I was measuring exhaust back pressure to see what the ratio boost-EBP was with this smaller turbo. As it has a pretty big hotside (A/R wise), but smaller wheels, I was interested to see what the difference was opposed to the equally sized compressor wheel of the turbo before that (30R Garrett with small A/R hotside).Frallan wrote: What is a back pressure hose?
That hose runs from one primaire runner and a heat sink to the gauge center bottom row on my dash. From the video I watched myself I just noticed that from 20 or 30 minutes onwards, the gauge doesn't respond anymore...
I crawed under the car and yep, the exhaust (back) pressure hose had indeed come off
The imbalance must have been doing some damage on the bearings, but just the first (thrust) one had 'gone'. Could just as well been unrelated, I dunno. These were the first time I used the 'new' Mahle bearings and maybe, just maybe they need the thrust one set a little looser then the old Kolbenschmidt's I was used to, so I did and set its axial play a few hundreds above the factory recommended value.
Must say they were awesome in embedding the alu residue in the softer first layer of the bearing (as it should) and still performing on the other two mains. Crank could be repolished (superfinished actually) on the first main only. The few thou less is no problem, maybe even a benefit on the first main. Rest of the bearing surfaces looked still perfect despite the alu shavings mess in the oil (Kendall racing-green GT1 20W50). The surface hardening the crank had undergone when the engine was build, payed itself too now I guess as without it the cranks journal damage would have been beyond a re-polish very likely.
What is that small black patch on your window?
Thats a patch for reflecting a head-up display device to show speed. However I didn;t use it on the track.
