wouldnt an mbc in parallel with the N75 solve this problem?
are you talking about the turbine housing?How much is machined out? Do they do it on a normal lathe with a boring bar etc? And where exactly from on the turbo?
Who mapped it? I'd suggest if it's overboosting it's a mapping issue.
You would get a better response with a yellow spring..
25 psi seems high for 215 g/s ?
What were the results on the dyno?
I wont mention rods...
When you say over boost, is it climbing to 25psi. Fluttering and then settling at say 21psi tapering down? I only ask as I've been experimenting with my hybrid as I was getting the same thing but climbing to 27psi then settling at 23psi. I've been playing with the PID maps specifically the D by increasing it, which in essence makes larger compensations for over shoots on the n75 to get it back to we're it should be to controll the n75 and ultimately the actuator. Having done this it's significantly reduced the overshoot and flutter, my point being I'm convinced the n75 is just not reacting quick enough and hence the over shoot, I'd be inclined to side with prawn and say its a mapping issue. Surely 1.7bar is high for a stage 1 stock k04 remap anyway?
@ Rich196, 1.7bar on a stage one is just not right! I'll take it back as at those boost levels all you're doing is pushing loads of hot air and that just isn't going to last long(turbo or even rods) Was your car mapped on a rolling road?
obviously taking maf/.8 it would be around 315bhp yes.. And no surge running at about 19psi. I'm sure if I can get actual boost up with requested I'll hopefully be at 320bhp . I have a strange issue i'm looking into as me load seems to be pegged at 191.7 which I think is also holding it back as I'm requesting 200-210 which it should easily meet. I'm also sure I don't have a boost leak. And looking at the n75 duty cycle think that they can be improved to sort this out. I'll have a play tomorrow to find outSo is that hybrid making around 315bhp? And thats not even with a largeport head or ragging the nuts out of the hybrid?
So with a largeport head and more map playing whats the most you think the hybrid of yours would achieve?
obviously taking maf/.8 it would be around 315bhp yes.. And no surge running at about 19psi. I'm sure if I can get actual boost up with requested I'll hopefully be at 320bhp . I have a strange issue i'm looking into as me load seems to be pegged at 191.7 which I think is also holding it back as I'm requesting 200-210 which it should easily meet. I'm also sure I don't have a boost leak. And looking at the n75 duty cycle think that they can be improved to sort this out. I'll have a play tomorrow to find out
Load isn't pegged at 191, it's just that for logging purposes it is stored as an 8 bit number where FF=191.
Rick
Beachbuggy thats really awesome work. i was searching the net for how to disassemble a K03s turbo and came across this and learnt so much more. i was looking to rebuild the K03s myself to standard spec to learn and not pay rediculous fee's. but you have got me thinking now.
so the compressor housing is not big enough to take machining for a larger wheel, but the the exhaust turbine can be upsized? is that right? im from camberley!
but repairable?
Spec wise the car is a hybrid k04, xs power manifold, blue flame dp and cat, B5 tip, 550 injectors, Ie rods, Small port head. ME7 BAM ecu upgrade.
As you can see I have either a boost leak or the N75 maps can be tweaked to make actual meet requested.
Here we go, the logging software does fats as well so I have included a picture of that as well., I have no idea whats good or whats not.
Its an Audi S3 AWD 6 speed manual
overall gearing, which includes the gearbox, gear used, wheel/tyre size will all effect the times when comparing different cars...