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Frallan wrote: What is a back pressure hose?

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).
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.

Ohh, stupid me. I should stop asking questions after midnight. Tuuurbo....I forgot.
Cannot see how a loss in exhaust pressure through the hose should....maybe.

HUD, cool!

Still have to repeat that a 40 minute stint is demanding for any car and to do it with a ACVW turbo is amazing and for the driver too.

No worries
I thought the imbalance (one cylinder has no back pressure, the other three 1 bar EBP could do some main bearing harm at 7K+ rpms, but true, I dunno 4sure.
Thanks

Frallan wrote: Cannot see how a loss in exhaust pressure through the hose should....maybe.

me to .
i assume that hose for measuring backpressure is not that big.
IMHO the pressure inside the header equalises anyway.
so you have the same pressure "all around"

how about oil pressure during hard cornering? is that stable?

fastback wrote:how about oil pressure during hard cornering? is that stable?

Dry sump. Should be stable but can start foaming and be a hidden variable.

^^ yes, very stable because of dry-sump.

Everything fixed in time and ran a 11.0 @ 125mph at Santa Pod two weeks ago


Last sunday I put on my normal wheels again and ran with the last round for the Time Attack championship. With the upgrades the car went a full 4 seconds faster lap-time in warm-up session before I was deemed too noisy and wasn't allowed to run any further...still very happy with the result, but also wondering what if I could have run qualify-session as well. Still, engine is well and I didn't crash, so I drove back home on my own wheels as usual

Here's when they tell me I was over their limit..(usually never a problem on this track with my exhaust set-up before..? so it was a little bit of a surprise)

Volkswagen Beetle by Alex Kamsteeg, on Flickr

Some friends put a go-pro in my car, so if it works out, I may be able to upload some video in a week or so.

LIKE button Click

Wally wrote:^^ yes, very stable because of dry-sump.

Everything fixed in time and ran a 11.0 @ 125mph at Santa Pod two weeks ago .......

.........Last sunday I put on my normal wheels again and ran with the last round for the Time Attack championship. With the upgrades the car went a full 4 seconds faster lap-time in warm-up session before I was deemed too noisy and wasn't allowed to run any further......

Here's when they tell me I was over their limit..(usually never a problem on this track with my exhaust set-up before..? so it was a little bit of a surprise)
...........

Congratulations on the 11 second 1/4! That is REALLY hauling the coals!!!!!

What if any muffler are you using?

What are the heads temps now with the new cooling system?

CobraJet wrote:What if any muffler are you using?

What are the heads temps now with the new cooling system?

I use a 3,5" Borla oval shaped muffler in a considerable length. The wastegate even has its own, seprate, muffler, even longer in length..

Temps are the same-ish now as before. I have since disconnected the head temp gauge as I needed room for other gauges, so I wouldn't know what/when exactly anymore, but obviously it cools enough for my use with my engine (alu cylinders)

Nice times Wally!! And you car aint exactly a light weight either!! Good Work!!

Turned up the boost some more at today's dynoday and the engine takes anything you throw at it..
465 hp and 564Nm (418lbs.ft) @ flywheel:

nice!

At less than 6500 rpm. Yepp, that is torque too.
Well done...I think i have said that before.

465hp.... fk
And here I am battling with my 2332 T1... Well done Wally!!