[Chris1337]

Originally Posted by ap485

It still on the car but will be for sale once I get new one.

Bouta say you got a turbo farm or something haha

[timmv98]

Hey Alex,

Mind giving us an update? Were you able to achieve successful boost control with Speedtechs external wastegate turbo kit?

[tqylor]

The power gap between n54's and n55's are definitely closing!

[wheela]

OP, looks like you haven't logged on since shortly after your last post, but if you see this, how did you test holding your wastegate open?

I'm not getting there with the stage 3 head porting explanation for the overboost. The DME is load based, so it will calculate an air flow target and try to acheive it. With your head, you'll get more flow per psi, but your DME will see the extra flow and use the throttle plate (and/or boost target) to keep air mass entering the engine on target - regardless of actual boost. So with the right mass of air into the engine, you'll have what the DME expects for exhaust flow out of the engine. So your wastegate should be keeping up.

I could understand some boost creep at very high power levels, but with 0% WGDC% at mid-rpm's, I have a tough time understanding this level of boost creep on a stage 3 turbo whose wastegate should flow exhaust waaay better that the stock unit.

I know you tested your wategate, but it really sounds like your wategate isn't opening. I can't imagine this would have been overlooked, but did your bigboost kit have a traditional wastegate actuator (ie normally closed, opened with boost pressure)? As I'm sure you know, the oem boost control uses a normally open vacuum actuated wastegate. So unless you were plumbed for, and running an external boost controller, this could explain your WGDC% going to zero, as the DME is trying to open the wastegate. Only with a conventional wastegate connected to the stadard oem boost control plumbing, it would still be closed with 0% WGDC. It wouldn't even open at spring pressure, as your boost solenoid at 0% duty cycle would vent the WG actuator to atmosphere vs. pressurize it with boost from the manifold. The only way it would open is if exhaust pressure pushes it open.

Anyways, just sharing my thoughts on the matter. If you're still around, sweet engine build! I hope you got your issue sorted.

[zw335i]

setups looking great sofar, can't wait for the final result!

[BimmerHausPerformance]

Sub'd

[ap485]

Originally Posted by timmv98

Hey Alex,

Mind giving us an update? Were you able to achieve successful boost control with Speedtechs external wastegate turbo kit?

Yes, external wastegate is the way to go on pwg cars with big turbo.

[ap485]

Originally Posted by wheela

OP, looks like you haven't logged on since shortly after your last post, but if you see this, how did you test holding your wastegate open?

I'm not getting there with the stage 3 head porting explanation for the overboost. The DME is load based, so it will calculate an air flow target and try to acheive it. With your head, you'll get more flow per psi, but your DME will see the extra flow and use the throttle plate (and/or boost target) to keep air mass entering the engine on target - regardless of actual boost. So with the right mass of air into the engine, you'll have what the DME expects for exhaust flow out of the engine. So your wastegate should be keeping up.

I could understand some boost creep at very high power levels, but with 0% WGDC% at mid-rpm's, I have a tough time understanding this level of boost creep on a stage 3 turbo whose wastegate should flow exhaust waaay better that the stock unit.

I know you tested your wategate, but it really sounds like your wategate isn't opening. I can't imagine this would have been overlooked, but did your bigboost kit have a traditional wastegate actuator (ie normally closed, opened with boost pressure)? As I'm sure you know, the oem boost control uses a normally open vacuum actuated wastegate. So unless you were plumbed for, and running an external boost controller, this could explain your WGDC% going to zero, as the DME is trying to open the wastegate. Only with a conventional wastegate connected to the stadard oem boost control plumbing, it would still be closed with 0% WGDC. It wouldn't even open at spring pressure, as your boost solenoid at 0% duty cycle would vent the way it would open is if exhaust pressure pushes it open.

Anyways, just sharing my thoughts on the matter. If you're still around, sweet engine build! I hope you got your issue sorted.

I understand how the oem wastegate works and I agree with your explanation but that was over two years ago and I barely remembered how it was tested. However, the shop tested as Bigboost requested and they mentioned that the internal wastegate was max out so, they provided a fix but it didnÂ’t work. Bigboost concluded that the only solution was to go external wastegate in my case.

[wheela]

Thanks for responding, I hope that speedtech kit is working well for you!

[ap485]

Originally Posted by wheela

Thanks for responding, I hope that speedtech kit is working well for you!

It’s a really good kit. I have had zero issues since installed. The problem now is traction. I’m about to pull trigger on a LSD.

[Dinocrest]

Hey Alex, Glad to hear the car is running well!

I was wondering how did the trans work out for you. Specifically in daily drivability.

And do you daily the car or is it at least possible to daily the car like this?