600+hp

iTrader: (5)

What's your fix ?

I spent a couple of days researching and reading up on the subject and all it did is making me even more discouraged.
Seems like there are as many explanations as there are suggestions as to how to fix it but no definitive remedy or remedies.

The car has been 100% professionally built, it has the following :

_BR stroker and stage 3 head
_AMS 3076r turbo kit w/ Tial BOV and wastegate
_AMS Alky kit
_HKS 272/272
_Profec 2B boost controller
_BR IC and associated piping
_BR turboback exhaust w/ custom Random tech cat
_HKS DLI
_780cc AMS injectors
_AEM and tuned by Martin of AMS

Currently I can't run anymore than 20lbs without it surging very badly in gear 2-5, I have not been getting on it in first gear so I can't say.
When I had the stock motor w/ the same turbo kit and supporting mods, I was able to run 25lbs or so without surging. It only comes on as you get closer to 27-28lbs.

Here are some of the suggestions on the fixes,

_Porting of compressor cover, very limited success from what I've read so far. This is what AMS suggest. Another problem is last time I checked w/ precision turbo they don't offer one for the 3076r.
_bigger camshaft on intake side
_change wastegate spring...softer, stiffer ? explation goes both way
_Bigger intake tubing
_Etc...

Do I have to switch to a different turbo altogether ?

Maybe I'm cursed by the mods GOD

A418t81

iTrader: (5)

Almost every 3076 that I see has the surge ported comp cover on it. Your AMS setup does not? My 35R from AMS has the surge ports as well (instead of the drilled E cover).

600+hp

iTrader: (5)

No and I called precision turbo and was told none is available.
Also disappointed w/ the result of my stroker. The improvement in spool is only 200-300rpm not 500rpm your hear peoples claimed.

AlwaysinBoost

iTrader: (17)

if your surging you either have a restriction somewhere in your WG or your hotside is too small causing you do make more boost then the engine can actually move. The latter usually only happens at lower RPM so if your getting surge throughout the entire RPM band then something else is up...

600+hp

iTrader: (5)

Actually when I had the .48 hotside I did not have this problem granted I only ran 20-21 lbs. Now I have to keep it at 18-19lbs to prevent surging w/ the .63 A/R

Drifto

iTrader: (6)

A Garrett 3076 should have the ported shrouded cover. Are you sure it's a 3076? I do not understand why Precision is telling you no. Look around on the e-net for a 3076. They all have the cover you want. Here is one particular link http://cheapturbo.stores.yahoo.net/garrettgt3076r.html

600+hp

iTrader: (5)

Maybe the person that I talked to was just too lazy to get his azz off his chair and actually do the checking, maybe he's just clueless, I don't know. Otherwise I would have it swapped before making the 500 miles trip from KC to Chitown to get it tuned on alky at AMS.
Turbo is one of the earlier unit from AMS about 3 yrs old.
I hope the new ported unit will bolt onto my turbo. AMS told me the new 3076r is slightly diff ? may need some mod to make it fit.

Just hope they have something I can use

BlouchTurbo

iTrader: (10)

Are you using the 4 inch inlet cover ? If you have a true GT3076R and need the compressor cover with a ported shroud give us a call. We have it in stock ready to ship.

GTVEVO

iTrader: (22)

Before you buy a ported cover be sure to research the exact turbo you have. There are several GT3076R's , two of the most common are the -12 and -15. The (-15) will not support a surge ported cover built for the -12 even if you change the compressor ring, in other words you can't get a surge ported cover for the -15. You will need to have a TO4S cover drilled to get the antisurge affect. The -12 usually comes with a surge ported cover and a 2 inch outlet from the compressor side. If you current have a TO4S cover and a 2.5" outlet on the compressor side you most likely have the -15. Just find the number and check to be sure before you spend money and have more setbacks.

In all honesty you could try this and it shouldn't cost you too much other than the headache you are putting up with. Good Luck

kiddevo

Where do you find the -12 -15 #s on the turbo.
THANKS

GTVEVO

iTrader: (22)

Usually you can find the number on the inside of the compressor cover usually behind one of the bolts and ring fittings where the cover pulls down on the ring back plate. You can find this by removing them as if you was to change the front compressor cover, you will usually just see SS15 or somthing of that nature. Or usually you can find the Center CHRA Number on the turbo as well stamped on the center section. Most likley if you don't have a surge ported cover it is probably a -15 if it was spec'd to flow 52lbs.

Otherwise you will need to measure the Inducer on the Comp Wheel to be sure. Good luck.

600+hp

iTrader: (5)

GTEVO,
thanks for shedding some light in this matter. I finally feel like we're getting somewhere.

Blouchturbo,
I'll be calling you as soon as I find out exactly what the specs of my turbo are.

BlouchTurbo

iTrader: (10)

Let us know if we can help

600+hp

iTrader: (5)

Just got an email from Precision turbo


It depends what CHRA is in the turbo. There are three different versions
available but the Garrett ported cover only fits (1) of the CHRA's. Look on the
center section of the turbo for a six digit number follwed by a dash then a four
digit number. Or, look the compressor cover discharge for an engraved number.
This will help us positively ID this turbo

Looks like my chance of the ported cover fitting just went from 50% to 33%.

GTVEVO

iTrader: (22)

Exactly right, the covers are not interchangable. the -12 is the only turbo with the ported cover, otherwise you have to machine (Drill) your own TO4S cover.

Also there are 5 different GT30s made by Garrett, if the turbo came from precision I am betting it is -15 which is not good news. Unless BlouchTurbo can vouch for a ported housing custom made to work on a -15 turbo, not a -12 cover with the 2 inch compressor outlet becuase it will not work even if you change the compressor back plate and ring.