ARP L19 Headstud Length for Evo 9
Mar 19, 2019, 10:51 PM
#1
Newbie
Thread Starter
ARP L19 Headstud Length for Evo 9
I’m currently in the process of replacing a headgasket and all the other work along with it for my Evo 9. I was wondering what the original length of the studs should be? I’ve used these studs a few time and they’re not supposed to stretch, but this is the second headgasket I’ve blown in 1300 miles. Just want to make sure all of my studs are within spec before torquing the nuts down again. I’ve seen that they can stretch if you over torque them and I’m not sure if the previous owner has done that. I’ve searched for the length of the L19’s, but couldn’t find anything. Any help?
Last edited by Gschierm; Mar 19, 2019 at 11:13 PM.
Mar 22, 2019, 12:14 PM
#2
EvoM Guru
iTrader: (1)
Unless you measure them new, you won't know the actual original length to measure if they've stretched. That being said, I'm sure they're fine.
Mar 22, 2019, 04:16 PM
#3
^ I'd agree.
OP, there might be another issue here that needs addressing. I would check the block deck itself to make sure it is true. Use a precision straight edge and try to slide a feeler gauge under it in numerous spots to see if it is misshapen. It could need machining. The service manual has a nice set of instructions that give you the acceptable values for warpage. Same goes for the cylinder head. Use only the OEM MLS head gasket. With the L19's, you can torque them from 90 to 100 ftlbs and they won't be ruined. Be sure to do so in 3 equal steps in the correct pattern.
OP, there might be another issue here that needs addressing. I would check the block deck itself to make sure it is true. Use a precision straight edge and try to slide a feeler gauge under it in numerous spots to see if it is misshapen. It could need machining. The service manual has a nice set of instructions that give you the acceptable values for warpage. Same goes for the cylinder head. Use only the OEM MLS head gasket. With the L19's, you can torque them from 90 to 100 ftlbs and they won't be ruined. Be sure to do so in 3 equal steps in the correct pattern.
Mar 26, 2019, 10:28 AM
#5
EvoM Guru
iTrader: (1)
95ftlbs is the highest I'd go if the head doesn't have steel inserts in the head stud holes. The nut/washer tends to really dig in to the head over time if you torque them more than that..