What's the diff between the stage 4 & 4GT. Is it the turbos? I thought the stage 4 already used the K16/24 hybrid turbos. These hybrids aren't anything new for EVO/IA. So how does the stage 4GT get +100TQ in the lower rev ranges over the "standard" stage 4?

 

I believe the GT uses Garret turbochargers, just as the stage 5 does.

 

Are these the GT series turbos as shown on the Garret website? Are they ball berring? How do they compare to the K16/24 hybrids? How do they compair to zero tollerance coated hybrids? How do they compare to zero tollerance coated Garrets? Where's a guy tojump in. It's kinda like when I bought my 386 SX-16 computer, which in it's day was quite hot. It took me forever to buy a new personal machine. Things were changing soo fast. Now the same seems to apply o modding the 996TT. Does Moore's Law apply to modding?

 

isn't there a programming difference too? also fuel pressure reg, pump, intake, etc..????

phd - elaborate

 

Checkout www.evoms.com and all the answers are there....
In brief:
Level 4 includes: 600HP GIAC program, exhaust, headers, K24 turbos (or modified K24s - not hybrids though!!), air filter, dump valves
Level 4GT: proprietary custom Garrett turbos in K24 housing (hence direct bolt-on), headers to match, 4GT 640HP program (pump gas), optinal IBE switch with race program! Also need an exhaust, air filter and dump valves.
I also would definitely get an upgraded clutch with witehr as my stock clutch was slipping like crazy running the IA600 my only time at the drag strip!! (my inexperience did not help either)

 

Mr. Sindi... very good. I should have known the answers to several of these questions as I frequent evoms.com. But, I am still confused. There's been a lot of chatter from Kevin and I would assume Stephen through association, that these Hybrids are very hot. I need to know the order in which the turbos rank. (mostlly street and some track. Lag not a good thing). Would this be a correct ranking (bad to good)?

1. K16
2. K24
3. K16 - coated
4. K16/24 hybrids
5. K24 coated
6. K16/24 - coated
7. Garrett Customs (STG4-GT)
8. Garrett Customs - coated

Is this close?

Kevin - are you coating any and all turbos or are there limitations. Are you coating both hot and cold sides in all applications? What is the risk of the coating pealing off the coldside (if you do the cold side) and blowing into the cylinders and wrecking ****?

Stephen - do you have programming for all of the above? I know it depends on the other mods, but assuming the standards: exhaust, D. Valves, filter are already done. Is it necesary to do the headers? There seams to be some question about it's necessity ( in the low to moderately modded range). At what HP are headers a must?

Anyone - at what point are GT2 or custom high efficient intercoolers necessary. Who does a freer flowing intake that doesn't shatter (scargo)?

Mike

Sorry for so many questions, but I must know the answers or I'll go crazy!

 

It is not that straight forward...
Stock TTcomes with K16 with which exhaust and tuning can get to I guess 520HP
X50 GT2 come with K24s which with exhaust and tuning can reach 600HP
The zero clearance coating thing is Kevin's baby and he is the sauthority on that...From my understanding, zero clearance coating helps improve turbocharger efficiency and reduce lag . I do not believe it will help increase CFM (air flow). Note however, that sharky's turbos (and DUanes) are K24/K16 hybrids with large impellars and a bigger cold side I guess to increase CFM...Increasing air flow (the whole point of bigger turbos) with proper tuning WILL gain you HP.
There was a thread a while back about K24 vs. K16/K24 hybrid and I asked Kevin about zero clearance coating K24s instead of hybrids but he said that hybrids perform much better and respond faster. His custom hybrid flows more than my stock K24!!
Of course I am no expert on this and Kevin (although near impossible to reach) is the authority on turbochargers!!

 

Well I guess the delima (for me ) lies here...

I was pumped on the Stage 4-GT. Sounded great. Custom Garrett turbos in K24 housings etc, etc, etc. Lovely! NOW we have this K16/24 Zero Clearance coated super turbo! If packaged with the same supporting components as the STG4-GT, how does it compair?

 

Zippy - I am exactly in the same boat as you...I am lookingto upgrade to either or package. The shootout makes it even harder as both are pretty darn fast!!
They are also similar in pricing unfortunatley....What about we get one each and if we dont like it swap LOL (j/k of course)
Note that for zero clearance your car needs to be shipped to IA (special process to install and break in zero clearance so as not to fdamge turbos, coating or engine) whereas 4GT you can buy the parts from Stephen at IA or Todd at EVO and do it locally...

 

Kansas is a long drive Dorthy!

 

LOL

 

Uhhh... what about real Garrett ball bearing turbos, like my T04's?

Surely they flow a hell of a lot more than the K24's.

 

Hamann, what can you tell me about your T04's. (I love details, so don't be shy!)

 

Hammann and I are both running the Garrett T04 dual ball bearing turbos that flow the most out of any of the turbos you listed. They also make mega power, as my car proved being the most powerful out of the 9 cars at the shootout.

Also proof is Hammanns 10.7 quarter mile time and my 132 mph trap speed.

T04's rock!

 

Zippy,

You have to look at more than just turbochargers when upgrading your car. You can add any turbocharger that you want, however the turbocharger upgrade will do nothing without proper software to accommodate the increased airflow/airflow characteristics from a different turbo. The EVO Stage 4GT upgrade system uses a Garrett based turbocharger, which has been modified to fit into the KKK housings and we offer software to match the output of the turbos. We had these turbochargers built this way so that they would bolt right up without any modifications.

The Garrett turbocharger that we are using has a more advanced turbine design, which helps it spool up faster than the KKK 24 turbocharger. In addition to the better flowing turbine wheel, it also has a compressor wheel that will flow more air than the KKK-24, thus increasing the peak power output. This turbocharger is small as compared to the turbocharger that Buddy and Tyson are running. We built this turbocharger to offer the best of bottom end power (ZERO LAG) while making plenty of power on the top end. It offers the best of both worlds for any street / race application.

The software that Garrett of GIAC and I developed for this car was carefully designed to maximize the power without sacrificing reliability or drivability. We tuned the street (Stage 4 GT) software on 91-octane fuel. The power output is 640 HP and 670 TQ. The boost is set at 1.4 bar in the midrange and it tapers off to 1.2 bar by redline for safety. Our race gas program (Stage 4 GTR) generates 740 HP and 705 TQ. This program runs 1.4 bar in the midrange and drops to 1.3 bar by redline on 100+ octane fuel.

I hope this clarifies the differences in turbochargers