V-seriesTech

iTrader: (5)

100% self inflicted. Pretty sure it was either me that changed them like 6 years ago. Race Part Solutions is next day airing 2 for today, even tho just one was pinched. Gonna try and test today and hit up track.

Perhaps blowing through the inside since it is folded over and slightly pulled away ? I dunno man.

New one on the way regardless, gonna throw them on and see what happens.

dburt86

iTrader: (2)

So what are we thinking here? just trying to wrap my head around this...

the wastegate is letting too much exhuast flow bypass for one turbo, effectively making it not spin fast or at all during idle

And because one turbo is moving much slower then the other, and they share a common intercooler, the faster turbo is pushing air out of the slower turbo?

stevieturbo

The wastage cannot be leaking at idle because of this, as the spring would be holding it shut regardless.

oscs

iTrader: (19)

I'm willing to bet it was never blowing air out of the other turbo. A check of the MAP would verify vacuum at idle making it highly unlikely that the turbos were creating any positive pressure.

chuntington101

Or the OP is running a killer anti-lag startergy! Lol

coltboostin

1) I've seen this happen on smaller twin set ups, especially ball bearing with a surge cover. Big motors can get some turbos past the choke line at idle or part throttle. If its making boost and there are no issues in the logs, I would not worry about it, or get a lighter BOV spring.

2) you may ad well not run an intercooler as those little cores mounted at that angle are going to do dog dick. Hell, it may just act as a heat sink for the radiator.

3) do you have anything shrouded up there? If not i'd be shocked if the car did not run hot in most any conditions.

Good luck!

coltboostin

Think about what your saying. Your saying a reading from BEHIND the throttle plate dictates what is happening INFRONT of it?

I can tell you with 100% certainty there is a possibility with the right coby of factors the shaft speed could be left of the surge line near idle, which would cause air to basically continually dump out of the surge ports in the cover. I have seen 3 cars do this in person, including my personal car at a high idle.

That being said I am not sure of the OP's combo to comment if this could in fact be HIS issue. But if it Rips, I wouldnt say there is an issue anyways

oscs

iTrader: (19)

I know what I said read it again and try to apply a little common sense. A motor creating proper vacuum (MAP sensor verified like I said) should be consuming at idle. I've never seen a PROPERLY setup twin turbo application not be able to consume what little air the turbos are pushing. This isn't a 500ci BBC with 40mm turbines.

coltboostin

Yes, of course it will be consuming something-but the vacuum is just showing a restriction-a differentiation of pressure from the 1 bar outside of the motor. Knowing the motor is vacuum alone tells you nothing about the relative air pressure OUTSIDE of the intake manifold.

Simple fact-if the shaft speed is allowing the compressor to move more CFM that the motor needs to sip (as thats all its doing at idle under vacuum) than there will be more than 1 atmosphere of pressure in the pipe. It has to go somewhere. On some cars- the BOV hangs open and air flows OUT at idle. Same situation, but in this case I assume the BOV is not open.

Its speculation on this car, but I have seen it before in person. Again, on my personal car at a high idle.

SethU

With nearly any turbo set-up... if you were to open the BOV at idle, air will come out. That's literally positive pressure in the charge pipe, albeit likely only several inches of H2O.

Not likely enough to push back through another spinning compressor wheel, especially enough to feel... But, who knows. Stranger things have happened.

What's the latest with this deal?

coltboostin

Assuming you mean the BOV?

SethU

Hahaha... yes. Good catch. Fixed.

V-seriesTech

iTrader: (5)

I ended up popping the motor this past Friday night at the track.

Good times, good times. In it's downtime I will inspect what I can with both turbos.

oscs

iTrader: (19)

Damn the ******* blows. What happened?

V-seriesTech

iTrader: (5)

Excessive cylinder pressure, lifted head on driver side, pushed water through LS9 gaskets like I haven't seen before, that side is actually fine, the passenger side, the water jacket collapsed on #2 cylinder(LS2 block), happened at end of run right when i lifted, so damage wasn't worse than the 1 bad cylinder, which did a small number on my combustion chamber of the one head. Some material in the intake but minimal.

Best case scenario is 1 new block, 1 new piston, 1 new rod. Everything in the engine rotates fine...pulling motor today.

Heres the pass....and yes that is 5th gear. To save time, setup is:
twin 67s, e85,tfs 235s, ZR1 tr6060, 25.9" tire, tilton triple carbon lightweight clutch(14.7lbs w/flywheel),3.42 gears. RPM shifts once I put the purse down was 7100rpms. Car weighs 3050, and 3250 with me in it. Yes, I fucked the launch up. It is a very unique clutch, it is so light, the car revs so fast, and also decels quick so by the time I "blipped the throttle" to launch it, it had already dropped throttle, gained traction, and stalled. My fault, new setup.