Discosteak

iTrader: (1)

I recently bought a car with a Precision gt4067. It took me alot of searching to find info on this turbo as Im guessing not alot of people used it. I did fianlly find info on the sizes of the wheels
Compressor Wheel: inducer 66.9mm exducer 84.5mm height of blade 36mm
Mine has the H cover
Turbine housing .81 T4 with 3inch V-band
Turbine Wheel Inducer 78.33mm exducer 70.04mm height of blade 38mm

My question is can this turbo be upgraded to a billet compressor wheel, and is it really worth it to do so? I would really like to keep the car 67mm, as i would like to be able to run in the true street class at MIR. I would like to try and squeeze as much power out of the turbo as i can without upgrading it to a newer unit. Unless it would be more cost effective to upgrade to a different 67mm unit.

Before anyone says it i do not want to upgrade to a BWs400sx. the car still gets street driven and has an open t4 exhaust manifold I do not want to switch manifolds or move to a turbo that laggy.

if anything i would switch a 6766/68 or an s300 91/79

mar778c

iTrader: (1)

Yes, check PureTurbo and Boostlab. Those are the 1st companies that come to mind.

Discosteak

iTrader: (1)

checked them both sent an email to pure turbo. Now onto the other questions. is it worth it? Anyone think its possible to get this turbo to perform as well as a 6766? it does have a larger turbine wheel. Im kind of curious how this turbo would do with a precision 67mm billet wheel instead of the cast wheel.

TheShodan

iTrader: (14)

It's not worth it, if the quality of aluminum is not good (the cheaper ones are a lower grades that use 2618, while higher quality ones use aircraft grade like T6 7075 aluminum.. Used in aircraft materials for better durability and strength). The whole "lighter weight rotating assembly" marketing, really has no merit at 160,000rpms.

In addition, you want to see if there were any aerodynamic changes to the compressor wheel to present certain characteristics. For the big power that this turbo gave when Precision was still associated with Garrett, a high conversion, lower rotational speed configuration was best used, especially for the larger engines it was used on.

But to have "billet" just to say to have it, and its not made of a better material with a change in aerodynamics, you might be making things worse than what you have currently. So it's not an easy choice. Those companies that have offerings like the ones suggested, you should contact them and ask those questions. If their not able to give a reasonably direct answer, flag that in your memory.

TheShodan

iTrader: (14)

Mmm. There's not a real answer to that. Considering that the configuration of the 67mm Precision is about the same as you already have, I'd question the real motivation for making that kind of switch to that compressor wheel. See what it does first, then if change is needed, research a bit more. But that doesn't mean it's needed at this time when you haven't worked with what you have first.

Discosteak

iTrader: (1)

the car made mid 600's at 30 psi on c16. I plan on switching to id2000's and e85, which should give some power increase. In theory if the car has a precision 67mm cast wheel and i were to switch to a 67mm precision billet wheel would it not have some sort of gain? I asked both companies if it would be possible to use a precision wheel for the upgrade. Id be willing to pay to do it if i could at least match the performance of a 6766, or at least come close.

TheShodan

iTrader: (14)

Again, you're going off the notion that because "its billet" automatically means that its going to get better all around. Your top end power is going to be based upon your turbine wheel, not the compressor wheel in this case. You're using an older GT-S exhaust wheel on that combination, which is LARGER than the one used in the 6766 combination currently. (You have a 78.33mm wheel diameter compared to the 73.8mm-74.2 diameter of the 6766, I can't remember specifically off of the top of my head.).

In addition, the contour of lead splitter blade between the Precision 67mm "CEA" profile and the one you currently have is very similar, and at that rate of speed your current wheel is experiencing at that boost level, there are some serious concerns that you'd face with that. At over 3.07 Pressure ratios, that current wheel is at about 110,000rpms. At that diameter of over 66.5mm, that's a lot of potential flex if the material isn't correct. I also PM'd you some other info regarding "wheel flex".

Discosteak

iTrader: (1)

Thank you

h22apwrd95

iTrader: (1)

I have the same turbo, except with the S cover. Mine came off the old IPG car. Same hot side as well. I would ask Innes/IPG their opinion on the turbo. It is a solid Garrett piece. Just sent mine to Shodan for a preseason checkup. Made 52x @ 20psi on an 81.5x89mm on E70. See what it will do on an 83x89mm running Ignite E85 this season.

TheShodan

iTrader: (14)

I'll post some pictures of yours in a moment. I'll be checking out what's going on when I get an opportunity.. Looks a little rugged, but at first flush, it seems salvageable. LOTS of oil on the turbine housing and some on the heat shield. I'll see what's going on soon. I'm thinking the compressor wheel should be replaced , but a little larger, like a 70mm, since you have such a nice turbine wheel at 78.33mm

h22apwrd95

iTrader: (1)

Definitely interested to hear your thoughts on the wheel sizing.

Discosteak

iTrader: (1)

same here

h22apwrd95

iTrader: (1)

I should be hearing some news early next week.

SPOOLINmatt

did you call precision?

TheShodan

iTrader: (14)

Why? What are they going to do? They don't deal with Garrett any longer

Discosteak

iTrader: (1)

Any word on this yet?

TheShodan

iTrader: (14)

Yes. I'll be PM'ing h22apwrd95 sometime today, then give a synopsis if he approves of that.

wantboost

iTrader: (2)

Billet isn't always better

*cough*precision*cough*
6262*cough*

Lol

TheShodan

iTrader: (14)

I sent him the information about the turbocharger. The GTS turbine wheel of that GT4067 is more than any 6262 or even Reaper can give. The only problem is that its an abomination of a turbocharger and as a whole very difficult to duplicate, and even worse to fit with other compressor wheels whether they be cast or made of good billet aluminum, because the shaft is so large (Uses the same turbine wheel as the GT4092R), so that causes some issues on a journal bearing package such as this. I see very easily why this was discontinued in 2007. You're basically taking apart 2 turbos to get one.

Bottom line is it CAN be repaired for a reasonable cost, but upgrading the compressor wheel would not be worth it, and would have no guarantees of longevity due to what has to be done the wheel just to get it to fit. No matter what company he would try and give it to, opening up the through bore of the wheel could compromise the system if its attempted. The closest and best thing would be a 70mm, but its rather costly to do.. Its one of those, "It can be done, but shouldn't be done.

rico892002

Mac have you guys came out with your new turbo yet?

wantboost

iTrader: (2)

Mac you always know I'll stir the pot when someone mentions billet and precison in the same thread :D

I've seen the new turbo but have been sworn to secrecy. I could tell you but I'd have to kill your whole blood line

Discosteak

iTrader: (1)

maybe ill just wait for that new 67mm turbo from theshodan

wantboost

iTrader: (2)

I would

His customer service is miles above most companies the average customer will encounter. I've worked selling parts for a long time (mostly special order on the phone with top tier people) as well as doing up to 5axis cnc mill work for a lot of companies.... so I've seen typical stuff

And Macs' customer service rivals that of the best top tier yamaha/suzuki rep or any tucker rocky/parts unlimited rep.


Not to mention machine work and build quality is great, as the units are only made on a build to order basis so no mass production there. I've had a turbo from mac for almost 10 years.

I'll never go through another turbo guy again, unless it's for small items or a "billet" wheel to measure and compare

Mac is also a great teacher, when me and him talk he's more than accommodating and will help you to his best (and even beyond with some issues)

To the point where Im tinkering with my own custom "hybrids"

Mac will never steer you wrong or try and price pop you. He works within your budget,, desired power levels, the purpose of your car, and your turbo budget