm not sure about ARP using a different supplier, since they are the supplier. They mfg. everything in house, heat treat, etc, but it's not unlikely that they had a bad batch. Feeces occurs. Point is, they stepped up and took care of you, and from what it sounds like, you did everything you were supposed to. :coffeycup
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