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Yup, exactly. I mean fitting a custom 90 degree bend with holes for dump valve and n75 before the turbo, then fit another 90 or 110 degree bend to push the air filter down.
Here are a few pics of how it is on my friends 3076R car:
Yep I know what you meant I wouldn't fit it like that in my car due to the location of other items. I also prefer the smoother power delivery of not having bends before the turbo inlet.
Personally if I were to change anything now for more power I'd junk the motronic as even the rs4 maf wont flow enough. As the big power rs4's I've done have had to upgrade their maf for the same reason runing out of range at the top end.
If my system wasn't working however I would consider it a sensible upgrade for this powerband.
Back to the breather system, done a bit more testing today and it appears to not be a sucking issue on the turbo side as there is no oil in the turbo, boost pipes and intake manifold.
Also the oil level in the catch tank always fills to the same amount and the oil level on the dipstick always drops from the max level to minimum level mark.
I'm starting to wander whether the dipstick im using is reading the wrong level and im overfilling the engine.
Going to clean the whole breather system out and run it with a lower oil level to see if the problem goes away as previously all the catchtank used to collect was water vapour.
Personally if I were to change anything now for more power I'd junk the motronic as even the rs4 maf wont flow enough. As the big power rs4's I've done have had to upgrade their maf for the same reason runing out of range at the top end.
There's always the Pro-M MAF, which does over 1000hp
RS4 MAF tops out at around 640-660hp from experience. Your ECU is running completely blind after 5000 rpm though, and won't be able to compensate much for variations. Watch your AFR's closely.
Stroker crank will take up more volume in the sump and will 'disturb' more oil every time it enters the oil sitting in the base of the sump. This could be the same effect as you over filling it perhaps? The crank will be imparting more energy into the oil at the same time.
Perhaps another swirl pot or a different would help keep more of the oil in the sump? Although this is not an solution, more of a temporary fix.
Cheers'en, AndyC
1994 ABY Coupe - Projekt Alpinweiss
I know its running blind according to the zeitronix unit 4720 is where the MAF hits 5volts.
An 044 pump controlled directly of the battery via a relay and asnu injectors keep the fueling very linear and stable. AVCR boost controller ensures the boost curve remains consistent across all the gears.
Logs on dyno and road are so consistent to the extend I don't bother looking anymore. Its not an ideal way to map by any means in the same token very few aftermarket ecu's will compensate at the too end if any. Once again one relies on the skill level of the mapper and his ability to use the tools at hand. So I don't see any real concern for worry on the current setup.
I know its running blind according to the zeitronix unit 4720 is where the MAF hits 5volts.
An 044 pump controlled directly of the battery via a relay and asnu injectors keep the fueling very linear and stable. AVCR boost controller ensures the boost curve remains consistent across all the gears.
Logs on dyno and road are so consistent to the extend I don't bother looking anymore. Its not an ideal way to map by any means in the same token very few aftermarket ecu's will compensate at the too end if any. Once again one relies on the skill level of the mapper and his ability to use the tools at hand. So I don't see any real concern for worry on the current setup.
Thank-you for your info though :-)
Just a little correction - the stock MAF tops out at ~5.6 volts.
I don't see why that boost controller is needed, Motronic handles up to 2.9 bar boost just fine with a 4 bar MAP sensor... oh well.
The logs will change with IAT fluctuations. You'll run quite a bit leaner when ambient temps drop a lot, because the ECU is putting in a fixed amount of fuel and cold air is denser, and it can't see that. IAT correction is done only for hot air charge.
Stroker crank will take up more volume in the sump and will 'disturb' more oil every time it enters the oil sitting in the base of the sump. This could be the same effect as you over filling it perhaps? The crank will be imparting more energy into the oil at the same time.
Perhaps another swirl pot or a different would help keep more of the oil in the sump? Although this is not an solution, more of a temporary fix.
I thought about that but the dipstick tube and dipstick are of the diesel block so I assumed it isbthe correct level.
In the same token not running a diesel sump, also not running the diesel block breather bar that locates the block breather aperture at the front of the sump due to the girdle and ally sump being in the way.
Starting to wonder whether this is why Audi put in the bolt on breather channel because it is a common issue on the larger stroke crank?
@PRJ, interesting I always thought it was 5v as this is where the zeitronix unit flatlines.
Ambient temps don't concern me too much as it was zero degrees outside its only ever going to go richer.
As for boost control on stock management I went the 4bar vmap route on the previous engine and we struggled really bad with surge, spiking in the higher gears and not boosting to the max/boost tailing of in the lower gears. I had to compromise on the level of boost that could be run to keep the car driveable.
Now Ive got a perfectly tailored boost curve that self adjusts in different gears so 1st will see more duty cycle than 5th for example meaning that every gear I got identical boost that comes in quicker doesn't spike and holds for longer with only a teensie bit of surge in the higher gears for an insignificant amount of time just before 4k. Once I fit a second dump valve that will also be resolved as currently the single unit is not shifting enough air on dump either. Sounds more like a bang instead of the conventional dump valve woosh.
Just for completeness I used the aby dipstick because I thought it was a better match for aby sump in use
There is a hole in the block Andyp blanked off I'll find a pic
^^^^ Interesting info Jamo, reason I went diesel dipstick setup is I was baseing it on the theory that I was wanting oil upto a certain height down from the block. Rather than an amount up from the bottom. Im starting think however that the height the dipstick looses oil level by also co incides with the thickness of my mains girdle.
Its really bugging me at the moment as I want to make sure it has enough oil before thrashing it but have no real certain way of knowing if the dipstick is reading correct for application now.
I may have to dump the almost fresh oil and fill from fresh correctly metered with a jug and then make my own marks on the dipstick.
@PRJ, interesting I always thought it was 5v as this is where the zeitronix unit flatlines.
It probably flatlines there due to a 0-5V ADC. Fit a divider there to see higher values. Meaning for example a 0.5x divider, so 5V would be shown as 2.5V
As for boost control on stock management I went the 4bar vmap route on the previous engine and we struggled really bad with surge, spiking in the higher gears and not boosting to the max/boost tailing of in the lower gears. I had to compromise on the level of boost that could be run to keep the car driveable.
In my experience, and I've mapped 30+ cars on 4 bar map sensors, this is due to incorrect duty cycle setup and a few other things.
Now Ive got a perfectly tailored boost curve that self adjusts in different gears so 1st will see more duty cycle than 5th for example meaning that every gear I got identical boost that comes in quicker doesn't spike and holds for longer with only a teensie bit of surge in the higher gears for an insignificant amount of time just before 4k.
All down to mapping. No issues having similar boost between gears for me, as long as base WGDC is set right for every given RPM. The PID controller takes care of the rest.
Tested with GT35R at 650+ PS.
You might as well dump stock ECU management. Rather have a standalone, than stock management with Alpha-N fuelling due to saturated MAF and no boost control.
Anyway, I am polluting your thread. I'm sorry, let's get on with it
^^^^ Interesting info Jamo, reason I went diesel dipstick setup is I was baseing it on the theory that I was wanting oil upto a certain height down from the block. Rather than an amount up from the bottom. Im starting think however that the height the dipstick looses oil level by also co incides with the thickness of my mains girdle.
Its really bugging me at the moment as I want to make sure it has enough oil before thrashing it but have no real certain way of knowing if the dipstick is reading correct for application now.
I may have to dump the almost fresh oil and fill from fresh correctly metered with a jug and then make my own marks on the dipstick.
I used the ADU dipstick poured 4.5 liter in (as per original ADU when oil filter is anstalled)
I let it run for 1 min->let it off for a bit so the oil accumulates down and then marked at this level the dipstick. So that i know where the 4.5 liters are with the filter full.then made another line 3mm up and 3mm down. At the lower line the oil in is approx 4 liters and up approx 4.8.
These newer marks are a lot higher than the original one.
Don't worry its all information that's of use to someone at the end of the day.
I think the biggest advantage I found running an aftermarket boost controller was its ease in achieving stability. With the advantage that you assist the spring by pressurising the top chamber of the wastegate allowing the valve to stay shut for longer for a more aggressive attack without the need to spike the boost. However for all I know stock n75 can be plumbed and reconfigured this way too?
The head/cam configuration I run seems to have always been a bit strange in the way the boost needs to be controlled, we tried and tried on the original engine and anything over 1.6bar it didn't want to play getting full boost at part throttle surging harshly in all gears over 3rd making the car undriveable. We gave up in the end fitted an aftermarket controller and never looked back.
As for going aftermarket managementay the engine has always been build to go that route on the long run but I don't have 2k to put on the table for my desired ecu especially when what I got that costs nothing in effect works. At the end of the day we've played safe and kept to 1.7bar so I can thrash it all day long without worrying whether the fueling is not enough, EGT'S going too high, unexpected knock from a bad batch of fuel etc. I don't have time to drive around staring at gauges all the time to make sure everything is ok I like to get in a car and drive it.
For that matter likewise if I got enough time to look at gauges on the track I ain't going fast enough
@Billman. Was that 4.5ltrs ontop of the oil already in the cooler and filter or inclusive?
Don't worry its all information that's of use to someone at the end of the day.
I think the biggest advantage I found running an aftermarket boost controller was its ease in achieving stability. With the advantage that you assist the spring by pressurising the top chamber of the wastegate allowing the valve to stay shut for longer for a more aggressive attack without the need to spike the boost. However for all I know stock n75 can be plumbed and reconfigured this way too?
Yea, you can plumb it in that way.
The head/cam configuration I run seems to have always been a bit strange in the way the boost needs to be controlled, we tried and tried on the original engine and anything over 1.6bar it didn't want to play getting full boost at part throttle surging harshly in all gears over 3rd making the car undriveable. We gave up in the end fitted an aftermarket controller and never looked back.
Well, that just sounds like wrong mapping to me. But I guess anyone can be smart on the internet, if I ever get the chance to, I'd happily give it a shot
At the end of the day we've played safe and kept to 1.7bar so I can thrash it all day long without worrying whether the fueling is not enough, EGT'S going too high, unexpected knock from a bad batch of fuel etc. I don't have time to drive around staring at gauges all the time to make sure everything is ok I like to get in a car and drive it.
That's why it's a good idea to have the full range MAF, so you don't have to worry about those things... Oh well.
Although, you have plenty of power on tap anyway with the current config.
I don't really like AAN with that power myself, even on a stroker. The shell it usually sits in is restricting with not very good handling and the car gets a huge difference between off boost and on boost with aggressive cams.... the RS4 was the best thing I've ever bought... it's like you've got more of everything absolutely everywhere, except the rear legroom.
In the end you've put in a huge amount of effort, and I hope that everything stays together and runs well for a long time to come.
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