LBZ: Questions on twins

[BHoward6.6]

I installed a S475 over a GT4094VA.
My boost at WOT is about 40 till the TC locks, then it goes to about 50.
The S475 boost is 15~20.
Other mods.

ARP Headstuds.
ARP Rocker arm Shaft bolts.
RDL's EGR Delete pipe.
3" IC Tube.
PPE billet fuel pick up.
AIRDOG 2 DF-165.
MBRP XP Series 5 in. Exhaust.
RDL CastFlow Manifolds & PPE Up pipes.
Blankets on up-pipes.
Mike L trans.

Do these #'s sound about right?
I will have my drive press gauge hooked up Fri., With twins what is the norm drive press?
Any tunning tips or tricks?
BOV's?

 

[cafryer]

What does your fuel system have done to it

 

[BHoward6.6]

Just the Air-Dog, Stock sticks and CP3.
On my DD tune (2700pw) it holds rail press.
On the big tune (3200pw) it is about 3k under des.

 

[bullfrogjohnson]

That 475 is gonna be in its sweet spot around 32psi. Loosen up on your wastegate and let the 475 do some more work. It can also be in the tuning with the gt40 being a vvt.

 

[cafryer]

I dont know on the lbz but with stock fueling it seems about right to me. Put more fuel to it and you will drive them harder and you will see more psi.

 

[BHoward6.6]

These #'s are with my DD tune, 120mm3, 2700pw. 29* timing.

 

[BLKLMM]

Seems about right....my 80 was between15-20lbs too:thumb:
Who's tuning??

 

[BHoward6.6]

A cross between Nick's GT4094VA tune and mine.

 

[BHoward6.6]

Pics

 

[LBZrcks]

Have you logged to see if the vanes are opening up?

 

[BHoward6.6]

Have you logged to see if the vanes are opening up?

Yep, With your tune at WOT they go to 0%. :thumb:

 

[BHoward6.6]

Installed the drive press gauge.
Mostly stays around 1 to 1, till WOT, then it's 75~80psi D.P. for 50psi boost.

 

[RoboF16]

...75~80psi D.P. for 50psi boost.

Sounds high to me for twins at that boost level, but I'm no expert.

 

[Harbin_22]

I get about 58# boost to 75# drive. That is a stock turbo with a 475. That is convertor locked and 4th gear and up. I am seeing around 20-25# on the 475 depending on rpm.

 

[Harbin_22]

I have 40% injectors too. That is not my race tune but around 2300 pw. Haven't done much testing on the race tune as I am scared :rofl:

 

[BHoward6.6]

Since installing the D.P. gauge, I tuned the vanes back to 0% at WOT and now the D.P. is 60psi at 50psi of boost.