I just got the car tuned after installing my stage III Incon T system. I was very disappointed to see that it only mad 430 rwhp and 400 rwtq with 13 psi. I know it can do better than that because when it was still a 6 speed, it was making 450 rwhp just the way it sat. I realize I am losing power through the auto now and even more with a big 4k stall, but at 13 psi, that should more than make up for it. Here is are some things to consider:

1) I opted to put the smaller 8 psi wastegate actuators on for now because I though that running 14 psi on the low side all the time might be a little much for the street. On the dyno graph, the car spike to 13.5 psi for a second, but then falls right to 10 psi and holds that til the end. I'm thinking that maybe the actuator springs are too weak to hold the flapper valve in the wastegate and it is opening more than it should under high pressure and causing some boost to bleed off.

2) That stall is a lock-up 4k from Precision. I got it from the guy who I got the auto trans from and he said it was a fairly tight converter and would be good for a boosted car, but after driving it, I'm not so sure if it is since it seems to take even longer for the car to really get going (not including turbo spool time).

3) I was considering running big open down pipes at the beginning, but changed my mind because I though they might be too loud. I went ahead and put on the 2.5" downpipe to Y to dump setup that the guy had made for it a while back and put some cutouts on the front to help it out. That 2.5" setup may be choking the turbos because when I uncapped the cutouts, I saw almost no extra gains at all.

4) As I was driving it home from the tuning shop, I realized that I had no AC blowing out of the top vents. This was a serious issue to me since it's been hotter than hell here this summer and the way I see it, I sweat enough at work everyday, I'll be damned if I'm gonna pour sweat in my nice car! Anyway, I did some research on here and found that it was a vacuum line for the HVAC that had gotten disconnected from the manifold somehow. I plugged it back in and sure enough, the problem was fix. HOWEVER, the new problem is that when that vacuum line is connected, it makes the car idle at about 2,300 rpm. I'm wondering if that is because it was all tuned while it had the vacuum leak and now I'm wondering if that vacuum leak also affects my turbos and vacuum wastgate actuators as well.

So far, that's about all I got wrong with it so all in all, that's not too bad for such a big project where so many things have to be taken out, re-installed, re-wired, etc. I just need to get these bugs all straightened out.

 

Vacuum leak would more than likely **** with all that. Especially if there was a vacuum leak and it was tuned to idle like that. When you go into boost your manifold is in boost and that leak is going to, well, leak. Thats probably why your boost is dropping off and your turbos are only able to keep up with the leak to 10psi.

 

Something isnt right if you're making NA numbers with a turbo...

A stahl should not rob 150rwhp. Get that vac leak sorted out and double check everything else why youre at it for good measure. IC pipes, hotside connections, etc.

 

It registers that is keeping at least that much boost but there has to be a leak somewhere I think.

 

That vacuum line port, is the smallest one in the intake and due to it's location is almost impossible to notice unless you are looking for it. If the turbos are working real hard and managing 10 psi despite the leak, the charge temps are probably pretty high. But even with all that, you should be making more power at 10 psi. It is likely a combination of things. Is the converter locking on the dyno for sure? What are you seeing in RPM drop when you shift 2nd to 3rd at WOT at whatever boost you are making and at what RPM is the shift?

 

Today when I drove it around and made a few hard street blasts, it splashed some oil up into the motor compartment. I looked like the oil was splashing out of the BOV so now I think that oil is somehow making it's way into the intake side. The turbos smoke like a bastard too, even with my big scavenge pump. The turbos were rebuilt not too long ago, but I'm starting to fear that these turbos are bad. I hope I don't have a cracked head or plown head gasket, but the car runs great cruisnig around. I don't know, Im just praying that somethig isn't hooked up right and that's all.

 

I found a small leak in the passenger side turbo line, but it's the line going to the turbo, not the return to the scavenge pump. Could that still somehow interrupt the proper flow of the system and actually make oil puddle up in the turbo like it's doing? I called a local turbo specialist shop that deals with a lot of Garrett turbos and the guy told me that the bad news was that if a ball bearing turbo like mine has a seal or bearing issue, I will have to find a special kind of shop that can even start to rebuild it. Apparently there is a lot more to the ball bearing turbos than conventional ones. The good news, he said, was that just because there is some oil making its way back into the intake doesn't necessarily mean that it has a bad seal. He said if something isn't right with the oiling setup, which obviously is the case with mine, then it will come out like that if it really starts to fill up the center of the housing. Also, the fact that the car only really smokes for a bit once started, and then only every now and then after that, it's probably not a seal issue, because he said if it were, it would be smoking really bad all the time, no matter what. He said start with the cheapest and most practical solution, checking and fixing the oiling setup, and go from there, and only send it off for a rebuild if all else fails.

He also said that the boost issue might be due to the actuators on the older housings sticking and not closing all the way. How can I help insure that those move smoothly?

I will have to double check all that when I get these oiling issue straightened out. The stall acts like it has a mind of its own to me though. It feels as if it locks and unlocks randomly while cruising and its hard to tell under WOT.

 

1. oil in the intake will cause detonation, which will cause the pcm to pull timing.
2. If your still running a MAF oil on the maf wires really hurts horsepower, I don't know why or how but I know from experience. So all that oil on the intake piping isn't helping.
3. Are you sure the scavange pump is turning on and staying on? I had mine triggered by the pcm fuel pump wire and the voltage from the wire wasn't enough to keep the relay tripped 100% of the time.

 

Well I have it wired up to just come on and stay on whenever the key is turned to the ON position, whether the car is actually running or not. I did it that way so that I could turn it on before and after the car was started to insure that all the excess oil was out of the turbos. It should be staying on the whole time, but I haven't actually gotten under there and got right up on it to see while the car was running.

 

Rereading the thread, turbos don't really have seals like you might think, it's pretty easy to get oil into the compressor, I think it's more of a oil scavange problem. Once you get the oiling issue straightened out you really need to be able to datalog the car. When you go into boost, you can check your timing, intake temps, etc. That will give you a better idea of what is going on.

First thing to check is to make sure the oil drains from the turbo have a clear path to the scavange pump.

 

Yup, already did that. I had all new lines made for the pump and made sure that they ran in a straight, clear path right to the pump. I was having this issue before I got this new pump and I though it was just due to the old pump being old and the seal going out, but obviously there is more going on here than that. The only thing that remains unfixed is that line going to the turbo, but I figured that would make it starve for oil before it would make it puddle up.

 

I decided to further investigate these oiling issues tonight so I went out and jacked up the car and took some pics and a video of the underside while the car was running. I found some interesting and new things going on.

Here is the scavenge pump set as level the turbos as possible.




Here is the underside of the driver side turbo. There is a little oil collected around the return fitting and on the bottom so it's hard to pinpoint a leak here.


Here is the passenger side turbo. I wrapped some shop towels around the lines to try and find the source of the leak and this side of the oil line that goes between the 2 turbos came up soaked. The fitting on the return line also had a little oil collected on it too, but that could just be from splashing up.


The return line going back into the oil pan appears to also has some oil collected on it.


Now here is a video of the car running from the bottom side. The only leak that is blatantly apparent is between the turbo and the down-pipe. This means 2 things, there has to be a slight exhaust leak here now letting that oil come through, and there is so much oil making its way back into the exhaust side that its actually dripping out.



It looks like I have leaks from all sorts of fittings and gaskets so I don't know what the hell is going on but I'm getting frustrated.

 

I was trying to eliminate the catch cans completely with the strong Turbowerks pump. Obviously something more needs to be changed, maybe with the PCV system, or I may have to put the catch cans back on. Who else out there has had the Incon kit and eliminated the catch cans from the setup, the right way that is.

 

Just A note my turbos kept leaking alot like yours and it turns out the 90 degree return fittings were causing my issue, i changed my fitting to straight fitting and looped the lines around in a nice level drop and all my problems went away!

 

Would I need to eliminate the 90 fittings from in front of the pump as well as off the turbos themselves?

 

Today I took the exhaust cutout caps off to see if there was oil in both sides or just one, and it was in both. This leads me to bieve that it is in fact an oiling issue rather than a blown turbo. The chances of both turbos being bad after only about 2k miles on them seems unlikely. I think all that oil was coming out of the passenger side in the first time because of the way I had the car jacked up. Sitting level, it's not near as bad. I may just put the catch cans back on and go from there.

 

I just noticed a new oil problem. When my car is at idle, the oil pressure gauge drops to nearly zero. When I rev it a bit or drive it, it stays at around 40 psi. What could be causing that? Could the scavenge pump maybe not be butting oil back into the motor fast enough? The oil pressure was never an issue before the turbo install so I'm thinking it's probably not in the motor itself. What causes it to rise back up at higher rpm though?

 

Did you add more oil in to account for the extra capacity?

 

Well, the dipstick shows that it's on regular operating level when running so I guess I put enough in there.

 

Any updates to this?