Well, I got the intercooler pipe needed back off my mate who has done a sterling job of cutting and welding it to suit the turbo.
Took it out for a blast last night to see what the mani, decat and external wastegate are like, and oh my word! Feels soo much more better being able to keep my foot firmly down and not have to worry about boost creep and fuel cut! The wastegate has a 0.8 bar spring in it, so just a little over 0.1 bar over stock.
However, on the way back home, the coolant temp gauge just suddenly shot up and engine light came on. Immediately killed the engine and pulled in to find the bottom radiator hose had popped off and dumped all of its contents over the road, turns out the hose clip was never put back on properly! Got the hose on, clip on, filled the rad back up again, started her up and temp was back to normal and no engine light on. Top job.
Moved the car a bit and noticed a puddle darker than the rest, turns out it was oil!
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Now I'm getting worried, looked under the car to find the entire lower engine bay and suspension on the drivers side is covered, and I mean COVERED in oil, dripping. Started it up after checking there was still oil in the car, no knocking noises, no oil leaking out from anywhere on idle or on low revs. Hopefully it's just the banjo bolt on oil feed for the turbo not being tight enough at high revs
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Either that or my crank seal has given up on life. Seems to have come from the front of the engine block though, so hopefully it's the oil feed line.
Gingerly drove it home at low speed (only lived a mile away from where I pulled in), and I'm going to give it all a good check over tomorrow.