I experienced some rattle right after cold startup if I let the car sit for a few days, so I figured the oil check valves had gone bad, or the oil distribution tube o-rings were shot. It’s not like I’d do this level of work and not replace them, but this problem was more incentive to do so…
Basically the whole reason why I pulled the engine was to deal with the turbo coolant return line leak. Not wanting to ever deal with that again, I researched replacement options and found that all of the turbo coolant lines are NLA, so I ended up ‘making’ my own using 3/8″ silicone tubing. If you split the factory swaged ends with two cuts, you’re left with a very nice barbed end. Oetiker clamps are a must for clearance and the smooth ID won’t nick the silicone.
The left side coolant feed got a link wonky, but I think it should be reliable.
The return lines came out quite nice.
I saw someone mention from-a-gasket shellac for coating copper crush washers. I’ve never experienced a leak from a properly torqued crush washer (and I’ve installed a lot of them), but given the consequences of a leaking crush washer on this car, I decided to give the shellac a try.
Almost every Volvo I tune benefits from a wastegate actuator upgrade, be it in a decrease in spool RPM or an increase in peak boost, or both. Granted, they come with the factory with quite weak wastegates that open around 3-6psi. I was on the fence about it, but in the end I decided it would be worth using Mamba’s wastegates. I kept the 12psi springs that were factory installed. Considering the small area of the wastegate flapper, I think 12psi should be fine for reaching the estimated target boost of 24-26psi. I measured the stock K04 wastegate at 4mm of preload and found that they start moving at 4psi and are fully open at 11psi. With the same 4mm of preload on the Mambas, they start moving at 6-7psi and are fully open at 15psi.
The Mamba WGAs are almost a direct bolt on, but the left side mounting bracket needs some grinding and the right side engine mount needs some clearancing. The mount is pretty thin where it needs shaving, so I ended up grinding through it, which needed some reinforcement. Unfortunately the cast aluminum bracket is terrible quality and welds like sh1t.
Think this is why I had vibration at idle???
I added an oil pressure sensor which uses a 1/8″NPT thread. I ordered a M10x1mm -> 1/8NPT adapter, but it was taking way too long in shipping, so I ended up making my own. I drilled a hole through the factory M10 cap, drilled and tapped a rod with the NPT thread and welded them together.
I bought literally the cheapest K04 inlets I could – they were less than $100 shipped. I fully expected to have to do some work to them for that price, which I did. The right side fit up perfectly, but the left side was way off and needed quite a bit more length to sit fully on the turbo inlet. The piping is 2″ and the kit came with straight 2″ couplers to connect to the bi-pipe, which is 2.25″. I probably could have stretched them to fit over the bi-pipe, but ended up getting some 2″ -> 2.25″ reducers.
