It's been a while since my last update and as the project will be complete in a few days I decided to sum up all the mods and all the problems I had to face because hitting 300+bhp isn't a walk in the park.
Let me remind you that my last update was about the misfires I was having especially in cold weather and on high boost, so my tuner had written a really light file where I could go easily to 150kmh but then my dashboard was lighting up like a Xmas tree.
So since I had become best buds with the check engine light and we had figured out that the misfires were caused by the weak exhaust valve springs I decided to change them. Since we couldn't find any springs from Supertech we went for the uprated stiffer oem valve springs that all the latest '12 and on 1.4 tsi's have, ETKA code 036109623AC (in case anyone wants to change them), which are color coded in red and not green as I'd read in another forum. They're much stiffer than what I had, so much that you can feel it in your hands.
The project was carried out by Derekidis Service, where he used a special tool that compresses the cylinder so that the valves won't drop inside (sorry I can't describe it any better). It took him 4 days as he works alone. Total cost including labor and an oil change less than 500 euros.
Some pics from the whole valve springs process (I'll post some with the tool later):
So the misfires are gone but when we were logging the car on the 10th run it started to whistle/whine like it had a vacuum leak, after 4000rpm, and it wasn't holding boost. Back to the
shop, the mechanic inspected all the hoses for leaks but they were ok, so we checked the turbo too and it had some shaft play, unusual for the little time that I had it. So the turbo was sent to the turbo specialist for a check and service.
Here is when things started to get an interesting twist as the turbo specialist told us that the hybrid was partial, only the compressor wheel was k04-23 but the rest was stock!
When I decided to go hybrid several months ago I did the job through another
shop that sent the turbo to the specialist and made all the arrangements for me. I just told them what I wanted (full hybrid wheels, shaft, thrust, porting) and we agreed on everything including the cost. But they tricked me and told the specialist to change only the compressor wheel but they charged me for the whole hybrid! Apart from the cost what they did was dangerous too because I told my current tuner that I have a full hybrid and he wrote the tune (it's custom) according to the upgrades that I thought I had, so who knows what could have happened in time and on high boost (maybe the shaft play was a first sign?). So right now I have a full hybrid turbo and I'll post some pics later where you can see the huge difference in the turbine wheel.
But the damn thing wouldn't stop whining! So we decided to change the cooler with a bigger, wider, thicker one from China (by the way here everyone goes for a made in China universal cooler that are pretty good for the money). It's almost 11 liters rated for 350bhp and in several runs going in 4th and 5th to the redline with 30°C ambient, we logged 37°C tops. With my previous custom cooler we had logged 35°C with 15°C ambient. After it was fitted we went for a run and the whine was gone (something must have hit the old cooler and made a hole in it) BUT this time the wategate's membrane went bad and I was hitting 2bars boost lol. I'm taking the wastegate for a service next week and provided that everything else goes well we will tune it one final time in 2 weeks. Right now I have a stock wastegate on and the car holds 0.8 bar boost throughout the rev range.
Cooler pics:
VS the old one:
I hope that in my next update I'll have a dyno.
