eviltwin_1987

iTrader: (18)

My LS2 TC78 spools really fast. Im guessing your tune needs work?

JoeNova

Is your wastegate cracking open as boost is building? Check for exhaust leaks and boost leaks. I doubt your tune is bad enough to be loosing 1000 rpm.

Ryans99ls1

iTrader: (16)

Put a manual boost controller on it even if you arent turning it up. It will help keep the wastegate from cracking open early.

BMF_Racing

iTrader: (6)

Like others said, assuming tune is remotely close, there must be a hotside leak or the WG is cracking open. Def way overkill on the 3", that is worth a few 100 rpm. Just to give you an idea, we have a lower comp ratio 5.3 with a gt4788 on it and we see 5psi at 3400 with a 2" cross over. With a 6.0L you should be in this same area if not lower.

Good luck.

awd-rwd racer

iTrader: (16)

No hotside leaks that i see or hear. I dont have a boost controller. Just running of my tial 44mm wastegate for now...would a regular ball n spring mbc help keep the wastegate shut? Or is there a specific type i should look for?

MUSTANGBRKR02

iTrader: (91)

That should do fine. Could stack a few washers under the spring to to increase the tension. Be a cheaper option.

yenkomike

iTrader: (2)

I whould start with the easy stuff. make sure it has NO exaust leaks . make sure your wastegate is closing and sealing all the way . get your ve table dialed in . I whould make 100% sure of these areas first and go from there.

69-chvl

iTrader: (11)

I once disconnected the boost reference hose to the w/g for testing purposes and I was suprised how much faster boost came in and overal general engine response was.

rotary1307cc

iTrader: (5)

I would look at your exhaust post turbo first of all

awd-rwd racer

iTrader: (16)

post turbo i have 3" pipe to a magnaflow 3 chamber muffler. thats it.

MUSTANGBRKR02

iTrader: (91)

Try removing that muffler.

awd-rwd racer

iTrader: (16)

id rather not if i dont have to, its already loud as it is...

Fondle

iTrader: (4)

your merge is way to big! i am running a 5.3 with ported and milled 317's, 224/224 602/602 115+4 turbo cam, and a tc78 with a .96 ar, BUT i have 2.25" crossover from the manifolds to a 2.5" merge up to the flange. i get full boost around 2900-3000, running 12psi right now, made 700

Also, 3" is pretty small for the exhaust, especially for a 6.0 i would think. i custom ordered mine with a 3.5 v band , and i have 3.5" all the way to the rear axle with a cutout and a bullet muffler.

Johnv

Your Hot side pipes are on the big side at 3", but your exhaust isn't helping you either, single 3" is on the small side and chambered mufflers are way too restrictive for a turbo car.
Pull the mufler and replace it with a straight thru type and i'll bet you'll see a big difference.

I would do that, and tweek the tune before jumping into rebuilding the cross over pipes.