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Repairs / Upgrades Part 2

After the last round of upgrades, the car began showing signs of a blown headgasket, so it is once again being pulled apart to replace/upgrade parts.
The main things that I hope to do this time round are:

I have also been doing some major front end modification to the car, improving airflow path around the front of the car ( Click here to see it )

Headgasket
Here's a picture of the damage to the headgasket ( pic )
The damage was just allowing combustion gasses to enter the water jacket under boost, boiling localised areas and eventually causing the coolant to leave the system as steam, until there was practically none remaining.
Picture of the Gen 3 MHG on the Gen 2 block ( pic ). The only parts of minor concern are little areas where the coolant openings coincide with divisions in the water jacket. I discovered the same thing occurs on Gen 3 blocks so I decided not to worry about it. Picture is two photoss joined together
Here is a comparison between the original gasket and the Gen 3 one. The main differences appear to be that the cooling is slightly reduced on the intake side (top in the pictures), possibly to improve fuel atomisation at low revs, since it doesn't have a system like T-VIS to improve air velocity. ( pic )

Upon stripping the engine I discovered some interesting things. First was that this water fitting on the back of the block was completely blocked with gunk, as was the rubber hose connected to it. ( pic )
This may have been the cause of, or a contributing factor to the headgasket blowing.

I also noticed some damage to the #1 piston. Rather than simple pitting like you normally get with detonation, this appears to be damage that would have been caused by a foreign object in the cylinder, possibly a spark plug electode or something. I will probably just carefully sand this out to stop the jagged points causing detonation. ( pic )

ARP Head Studs
OEM head bolts are torque-to-yield fasteners, meaning they stretch when installed. This means they aren't reusable. ARPs are stronger than OEM, reusable, and don't cost much more either, so it's a good idea to upgrade if you're pulling the head off. Mine took quite a while to arrive from 935motorsports.com, but they did eventually, and fortunately the long wait didn't hold me up. Here's a shot of them dummy fitted to the engine ( pic )

So after having the block and head resurfaced I reassembled the engine. I spent many hours cleaning virtually every piece of the engine, and painted many of them. Looks a heck of a lot better than before!
Assembly pictures (don't ask about the valve cover!):

And some install pics:

Some of the other things I did during this time were to make coolant hardlines to tidy up things some more ( more info ), make up a new intake ( more info ), tidied up the battery relocation with some fuses and such ( more info ), and I also redid the engine wiring ( more info ).

So, there is a bit left to go, I need to replace the valve cover gasket because it got pinched and damaged during install, and I need to make a heat shield for the firewall. I also plan to redo wiring to the fuel pump with some heavy gauge wire straight from the battery to reduce voltage drops.