Bullet Proofing The C30. The Coolant System | SwedeSpeed

Heater Core Hoses

• Worth using do88 silicone hoses if I am going to reuse the plastic fittings?
• Has anyone had experience with REIN? Fraction of the price of genuine, but rather be safe than sorry… Might consider using REIN for new plastic connections for the do88.

The idea is to eliminate the plastic parts of the cooling system. What do88 says about to reuse all plastic fittings is completely idiotic. I wonder why they didn’t make a single piece hose instead of a two. Anyways, in my case, I bought genuine heater core hoses, because I needed the measurements of the male fittings so I could find and make an aluminum pipe to replace them. The bonus was they already had the female fittings in the other end, that I had to use at the firewall (the only ones I couldn’t find a metallic replacement). So yeah, as long you’re replacing the middle 4x plastic fittings with a metallic pipe (aluminum is the best option), you only need two new female fittings to connect at the firewall pipes out of hoses like this one:

Genuine Oil Cooler Hoses

• While I’m there… Is it worth upgrading to the Focus RS cooler? I’m located in Chicago on an Elevate tune w/Ko4 with DP, FMIC, etc. Might see 1-2 track days/auto cross a year. Mostly a daily.
  • If I upgrade to the Focus RS cooler, might as well take out the PCV. I’ve had no signs of a failing PCV so far. Hasn’t been replaced yet to my knowledge but I remember hearing the facelifts got an upgraded design PCV fixing the issues? If I should replace it, would it make sense to do the diaphragm or the entire assembly?

If you can, and don’t mind to replace it, sure, go ahead and do it. It helps to stabilize temperatures a bit more than stock unit. But the most important feature is that it helps to warm up the oil faster after a cold start, which is a good thing, considering you’re in Chicago. If you plan to track the car for extended periods of time, then you need an oil radiator, like the Elevate unit. BUT…… install a thermostat for it. Running that oil radiator without a thermostat in cold weather is asking for problems.

Regarding the PCV, if the plastic top part is still in good condition, you can pull it and clean it like I described in my thread here:

If not, go ahead and install a new unit. Do not half ass it by just replacing the diaphragm only without cleaning the cyclone separators.

Question: Has anyone replaced hoses #7 and #8? As much as we talk about watching the cooling system, I have never seen any mention of these hoses.

Anything else I am missing?

Good thing you mentioned those, I couldn’t find a silicone kit (Honestly, I didn’t really searched, but it’s on my pending list) with the correct shape for the curved hose. I saw do88 sells a different kit that might work (this one here), but I think it has two potential issues, first, it doesn’t say mention anywhere the ID size of the hose (the turbo hard lines are 10mm OD). And second, I’m not sure if that 45deg hose would not kink when installed, which if it does, then it would be a big problem.