DanaliHD

iTrader: (5)

ok, latest news is: truck runs great under 6lbs boost. Made just over 450rwhp on a mustang dyno on 6lbs.

bad news is, it wouldn't hold over 6lbs boost. For some reason the backpressure at 6lbs boost is 30. hmmm

the turbo is a ITS GT80 with 1.15 a/r. 4" downpipe. Something is clearly not right. They are looking into it but not until after Jan 2 cause they are shutting down until then. In the mean time, anyone have any ideas on why it won't make boost and why the backpressure is so damn high?

Also, when they looked at the compressor maps for the turbo (which i found on the AU version of the innovative website since the US version is no longer, it appears that this turbo is NOT a good choice for my application. Precision recommended a GT4276 with 1.28 a/r. Thoughts?

for the record, all of this is WAY over my head. Clearly W2W will figure it out but I'm just curious to see what the general FI community thinks. I'm doing whatever they tell me regardless.

thunder550

iTrader: (70)

I dunno man....I'm running a PT76mm with a .96 a/r housing, and it works great so far. Starts to spool at about 2500 RPM, but runs out of steam (probably too much backpressure) at about 5500 or so. I had it on the dyno and made 575rwhp and 640rwtq at about 14 psi last weekend, with an unlocked converter, 13* of timing, a fat tune, and all 3" turbo-back piping. I think my setup is capable of 700+ if I get the bugs worked out...gonna try moving to a 4" DP and possibly a 5" exhaust to see if that removes the top-end restriction. When I open my cutout I gain about 2-3 psi, so I'm thinking that's the restriction on mine.

XLR8NSS

iTrader: (4)

After the 4" downpipe what is the rest of the exhaust setup?

DanaliHD

iTrader: (5)

no cats, stock 4" exhaust out of a duramax.

Casey2323

iTrader: (14)

whats the Hotpipes look like? small cross over pipe 2.5" with a stock manifold? and log header? ... Do you know what size wheel is in the turbo?... I am sure W2W isnt measureing backpresse after the turbo.. Its in the manifolds/hotpipes that feed the turbo... Does the camshaft have a ton of overlap in it?...or a stock manifold... whats the dyno sheet looks like? Also is your turbo a t4 flange....

DanaliHD

iTrader: (5)

it IS a 2.5" crossover pipe. Pass side manifold is in it's factory position, driver's side is flipped. No idea what size wheel is in the turbo, it's a ITS GT80 DBB 1.15 A/R(not a clue what that means, lol). Don't have the cam specs in front of me(i'm not at home), don't have a dyno sheet.

hmm, maybe I need more info for the questions to be answered correctly.

DanaliHD

iTrader: (5)

Ok, looks like it comes stock with a X trim and .96 a/r. Their site is down but if you google it and click on the cache you can see some of the info. I found this on another site:

GT80 X-Trim, the highest flowing T4 frame size on the market, holds the current drag-radial class record. Max flow up to 1030HP Ideal horsepower range is 800 –1000, comes standard with .96 T4 Tangential turbine housing. See options below for other turbine A/R’s. Suitable options are: · Super Duplex, Dual Ballbearing · R-trim turbine wheel, for ultimate back pressure reduction. · Polished Compressor Housing This Innovative GT Series turbo features; · ITS Big Shaft option for strength · ITS 10 bladed Turbine Wheel · Inconel for high EGT durability · Highest efficiency available · ITS’ unique Hydrodynamic Bearing system · 360 Degree Super Thrust · Redline balancing. All components meet rigorous quality control, each turbo is assembled by experienced turbo technicians, taking the utmost care to ensure Innovative’s exacting tolerances are met.


problem is, i bought it used from a guy on a turbo mustang site. I'll try to contact him to get more info.

doofus

I had a local "Tuner" originally tune my truck and he damn near destroyed it. I did all the work on it, all he did was the tune. It was so bad that the second guy I went to said he could explain to someone over the phone how to tune a vehicle and they would do a better job than him. Once I get my new additions dialed in I'm going back for round two. Sucks to pay someone to do a job and they screw it up. Good luck!!

Spoolin

iTrader: (8)

When it would boost to 6psi how fast would it spool up?
Did they pull the hot side apart and see if there's anything there?
This is a shot in the dark as I don't know if this is possible on gas engines but if it was run rich for too long is there a possibility of build-up on the hot side? I remember having to clean out the exhaust on a Medium speed Detroit Diesel because of build up in the exhaust was 1/8th of an inch thick and was restricting the exhaust. Again no clue as to whether this much carbon build up is possible on gas engines.
In any case you should pull the turbo and have it refurbished...maybe they'll find the bearings shot.

DanaliHD

iTrader: (5)

yeah, i'm considering having them pull it apart when they get back into the shop after the holidays. BUT, Jesse from w2w spoke to precision today and they say that turbo is just not properly fit for my application. They recommended a 4276 with 1.28 a/r. Pretty cheap to buy brand new too. not sure I wanna spend the few hundred or whatever it costs to rebuild my current turbo if it's not gonna work efficiently anyway. ya know

also, someone on tech suggested that maybe the restriction is on the other end of things. maybe the intercooler. This reminded me that a year ago when the truck first got to dez from ny the intercooler was full of water. Not sure how that happens but maybe it happened again. If so, seems like that would cause a HUGE restriction. hmmmmmm