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Pics below show the process of installing the exhaust manifold. Took ~1-1.5 hours doing everything slowly. Double nut the Mamba M6 studs to pre-torque them into the head to 7 lb-ft with anti-seize (stock factory studs are 9 lb-ft dry). Studs were flipped over and long threads installed into the head to minimize risk of stud/thread pullout. Flipping the studs over and using (2) washers under the nut to gain clearance on the unthreaded stud shank when the EM is installed is the more reliable method with aftermarket studs. Pulling a stud/thread out of the head at this stage is absolutely going to ruin your day so you want the maximum stud length engagement into the cylinder head as possible while using a torque wrench.
The manifold & head flatness play a critical role in keeping the studs/threads intact and it's an important step so don't skip checking that. Stud nuts with (2) washers & EM installed were then torqued to 20 lb-ft using anti-seize (25 lb-ft using OEM studs dry) as well with a torque wrench in the proper sequence. Note here that when I use anti-seize or oil on a fastener I'll torque to 80% of recommended torque to account for the friction reduction, otherwise you risk snapping a bolt. The factory copper nuts are lock nuts so keep that in mind when using aftermarket 12 pnt nuts as the risk of nut loosening is higher.
Anyhow, the exhaust manifold flatness was checked and being new it was dead flat. EM cylinder head surface flatness was not perfect and when I did the cylinder head way back when I took a hand file and made that mating surface flat to about .002" followed by a 320 grit surface finish. Most auto machine shops typically won't touch those surfaces unless they have a CNC so that's something to think about. Picture below shows the factory EM gasket which is a multi-layer embossed gasket which is almost overkill level of design to keep a tight seal. That EM gasket actually came in the $121 engine gasket overhaul kit and worth the money.
Going to install the cam position sensors & crank angle sensors tonight/weekend while I'm bored and waiting on a few things. Next week the remaining engine sensors and coil packs go on order. List of things to do on the engine is getting short.
The manifold & head flatness play a critical role in keeping the studs/threads intact and it's an important step so don't skip checking that. Stud nuts with (2) washers & EM installed were then torqued to 20 lb-ft using anti-seize (25 lb-ft using OEM studs dry) as well with a torque wrench in the proper sequence. Note here that when I use anti-seize or oil on a fastener I'll torque to 80% of recommended torque to account for the friction reduction, otherwise you risk snapping a bolt. The factory copper nuts are lock nuts so keep that in mind when using aftermarket 12 pnt nuts as the risk of nut loosening is higher.
Anyhow, the exhaust manifold flatness was checked and being new it was dead flat. EM cylinder head surface flatness was not perfect and when I did the cylinder head way back when I took a hand file and made that mating surface flat to about .002" followed by a 320 grit surface finish. Most auto machine shops typically won't touch those surfaces unless they have a CNC so that's something to think about. Picture below shows the factory EM gasket which is a multi-layer embossed gasket which is almost overkill level of design to keep a tight seal. That EM gasket actually came in the $121 engine gasket overhaul kit and worth the money.
Going to install the cam position sensors & crank angle sensors tonight/weekend while I'm bored and waiting on a few things. Next week the remaining engine sensors and coil packs go on order. List of things to do on the engine is getting short.