RealQuick

iTrader: (14)

hit the dyno again (4th time with turbo setup)... made some modifications over the winter:

removed wastegate dump from downpipe to atmosphere
removed airfilter in lieu of a screen
added twin cutouts on my 2.5" dual exhaust just after where the single 3" DP splits
Aluminum DS
Street Slayer Twin Disc

2010 Camaro SS M6
Stock bottom end
AI 280cc Heads
Vengeance racing turbo cam (235/231 .6xx/.6xx 115lsa)
Ported LS3 Intake
NW102 TB
1000CC Injectors/ZL1 pump/ADM FPCM
Huron Speed single turbo kit with Precision 7675CEA
Alky Control w/100% meth
SLP under drive pulley
No cats
borla ATAK 2.5" exhaust
Tune via hptuners (me tuning)

RESULTS:
Had lots of issues, one being I think clutch slippage in the mid range, some break up in the high rpms, my cutouts stuck open, and I couldn't run under 13psi.

In the end, I made 817rwhp/758rwtq @16psi. I feel like it would have hit 850rwhp with no changes if it wasn't breaking up in the higher rpms.

So, even with the issues, I made 114rwhp more with the changes I made.

No knock... maybe spark issue, valvetrain issues? I dunno.

Duty cycle at 64%

Here is the graph showing this time vs last time at 16psi. Torque starts similar this time but drops... but rpm's carry better this time.

RealQuick

iTrader: (14)

Plotting boost vs rpm, and comparing last time at 16psi vs this time... boost was lazy today and didnt hit 16psi until the end of the run. I wonder if my boost controller is taking a dump.

stevieturbo

Could be tuning, controller, plumbing, wastegate etc etc. Anything relating to boost control really.

But there is a huge difference there, so something needs looked at if it was all configured the same and you expected boost to be the same.

RealQuick

iTrader: (14)

Yeah, I am gonna dig into it this week, see if I can figure it out.

RealQuick

iTrader: (14)

A couple more notes:

- boost controller in "off" mode wouldn't let me run off the spring (I couldn't get below 13psi where as I could rum 8psi before on spring).

- BOV didn't blast open at the end of the pulls

stevieturbo

BOV as long as not leaking, wont matter to boost.

If you're saying the exact same combo used to run a steady 8psi when running spring only, and now climbs to 13psi, that would suggest either a boost control plumbing leak, or the w/g not opening correctly.

To rule out the controller, just pipe direct to the gate bypassing the solenoid ( again this can vary though as no idea what plumbing config you have used )

RealQuick

iTrader: (14)

Steve, I agree. I am gonna bypass the controller and log gate only.

RealQuick

iTrader: (14)

The clutch was slipping on the dyno... a couple runs were aborted half way thru because the revs jumped fast. Supposedly the tires werent spinning, so i don't know. It's a street slayer billet twin (so a rps clutch setup). I wonder is boost was lazy because of that.

stoverz28

iTrader: (8)

Does the same thing happen with the cutouts closed? Wastegate could be falling behind with the higher flowing exhaust.

stevieturbo

Clutch slippage wouldnt affect spool, but obviously would affect power readings.

Likewise tyre slippage on the rollers.

RealQuick

iTrader: (14)

Clutch slippage = loss of engine load

The more the engine is loaded the faster the spool of the turbo right?

RealQuick

iTrader: (14)

I only made a coupler runs @13psi with the cutouts closed versus open... then the gates were stuck open the rest of the session. Ill double check tonight. I gained 46rwhp/7xrwtq between closed/open @ 13psi.

In theory, cutouts should reduce the spool time due to drop in back pressure post turbo.

RealQuick

iTrader: (14)

Captured some clutch slip I believe on the very first pull I made:

Notice the rpm/speed and where the vertical cursor is on the log.

You can see where boost dipped too.

stevieturbo

well yes, but it would be blatantly obvious there is a problem so you would stop trying to run it at load. Even more so if it was happening that early.