Glad you have put this video up I'm in the middle of a headgasket replacement well have been waiting on parts for 3 weeks and have probably another 3 weeks waiting on my cometic headgasket. I put a felpro headgasket on and used the head studs from arp and I made it 300 miles and it let go found out later that the felpro gaskets along with the cummins ones are junk so I have found through research. I really wasn't happy with myself for not hot re-torqueing the studs till I found the gasket would have crapped out anyway. My head is at the machine shop getting checked out currently.
Yeah I'm not sure what mine puts down but it's over 400 for sure planning on getting it on the dyno this summer if everything works out to find out what she does put down! By the way i transplanted my 12 valve into a 2005 chevy 2500hd cclb has an nv4500 behind it and the factory pushbutton 4x4 from the chevy really fun project love the way it drives compared to the ol 97 2500 ram it came out of
I yield my bolts by building a blank I can torque them into and then yield the bolt by heating them up in the oven. My Cummins blank has a blank with 26 sockets to tighten the studs to torque and then heat them to 220 in the oven, then retorque and cool and then measure the amount of stretch the bolt has. Arp 2000 yield is about .023 thou.
I wonder what the torque is say you torque them to 125 hot. And then cold are they like 135 ish ft lbs. it would be nice to know IV never actually measured
Evey time it heats up that gasket gets crushed & never spring back to its original size, not by much but some, and it accumulates, so if the bolts/studs/fasteners aren't in their elastic range, there is less clamp on the gasket.
I never used the studs on a Cummins although I think its a good idea and I do them if I ever in my motor . Many years ago some of the guys who were building hot rod motors had talked about re torque on the head bolts , no idea if that is of any value and also installing studs one at a time while the motor is together and in the truck .
So when you say "hot retorque" I assume you mean just putting a torque wrench on it and pull to it clicks or beeps on the desired torque, correct? Not loosening the nut, reapplying lube and starting over like when you first installed them, correct?
I would've thought that the Cummins engineers would have considered expansion and contraction factors when specifying torque values. Does this theory only apply to performance engines?
@@CUTTERUPROB Come to think on this info...I would love to know how many tons per square inch the head bolts exert on the gasket after being torques down. Nonetheless, the compression still can blow the gasket into a leak be it oil into coolant or coolant out the side.
I am doing a hot retorque on 96 12 valve and I cannot get to 3 studs that are blocked by hard fuel lines. What do I do? Thanks for all your knowledge. Vudy
Have to pull the lines off. If you pulling them off and just do those two and put them back on right away. You should be able to just fire it up with out priming the system agin.
So I did head studs on this new engine have 500 miles on it an I didn't do the hot retorque an I see that the head gasket is leaking in the front right corner from the outside... Think it's to late to try an save it?
@@CUTTERUPROB now I have a slight haze at idle exhaust smells different but no loss of coolant.. Egts are kinda low tried new injectors.. I am running a 50hp overflow an a fass 265 I believe
Do you think it is a good idea to retorque stock head bolts well I am putting in new Injectors and setting valves as some insurance until I blow the headgasket and switch to studs? Thanks
No, torque to yeild bolt means something diferent. Means the bolt actually goes past the yeild point on the stress strain curve and enters plastic deformation.
Look closely at your stock head bolt it will have a stretch zone engineered into it thats calibrated for a yield point where the bolt will actually deform and stretch. Sometimes you can see where they streatch and neck down. Thats why they are longer when you remove them, and why a lot of factory head bolts or some other critical fasteners are 1 time use.
I'm absolutely going to re-torque all my ARP head studs on my brand new built LS engine, after I drive it N/A for about one month. Just sucks to remove the valve covers to then remove the rockers in a 1998 Trans Am. But thanks for the vid to prove how much it stretches.
Great knowledge, that’s just straight facts! Just found you and subbed!
great demonstration by the wall, you're hitting all the salient points of making these things work well, good job bud
Thanks
Glad you have put this video up I'm in the middle of a headgasket replacement well have been waiting on parts for 3 weeks and have probably another 3 weeks waiting on my cometic headgasket. I put a felpro headgasket on and used the head studs from arp and I made it 300 miles and it let go found out later that the felpro gaskets along with the cummins ones are junk so I have found through research. I really wasn't happy with myself for not hot re-torqueing the studs till I found the gasket would have crapped out anyway. My head is at the machine shop getting checked out currently.
I have used flopro gaskets in lower hp applications without issue. But anything over 400 I don’t like them myself.
Yeah I'm not sure what mine puts down but it's over 400 for sure planning on getting it on the dyno this summer if everything works out to find out what she does put down! By the way i transplanted my 12 valve into a 2005 chevy 2500hd cclb has an nv4500 behind it and the factory pushbutton 4x4 from the chevy really fun project love the way it drives compared to the ol 97 2500 ram it came out of
I yield my bolts by building a blank I can torque them into and then yield the bolt by heating them up in the oven. My Cummins blank has a blank with 26 sockets to tighten the studs to torque and then heat them to 220 in the oven, then retorque and cool and then measure the amount of stretch the bolt has. Arp 2000 yield is about .023 thou.
I wonder what the torque is say you torque them to 125 hot. And then cold are they like 135 ish ft lbs. it would be nice to know IV never actually measured
Evey time it heats up that gasket gets crushed & never spring back to its original size, not by much but some, and it accumulates, so if the bolts/studs/fasteners aren't in their elastic range, there is less clamp on the gasket.
If you have new exhaust studs That would probably be another good one too do also.Great vids brother 🇺🇸🇺🇸🇺🇸
good ides
I never used the studs on a Cummins although I think its a good idea and I do them if I ever in my motor . Many years ago some of the guys who were building hot rod motors had talked about re torque on the head bolts , no idea if that is of any value and also installing studs one at a time while the motor is together and in the truck .
more clamp load is more clamp load
Do you do this with stock bolts too?
You can. I have done it. But technically a torque to yield you shouldn’t
So when you say "hot retorque" I assume you mean just putting a torque wrench on it and pull to it clicks or beeps on the desired torque, correct? Not loosening the nut, reapplying lube and starting over like when you first installed them, correct?
Yes he means just torque down the nut with the highest torque number when engine warm up. Puts alittle more pressure on head when it cools back down
Bagged1998 answered for me 😎
Good info
🙏
I would've thought that the Cummins engineers would have considered expansion and contraction factors when specifying torque values. Does this theory only apply to performance engines?
When using a stock bolt and at stock power yes. But even Cummins have revised there torque from the original.
I was talking more with studs
@@CUTTERUPROB Come to think on this info...I would love to know how many tons per square inch the head bolts exert on the gasket after being torques down. Nonetheless, the compression still can blow the gasket into a leak be it oil into coolant or coolant out the side.
Would you hot re torque an o-ring head and 625s on a mls gasket?
Yes, Couple times
@@CUTTERUPROB awesome thank you for the response!
I am doing a hot retorque on 96 12 valve and I cannot get to 3 studs that are blocked by hard fuel lines. What do I do? Thanks for all your knowledge. Vudy
Have to pull the lines off. If you pulling them off and just do those two and put them back on right away. You should be able to just fire it up with out priming the system agin.
So I did head studs on this new engine have 500 miles on it an I didn't do the hot retorque an I see that the head gasket is leaking in the front right corner from the outside... Think it's to late to try an save it?
Try it and see what happens
@@CUTTERUPROB now I have a slight haze at idle exhaust smells different but no loss of coolant.. Egts are kinda low tried new injectors.. I am running a 50hp overflow an a fass 265 I believe
Do you think it is a good idea to retorque stock head bolts well I am putting in new Injectors and setting valves as some insurance until I blow the headgasket and switch to studs? Thanks
I have done it before. But twice have broken a head bolt off as well. So just want to be carful
@@CUTTERUPROB thank you for the response maybe ill hold off on that then
@@CUTTERUPROB what were you torqueing them to when they snapped?
@@PortChopsGarage I personally just leave them and went you have a gasket issue just do a set of studs. Just my two cents
@@CUTTERUPROB 👌 that's what I'm thinking now thank you sir.
Does hot retorqing apply to head bolts as well with factory boost ?
Factory bolts are torque to yield so no on 24v but on a 12v there torque to angle bolts . But lots of guys to torque them over again after a few years
@@CUTTERUPROB Do you mean torque to angle ?
No, torque to yeild bolt means something diferent. Means the bolt actually goes past the yeild point on the stress strain curve and enters plastic deformation.
Look closely at your stock head bolt it will have a stretch zone engineered into it thats calibrated for a yield point where the bolt will actually deform and stretch. Sometimes you can see where they streatch and neck down. Thats why they are longer when you remove them, and why a lot of factory head bolts or some other critical fasteners are 1 time use.
@@CUTTERUPROB My first gen head bolts are torque to angle.
I'm absolutely going to re-torque all my ARP head studs on my brand new built LS engine, after I drive it N/A for about one month. Just sucks to remove the valve covers to then remove the rockers in a 1998 Trans Am. But thanks for the vid to prove how much it stretches.