No actually there are some unique design features on the GT-K which Garrett does not offer on the GT3582 at least out of box. Things like surge porting and ceramic coating on the turbine housing. You could absolutely get the GT3582R turbine housing ceramic coated at your own expense but be prepared to pay some fairly large dollars to have a ported compressor housing for that unit. Oh and that doesn't mention the fact the compressor and turbine on the GT-Ks are brand new designs so they very well may be something special. My point is the GT3582R isn't some brand new ultra perfect turbo. Its been out for a while and while the design does lead to improved turbine flow its not something that you can't find elsewhere. And BTW the turbine tips on the GT3582R aren't exactly the longest or most extended turbine tips out there.

 

Surge porting actually makes the compressor less effiecient. There is no free lunch with porting. The GT-K will come at a huge premium concerning it's price.

We should be comparing the spool up characteristics of what turbo I have now, and the GT3582R. I think the spool up will be acceptable on the GT despite the 1.06 A/R. Not saying that it can't be found elsewhere. But the GT3582R will fit with minimal modification. It fit's the bill, is relatively innexpensive, and is available now. All 3 important factors.

JET

 

Where exactly are you getting this info. Porting the shroud can improve spool up times and prevent surging on larger compressors. If it was only a negative impact no one would do it including Garrett who does offer it on other units. If you feel the GT3582R is what you want go for it. Its your car do what you want. I'm just trying to help you. If my help is not welcome then it won't be offerred. And since you brought it up the GT-Ks are no more expensive than the HKS units which you guessed it also come with sure porting. Again HKS is not in the business of making compressor worse. $2480 is the cost of the T04R . Of course that MSRP just like the price listed so far on the GT-K. I've never seen anyone pay MSRP on any part or even their Z.

 

I'm just trying to have a discussion.

JET

 

Well you are telling me to only compare the turbo you have now and the GT3582R. I'm sorry but I don't feel that is the turbo you need. If you are going to buy a turbo regardless of the brand or make I would want to know I got the turbo that best matched my needs. I don't feel the GT3582R is it for your car. But if thats the only turbo you want to discuss although I'm trying to help you explore more options than theres no point in my posting any further on the subject. I have already told you the limitations of that unit that I can see. If you still feel its the best for you go for it. I think there are better options. I have posted both Garrett and Turbonetics options on this thread so clearly I'm not being biased one way or the other.

 

BTW the HKS T04R and T04Z should also work...spool up should be good and they both have T4 turbines with varying turbine housing A/Rs. Should also spool up quickly and have more than sufficient flow for the power you want.

 

I didn't say that there were no benefits to compressor porting. Of course there are, but don't look past the negative aspects of it like it is a free lunch.

The GT40 will more than likely not fit due to the size of the compressor and turbine housing. Clearance to the intake pipe is minimal. Any closer and heat soak will be an issue if it would even fit. There would be no way to get my turbine housing jacket between the turbine and the intake pipe.

The limitation that you point out are beyond the limits of my goals. I only want 475whp. You stated in your opinion that the 3582 would flow up to 500 whp.

JET

 

I thought a good portion of the quicker spool on the GTK turbos was due to the redesigned inconel (lighter) turbine wheel?

 

Yes thats one of the items as well. The GT-K uses all Iconel 10 blade turbines that are a new design. The compressor section is 351 Al that is heat treated as well for longevity and is a new design also. These comined with all the other items will improve spool up. Keeping the heat in the turbine section helps as well so the ceramic coating will help some too along with keeping the engine bay cooler.

 

The affect on compressor efficiency is minimal when compared to the benefits of surge porting. It may not be a "free lunch" as you call it but its only costing $0.01 when compared to the performance gains. I think you will see a lot more companies following this path very soon. HKS already does using Garrett units they that machine and modify as well as Garrett themselves. Borg Warner does as well. I'm fairly certain Holset is also doing this. Clearly Turbonetics is and has been for a while. Thats 4 of the top 6 turbo makers. Although I believe Precision and Innovative or both doing it I won't say they are cause I've never seen their units with it.

 

I saw precision units last year at PRI with porting.

 

And there we are... Surge porting is rapidly becoming standard on high performance turbochargers. As more people research and develop their compressors they come up with new and better ways to create porting that is extremely effective with little to know adverse affects. The porting used on the GT-K and HKS units is quite a bit different from the ports Turbonetics, Garrett, Holset, and Borg Warner use for the older diesel truck units (big turbos)

 

Heres some info on the GT-K (highlighted areas we've been discussing):
This next generation of turbo units features special Map Enhancement Porting to allow the compressor wheel to operate at its maximum efficiency across a very broad rpm range. This variant of bleed air design, has precisely placed lots machined into the compressor housing to limit effects of surge when using large turbochargers on small displacement engines as well as providing additional air flow to make maximum horsepower at high boost pressure levels and across the entire rpm range. Aerodynamics is what separates the GT-K turbo line from the competition. Equipped with the latest HP Compressor wheels, designed to maximize efficiency at high boost pressures, and the F1 Turbine wheel, created to capture maximum exhaust gas energy and reduce back pressures, the GT-K family of turbos delivers unequalled performance. Turbonetics HP Compressor Wheels are made of 354 heat treated aerospace aluminum and are manufactured utilizing Hot Isostatic Processing (HIP) to allow these wheels to be incredibly strong. When paired with the Map Enhancement Porting of the GT-K compressor housings, these wheels flow huge volumes of air at high pressure ratios while still delivering a cool efficient intake charge. The F1 Turbines are a new generation of 10 bladed, tall tip height wheels that allow you to turn up the boost without encountering dreadful backpressure issues. Made from 713C Inconel and balanced to Turbonetics exacting standards, these wheels match up with the HP Compressor Wheels to make the best turbocharger combination available. Turbonetics exclusive Black-Chrome Perma-Coating also comes standard for heat reflection away from the compressor housing to aid in lowering compressor wheel inlet temperatures and gives these units great looks to match their performance. Select turbo systems will also be able to be upgraded to the GT-K Turbos if so desired. Turbine housings will feature high temperature ceramic coating to trap exhaust gas energy inside the turbine housing for greater energy delivery and faster response time, as well as keeping the engine compartment temperatures low. Cooler under hood temps means more power potential from a cooler compressor intake charge.

 

And an excerpt regarding Borg Warners porting:

BorgWarner did not stop there, the compressor cover is fully cast to match the compressor wheel, not adapted from some other application that wasn't designed for performance. The cover features a fully functional port shroud known as Map Width Enhancement Grooves that allow air to be pulled and fed directly into the second set of blades on the compressor wheel outside of the main inlet. This most noticably increases the efficiency of the compressor as well as over air flow, hence the name, Map Width Enhancement Grooves: it produces "wider" compressor maps!

 

Holset has been doing it since like 1997....

 

when will your 3"downpipe finished?i have a gt35r with 0.78 ar..im going use this instead of the 60-1..

 

Pretty much everyone has been doing it for quite some time now...