motoxxxman

as the title states, I'm looking for recommendations on who can machine my compressor housing and backplate to accomodate a larger compressor wheel. Current turbo is a Garrett 60 trim t3 0.63 a/r. It has the 2-bolt inlet, and used to have the 2-bolt outlet but I shaved it into a standard outlet with a lip for a coupler. It's the stock turbo for an SVO mustang or turbo-coupe. I've officially maxed it out and want a larger compressor wheel without buying a new turbo or complete cold side assembly.

looking into using a t04b wheel, or an evo 3 16g wheel. yes I know the shaft size is different than the 16g wheel, I have that covered already if I go that route.

TheShodan

iTrader: (14)

Ok. So, I'm trying to get this straight. You want to use your Garrett 60 "trim" compressor cover and put in a larger compressor wheel into it, but you're still not addressing the turbine wheel (the actual creator of top end power) because you've maxxed out what you are currently running, which is a Garrett 60 "trim"..... Are you sure that's what you mean? What you ask is rather backwards. You also need to let us know what power level you're looking for, as you may be maxxed out with any of your options, regardless of trying to save some money on covers.

So, if you don't mind, I'll give everyone a little background, so that others reading this might understand my premise a little better.
The Garrett T04E "60 Trim" uses a 58mm inducer and a 74.93 exducer compressor wheel, which is already larger than any of the Standard cast wheels used in the Garrett or Turbonetics family of T04b wheels. The Turbine wheel is at 65mm inducer, capable of about 500whp at it's peak, so that's pretty good.

The Garrett T3 60 "Trim" on the other hand, uses a 46.5mm inducer/60.1mm exducer, and is still smaller than a "Super 60", in which even though they have the same exducer (60.1mm), the compressor wheel is still smaller at 48.3mm.

First, we have to make sure we're understanding which "60 trim" you're referring to for this, because in either case, these Garrett/Turbonetics choices are still larger than the Evolution 16G you plan to use. (Although in all fairness, the T3 60 "Trim" variant is only about 200ths of a millimeter larger than the 16G, running the same size 48.3mm inducer wheel.. It could technically work, but you'd run into an efficiency issue in the exducer, in addition to the MHI & Garrett inducer profiles being different even though they are both the same size.)

Next, let's presume that you're referring to the Garrett T3 60 "Trim" that uses the 48.3mm/60.1mm combo in this.. (I'll call it the G4660) just so that we're all talking about the same unit here.
In fact, To help with this nomenclature, I'll nickname all of these units:

T3 60 "Trim" = G4660
T3 "Super 60 = G4860
T04E 60 "Trim" = G5875

Ok, so say you have the G4660, and you're saying you've maxxed this out,
1. Why are you attempting to put in something smaller than what you have when you say you want to use the Evo 3 16G?
2. You do understand that the compressor wheel isn't responsible for what makes the higher end power you need to keep from "maxxing" turbochargers out, correct?
The turbine wheel size and profile are responsible for that part. .

3. For the 50 trim sized 16G (Big 16G) and the 60 trim 16G (Evo 3), you'd be using the same turbine wheel and profile (49mm/55.8mm) which is still smaller than your G4660 (54.6/64mm).
This is presuming that you have the G4660. However, even if you don't, and you possessed one of the other 2 nicknamed examples above, you're still smaller than what you have.
You need to address the turbine wheel size and profile first before worrying about the compressor.

So, now the compressor/turbine inefficiencies are out of the way, let's see about the idea of using a T04B Cast wheel from Garrett/Turbonetics, as they were still working together when these was made.
(I'm assuming you're referring to the cast compressor wheels, as you haven't said anything else)
We have the following:
H-Trim
V1/V2 -Trim
S-Trim

Which almost all used a 65mm exhaust wheel diameter (only difference is the turbine exducer which is either 53.8mm or 56mm), and were larger than any of what you're proposing to utilize in order to get the higher top end power you're looking for.Unfortunately, your idea requires, at the very least, a new compressor cover, or the facilities to have it machined out, which is actually more expensive than getting a nice used turbine housing.

In this case, you're going backwards here, and it's not worth the additional cost for what it costs to get another turbocharger entirely, be it new or even slightly used.
In most cases, the cost of a turbocharger is rarely the sum of its parts. Here, you're better off going with a fresh start

I know that wasn't exactly what you're looking for, but there was a logic to my answer to this.. NO.. Get another turbocharger.

Does this at least give your thought process a bit more perspective?

motoxxxman

it does give me a little bit of insight, though I suppose I can explain my situation a bit more now that you've mentioned all of this, and some clarification.

my turbo:
compressor: 46.5mm inducer, 60.1mm exducer (0.60 a/r, not that it matters)
turbine: 58.9mm inducer, 48.7mm exducer, 0.63 a/r

evo3 16g:
compressor: 48.3mm inducer, 68mm exducer
turbine: 56mm inducer, 49.2 exducer

As you can see, my turbine is already larger at the inducer, but only 0.5mm smaller exducer. and the 16g compressor is a good amount larger overall. flow maps for the 16g are also closer to where I want them.
And the main reason I'm looking into changing just the wheel and modding the housing and backplate is because I built this car from the ground up for autocross, needing quickest spool possible and lots of midrange power. and it does exactly that. And I really don't want to lose any spool time on the turbine side because it's perfect exactly how it is now. But this included a custom made turbo manifold I built, and I built it around my current turbo thinking I'd never want a bigger compressor. the turbo sits where the a/c compressor used to be so it can blow almost directly into the fmic. there's less than 7 inches between housing outlet and fmic inlet. Now, a byproduct of building it like this, I only have about 1/2" clearance between the housing and the block/alternator/alt bracket. I simply can not use a larger compressor housing without making a new manifold or heavily modifying this manifold.
I've also been reading up on the SVO forums for a while now because thats what the turbo is, and it turns out a lot of guys are running to4b compressor wheels in their stock housings, turbine side left untouched, with much success being able to pull an additional 20-30hp out without changing boost level, and typically being able to run about 3-4psi higher before hitting the same wall of running out of breath.

thoughts?

motoxxxman

to add: I have not confirmed 100% that my current limit is due to the compressor. I have merely come to that conclusion through research and some math. I may soon weld a nipple to the collector on my manifold to connect a pressure gauge to so I can see how good/bad the backpressure is.

currrent power level is about 380whp 405tq, with my 2psi boost drop. I'm looking to get to 420hp and 410tq with consistent boost.

motoxxxman

and if I do end up having to upgrade the turbine, that's easy. simple housing and wheel swap. which is why I'm not concerned with that side at the moment because that's a no-brainer. the hard part is the compressor side, which I want to get done first before changing the turbine side. out of curiosity, and research purposes, and getting the hard part done first. because there's really no point in upgrading the turbine if I can't upgrade the compressor.

motoxxxman

I've tossed around the idea of trying a true super 60 compressor wheel (48.26mm inducer, 60.1mm exducer), as it would be much easier to install only having to mildly mod the compressor housing and no change to the backplate. It may or may not get me to my goal, but I am willing to experiment because it definitely wouldn't hurt anything and would still allow a larger wheel to be added after too. The only problem with that is I can't for the life of me find a true super 60 wheel for sale anywhere. everything I've found listed as a super 60 is actually just a regular 60 trim wheel, or the 60-1 wheel which is not even close to the same.

Which brings me to the evo 3 16g. because if that also doesn't work, there's still more room to go bigger. The t5/6 t04b (54 trim) is the wheel I have my eyes on if it gets to that point, or anything with similar ind/exd sizing

TheShodan

iTrader: (14)

I see where you're coming from. But from experience, the Evo 16G just doesn't get to where you think you would without a lot of boost pressure to compensate. MHI CHRAs are one of the most premier, robust, cartridges on the planet. However, since about 2010, prices for parts alone for genuine MHI parts have increased by over 300%, and that's for the dealer/distributor mark-up!! This is why you see a flood of eBay and similar Evo 16Gs that are out there, but the problem is their CHRAs can't handle the thrust loads that the efficiency maps tell you that they can provide; Not only does it not fill it well on paper, but in actual utility, they have become disappointments, hence why other companies who used to be MHI distributors found it within their best interest to either create their own, for their particular markets, go through another company like IHI, or just not bother with them at all.

As for the T3 60 "trim", you're not going to find them. They discontinued those years ago. Garrett has a habit of cleaning out their closet of applications that no longer are worth creating/packaging/selling, about every 2-3 years . It used to be every 4 years, but with the advancement of disruptive technologies that can create wheel applications enmasse, their marketing push with their own GTX and GTX Gen II line, and other competition getting away from cast wheels, it only makes sense they they discontinue selling/using them. The best you'll find are the T3 "Super 60 = (G4860), and T04E 60 "Trim" = (G5875). At least when it comes to newer pieces. The T04E 54 "Trim" cast compressor wheel has been discontinued for over 10 years.

The contour of the backplate still has to be taken into account. The Garrett wheels have a curvature that comes to a flat point on their compressor wheels (cast & billet), while the MHI and IHI sizes are completely flat on the backside. The makes so that you have to create a type of "concave" in the backplate, and that's where that's going to be tough to be machined. Again, not saying it can't be done, but in the end, time/cost may be more than what you're willing to put into it. Wantboost was always frustrated about that part when he wanted to reprofile his housings and backplates for other wheels.

I wish you the best of luck. I like what you're trying to do, but with today's "disposable" thought processes, you're going to have a helluva time finding these components. And I'm speaking to you as a long time "collector" of these rare finds.

TheShodan

iTrader: (14)

So much easier to do this..

https://honda-tech.com/forums/classi...325hp-3299548/

motoxxxman

Just a minor correction because I think you're a little confused, or maybe it was a typo. I have a 60 trim currently. the super 60 is what is impossible to find.
My 60 trim wheel has a curve on the backside, and the genuine evo 3 16g compressor wheel has the same curve and backspacing. so for the backplate, the only thing I'd have to machine is the radius, which is flat in my setup from the factory, it is not curved to match the wheel. So it'd just be extending the radius out 4mm. easy for me to do. the compressor housing is the hard part due to the profile difference.
If I go with a evo 3 16g wheel, I'd be keeping my complete turbo and just using the 16g wheel, so the mitsu chra isn't of concern to me. As stated originally, yes I know the difference in shaft size, I have that covered already as well.
the t04e wheels are too big for what I want, that's why I'm considering a t04b, and I have found several in cast and billet. I've also found several genuine mitsu evo3 16g wheels for cheaper than you might think

So. Does anyone have any recommendations on who can modify my compressor housing for a new wheel?

motoxxxman

lol that's actually a good find. thank you, I'll keep it as a consideration for spare parts or as a whole. the problem though again is that compressor housing may not fit with my setup.

TheShodan

iTrader: (14)

It's a T04B cover. If that's not fitting, you've got some serious refitment to do with the exhaust manifold, downpipe, radiator placement. It doesn't get easier than a t04B.

motoxxxman

I have not been able to find any dimensional drawings for standard t04b covers. Any insight?

TheShodan

iTrader: (14)

No insights, really. Just get one from eBay for $50 or so, and start measuring.

No innovation without investment....