head lifting?
#33
Nordschleife Master
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Originally Posted by Driftomagnifico
Aluminum block isn't the issue, it's the thread engagement and mechanics surrounding it. How many bolts does the 951 2.5L have? 14mm is a beefy bolt; that alone has much more frictional area and less fatigue pressure than what I am using.
Can you shoot out the installation specs on the headstuds? Things like torque (measured in angle or force?), what oil grade does it suggest, etc. I'm wondering if some of these guys are picking up excessive frictional resistance that is essentially causing them to undertorque the bolts.
The bolt itself might be strong, but there are other variables.
Can you shoot out the installation specs on the headstuds? Things like torque (measured in angle or force?), what oil grade does it suggest, etc. I'm wondering if some of these guys are picking up excessive frictional resistance that is essentially causing them to undertorque the bolts.
The bolt itself might be strong, but there are other variables.
The block has 10 headstuds. Installation is in 3 step's. 20 nm, 90 deg, 90 deg.
Factory says engine oil on the studs.
#34
Rennlist Member
Thread Starter
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"The block has 10 headstuds. Installation is in 3 step's. 20 nm, 90 deg, 90 deg.
Factory says engine oil on the studs."
Yep, that's exactly the specs my guy came back with.
So, ended up doing this re-torquing route, and we'll see what happens. I'll be boosting this weekend.
Factory says engine oil on the studs."
Yep, that's exactly the specs my guy came back with.
So, ended up doing this re-torquing route, and we'll see what happens. I'll be boosting this weekend.