GTW line is available with ball bearing. Basically, it's an upgraded compressor wheel mixed with the older turbine wheel tech to keep costs down. It should be around the price point of Precision but actually be reliable. The GTW compressor wheel flows a ton. The GTW3476R and GTW3884R are screaming deals for power/$ and are great for the boosted street car market. I'd guesstimate the 3476 is a 550whp turbo and the 3884 is 800-850whp turbo. For track cars, I'd still stick with the GTX line as they have better overall efficiency. But of course, they cost a lot more.

Anyway, back to the EFR. In terms of efficiency, BW is not hiding anything as they have published their compressor maps. Compare any of the BW compressor maps with the Garrett GTX compressor maps, size for size, and you will see the GTX have higher peak efficiency. The EFR compressor wheel does typically have better surge margin. X622 is correct, mm for mm, the EFR will not make the peak power. Of course, no one is showing their turbine maps.

Which brings us to the TiAl turbine wheel. Fact: TiAl is much lighter than standard inconel turbine wheel material (about 50%). This gives it a measurable response in time-to-torque, like around 35% improvement. This is what everyone talks about with regards to what you feel when driving the car but don't see on the dyno. Much the same as ball bearing. In my opinion, the compromise in using TiAl is reduced turbine efficiency due to the thicker blades required. Why are the thicker blades required when using TiAl? My guess is due to poor flow for cast ability. Of course, EFR uses ball bearing for better transient response too.

Okay, so we've established EFR will not make equal power to other competitors but does have class leading transient response. EFR also has stainless steel turbine housings which is the best material for handling high exhaust temperatures such as on modern gasoline and track cars. The only better material would be inconel.

I wouldn't consider Precision, Comp, Xona, etc in the same field as Garrett, BW, IHI, MHI, Holset as all these companies are OEM suppliers. They must design their wheels to be reliable to OEM standards, so no super thin hubs or blades. As far as turbocharger weight, Garrett for sure designs all their housings to contain a wheel burst which does add weight.

Anyway, everyone should just understand what EFR offers: good power, best transient response, highest grade turbine housing material.

 

The P-trim is a laggy turd. Yes, it makes power but it's garbage on response. Seriously the GT42R turbine spools better and makes WAY more power.

I think the GTW3684 uses the "T350" (aka T3 stage 5) turbine wheel. Which is a cut down GT37 wheel. I could be wrong but it's dimensions seemed to line up when I took a glimpse it.

As for saying the GT35 turbine is dated, the PTE CEA stuff is a knock off of it...

You guys focus on the size of the wheels, but go ahead and overlay "turbine maps" between the EFR and the GT stuff and you can see EXACTLY the differences between how these two companies approach the issue of response vs power. The GT series DESTROY the EFR on flow for a given major diameter. Garrett simply tried to minimize wheel size to reduce inertia where BW went with lighter materials.

Before you say BW is more technologically advanced, I'm pretty damn sure Garrett went down the road of TiAl turbines LONG AGO and found them to be unreliable. There was a post on this very board from somebody at Garrett eluding to exactly that anyway.

 

double post FTMFW

 

URQaudiguys results are all in this thread, around page 200.


Sure Garrett's turbine wheels flow more per mm. That's because they've been a longtime subscriber to big compressor small turbine methodology. Only recently have they come to grips with the fact that compressor/turbine diameter match matter.

I agree that the P-trim is kind of a turd, that's disappointing about the GTW line.

Precision's turbines are better than the Garrett's they originated from IMO.

 

is there any point in discussing power per mm.. ?

for street and amateur road race use it is about power vs. width of powerband (or as some would say SPOOL) vs. transient response

pro race throws in antilag into the picture and then the spool characteristics look a bit differently..

 

Re: GTW line, cost vs. performance. GTW3476R ~$1400 (comes with turbine housing in cost). GTX35765R ~2300 (with turbine housing, $1900 without)

Precision turbines might flow more, but they won't hold up to Garrett's fatigue life/stress criteria. There's a reason why you only see Garrett/BW/IHI in motorsports applications.

 

Some of the custom Garretts Joe uses all use P-trim turbine wheels and make the power I previously mentioned but they are combined with a 62mm compressor, not a 67. What I'd be interested to see is a custom 62mm wheel with a GT40 style turbine wheel which is something I'm also planning on testing eventually. The reason I'm not a fan of the GT35 turbine wheel is probably because of how well the GTX35 62mm compressor wheel seems to flow combined with a larger turbine wheel in custom applications.

 

Anyone need a B2 Turbosmart WGA I bought the wrong one for my EFR.

$100 buucks brand new

 

what is wrong with it for the application?

 

The 35R wheel is great when combined with a smaller compressor. Its a bit surgey with the 82mm wheel. I have a 59mm inducer'ed billet wheel and made 621awhp on an Audi A4 1.8t on 32psi/E85 .63ar housing. Not shabby and spools pretty quickly for a turbo this size. I have run the EFR turbos and the mid sized ones do not leave me totally impressed. I would take a 30R over a 7163 any day as it just plain feels stronger.

 

I don't disagree, but we may have different ideas of what is an acceptable level of match up. I always error on the side of better turbine match ups but I've also seen some "mis-matched" combos that absolutely ripped. I've also seen the extreme of it though too where the mis-match was so great that a little 40lb/min turbo was one of the laggiest turbos I've ever driven. Roll into it in 4th on the freeway and it had full boost at 2800 RPM...drop into second at 5500RPM though and you wouldn't get full boost until mid way through third gear...

Why do you say that? (not a loaded question)

From appearance, the blade profile and thickness are very similar between them, but I'm also not a PTE man simply because of their historical reliability issues so I fully admit, I probably don't give them a fair shake. Are you are going off strictly a performance basis from experience?


I will fully acknowledge Garrett is lacking in the turbine department. Also, I'm not too sure the GT40 turbine wheel can go into anything for custom turbos? I think the GT37 turbine maintained the old school T3 shaft size so that's how we ended up with the T350 turbine wheel. I think the GT40 is a different sized shaft though that is basically specific to the GT40 CHRA?

You could cut the shaft down, that's what the old "GTQ" turbine was. It was a GT42 turbine that the shaft was machined down to work in standard T4 CHRAs. They were crazy unreliable though as you might expect.

 

Finally fitted up my 7163 with the Full-Race manifold last night.

Notes:
- Fitment is good but tight
- No cutting or trimming!
- Crossing my fingers that my fabricator can fit a mandrel off the hotside for the downpipe


Untitled by Alex Whitacre, on Flickr

Untitled by Alex Whitacre, on Flickr

 

Looks really nice awhit17, I'm a little jealous. I'm waiting on my 8374 kit from Driven Fabrications to finish up. It's supposed to have minimal trimming.

 

Thanks, I know trimming is almost unavoidable with the larger B2 frame stuff, but I was pretty happy none was needed with the 7163 since the big IWG hotside and the actuator can make things complicated. Getting everything on still took time though lol.

I'm really excited to see how this turbo works on my car, in theory it should be perfect for what I want, the 8374 is a beast too!

 

You might want to take some hi-temp black paint to the SwainTech coating. I know I got annoyed any time it got dirty on my old stuff lol. Black paint solved that