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Rb26 Twin Turbo Upgrade Specifications - Would Like Specifics With Models, Sizes Etc

The Mafia

By The Mafia,
in Engines & Forced Induction

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The Mafia Grand Master

The Mafia

Posted
Posted

Hey everyone, I Need to clarify a few things.

There are so many f**king kinds of these GTR twins..... I want to understand them better and know what sets them apart. This is going to get confusing but I need some help filling in the blanks.

Stock = GT28??, ?? compressor, ?? trim, ?? inlet diameter, ?? turbine

-7 = GT28??, ?? compressor, ?? trim, ?? inlet diameter, ?? turbine

-9 = GT28??, ?? compressor, ?? trim,?? inlet diameter, ?? turbine

-5 = GT2860, 60mm compressor, ?? trim,?? inlet diameter, ?? turbine

-10 = GT2871, 71mm Compressor, ?? trim,?? inlet diameter, ?? turbine

HKS2530 = GT2860. 60mm compressor, ?? trim, ?? inlet diameter, ?? Turbine

GTX2860

GTX2863?

Ahh this is driving me a bit crazy.

Maybe even point me to a document that details all of this and I can do it myself?

Found these but they state nothing about the -5, -7, etc names:

http://www.forcedinductions.com/Completegarrettlisting.htm

http://www.turbobygarrett.com/turbobygarrett/sites/default/files/catalog/Garrett_Catalog_V5.pdf

breaker1845 Community Regular

breaker1845

Posted
Posted

Might be what you are after basically. File I found on here or one of the gtr forums a while back.

Can't guarantee this information is 100% correct as I didn't create this spreadsheet.

gtr_turbos.xlsx

The Mafia Grand Master

The Mafia

Posted
  • Author
Posted

f**king perfect. You guys are awesome. They look pretty spot on too.

Will give me an idea of what is available, and I am going to try and add GTX turbos to it.

The Mafia Grand Master

The Mafia

Posted
  • Author
Posted

okay so I have the information I need.

Now I need to work out if I can cram the GTX core into some housings that will bolt straight onto my stock manifolds, intake pipes, and dumps.

Does anyone have any suggestions?

tMW6DL2.jpg

As you can see, the GTX2860 is between a -5 and a -9. I'm assuming with a billet wheel it might even spool a little earlier. There was a huge thread I read a while ago where someone had crammed a GTX cartridge into some stock housings (bored them out) and got some good results.

I'm thinking that my HKS housings aren't any good (and won't simply bolt on)

breaker1845 Community Regular

breaker1845

Posted
Posted (edited)

What are your current turbos? You'll get good results and better spool for sure, but the process can be quite expensive of changing cartridges if you don't already have them available.

I've also read that thread, can't remember exactly what was done but it involved a lot of machining and money, haha.

Also what purpose would you be trying to achieve out of doing this rather than just upgrading to something else all together?

Edited by breaker1845
The Mafia Grand Master

The Mafia

Posted
  • Author
Posted (edited)

It's a number of stupid reasons why I want this:

- I want early spool and still a decent amount of top end (GTX are good for this)
- I want everything to simply bolt onto the factory positions (intake and exhaust)

- I want newer billet wheels

- I want my cake and to eat it too

I have emailed GCG to see what it would cost to machine my HKS front and rear housings onto some GTX2860 cores.

If you have a look at the picture up there you can see the GTX is right in the middle of the -5 and -9.

The GCG rep in QLD said that this combo should be on at about 4,000rpm which would be good and drivable.

I like to hit the race track 2-3 times per year too by the way.

Hope all of that made sense... my ADHD is giving me a hiding today lol.

Edited by The Mafia
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infamous_t Veteran

infamous_t

Posted
Posted

There was a huge thread I read a while ago where someone had crammed a GTX cartridge into some stock housings (bored them out) and got some good results.

Here you go :)

I guess you could use the OEM comp hsg so sleeving is not required, In my humble opinion this would be a compromise so I just used some old HKS2530 hsgs which are T04B style (aka 5s) with an AR of 0.6

The OEM hsg. A/R is 0.42 and although from what I have read the A/R on the comp. side does not affect things too much unlike the hot side A/R which has a major affect on spool.

Using the OEM comp hsg might make it boost slighty earlier possibly hotter also. Just what I have read.

Anyway I prefer the HKS 2530/2510 gt2860r-5 housings of 0.6 A/R.

I just turned up 2 x 6061 aluminium alloy sleeves 60.00mm OD 42mm ID x 48mm long. Bored out housing to 59.94mm . heated the housing up with heat gun (measuring it to make sure its bigger than 60.00mm) , cooled the sleeves down in freezer then dropped sleeves in the housings. Once cooled machine the profile to suit . Interference fit is permanent like welding but no distortion. I put 2 scotch keys in as well although that was overkill but thats me. The important thing is the 0.06mm interference!. Best not to press it in cold either as it may gall.

Hope this helps some people out wanting to use GTX2860r CHRAs' with Skyline housings.

Keeping my fingers crossed they will be better than my 5s in every way.

breaker1845 Community Regular

breaker1845

Posted
Posted

Sounds like an interesting adventure and would be good to see a comparison between your current setup and the gtx housings once complete and how much it makes a difference.

Quite a few people seem to be interested in a hybrid -9 to -5 as they want a bit more than what the -9 provides but not as much as the -5.

The Mafia Grand Master

The Mafia

Posted
  • Author
Posted

well, will be both fuels

So about 320-330awkw on BP98

380awkw and beyond on E85 maybe?

Hard to say, but I would like to be all in at 4,000rpm (18psi)

The Mafia Grand Master

The Mafia

Posted
  • Author
Posted

haha not really that worried about what power it makes, I just want the most power with 4,000rpm - 18psi

bloody twins are a pain in the ass

The Mafia Grand Master

The Mafia

Posted
  • Author
Posted (edited)

yep, and no comment.

The solution is easy - either -9s or GTX2860s in housings that bolt onto the factory intake and exhaust.

Edited by The Mafia
Piggaz Grand Master

Piggaz

Posted
Posted

Mafia, are you planning on stroking this at any stage or strictly a stock engined car? If not, a set of -5's and a step 1 v cam which you can use with stock pistons will definitely help you reach your goals.

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