Been chasing low power issues since my combo has been together and someone suggested maybe one of my turbos is defective. I do occasionally get a little burning oil at idle and spooling seems slower than it should be. What can be wrong?

 

Bad turbo?
Bad/no tune?
Bad fuel system?

The list is endless..
Data logs?
Details on the build?
A lot more info needed to avoid the "20 questions" game.

 

Cat has been running street/track for months now, runs very well, on track pulls afr is between 11.2/11.6. peak timing of 22 degrees on E 85, duty cycle barely his 50%. Its a 427 lsx 9.7/1 motor. Twin Borg 76/82mm. Everything feels normal, doesent lay down in the middle of a run or anything, just doesent make the power it should and it seems to spool much slower then it should

 

I'm installing a back pressure sensor today to get some readings on that as well

 

Turbos are very simple items really.

If the shaft is free to spin, not excessive free play etc and no obvious visible damage, then chances are it is fine.

You're saying it's burning oil at idle....and you have twins. So can you pinpoint it to a single unit ? Are there visible traces of oil on the turbine wheel or housing ?

Oil drains all good ?

 

Definitely check for how free it spins. That's how I found mine was messed up.

 

Or best option ( not cheapest ) hook up speed sensors to both units and then you'll see what both are doing.

 

Sure there isn't a massive leak in the intake system somewhere?

Andrew

 

I did a smoke test on the exhaust and a pressure test on the cold side, both came out good, I haven't pulled the turbos apart to look for burnt oil, oil drains are-10 with 45 degree fittings on both ends and steady downward run. I did a few pulls on the street today up to 25 psi, blew the tires off it but I wanted the data, when I was in the 10-15 psi range my BP was 20-30 psi and held fairly steady as boost caught up. It's not great but I don't think that's worth several hundred hp

 

So you applied boost pressure to the compressor cover, through the inlet, all the way through to the engine/throttle body/intake manifold? How much pressure did you use? I am sure you found some small leaks doing this.

 

Only like 5 psi, I forgot the o rings on my bov's actually, ran for a year like that!

 

Data logs?
Tune file?
Inj size?

 

220 low impedance, I'm out of town at the moment. I've had several people look at them and they saw no smoking guns

 

Have you been to the track with this set up?

 

Yes, several times. 5.58/128.5 best pass so far. Think my 60 was 1.35 and made peak boost of 26 psi. Car weighs 4150 with me it

 

So that's about 1368hp.... How much power "should" it be making?

 

14-1500 at the tire is what everyone is expecting