Gt 35X Vs Gt35R

[Bren444]

G'day

It is becoming more of a regular occurrence hearing about the millions of different turbo set ups with different mod's on different cars, and so it does get confusing for the average Jo (such as myself) to understand the difference between certain turbo models.

I am interested to find out some 'FACTUAL' info on the Garret "GT35X" and "GT35R" models.

I have been on the Garret official website and can't seem to find much info on these two models i.e. size differences or which one flows better, which has higher hp rating etc???

In general, I do understand that there are a lot of obvious factors that affect the performance such as rear housing size, engine and capacity in question, engine mods, bearing type etc - but does anyone know as a rule of thumb which turbo is better and why?

Please only comment if you have legit knowledge or factual info.

I know forums aren't normally the best way to find out facts but I haven't had any luck with searching the websites and thought I'd put it out there before I start making phone calls.

Cheers,

Brendan

[scotty nm35]

The billet compressor GTX range has the potential to make more power than the cast compressor GT series turbo's, they do this because they are more efficient at higher pressure ratios, meaning they can run more boost.

If you plan to stay under 20 psi go with the GT, over 20 go with the GTX imo.

[34GeeTeeTee]

Also consider the FP HTA 3582 that seems to get a good write up too over the GTX (no RB results to go from that I know of)...

What engine? Specs? Power goals etc?

[GTScotT]

I know forums aren't normally the best way to find out facts but I haven't had any luck with searching the websites and thought I'd put it out there before I start making phone calls.

You have it completely the wrong way round. Make phone calls and people will sell you whats on their shelf, or what benefits them. Read a forum and you will get HARD FACTUAL EXPERIENCE from people who have tried the turbo and can tell you what to expect.

As Scotty said you can expect the GTX will make more power than the GT when pushing higher boost figures. For example if you plan to run up to 30psi you would want the GTX, under 25 (closer to 20) you would want the GT. Bare in mind that the fuel you run will probably decide how much boost is going to be used. 98ron 20psi, E85 25-30psi. HOWEVER, its been noted that the GT boogy a little nicer with less boost. It has also been noted that the GTX range pick up a bit more lag for the same model number from GT>GTX.

The difference between the turbos is ONLY the compressor wheel and the compressor housing. Both are the same dual ball bearing core and have the same rear housing options. You would want a .82 to have it boogy on an RB25.

Please refer to this thread for further detail:

http://www.skylinesaustralia.com/forums/topic/344089-garrett-medium-frame-gtx-turbos/page-67?hl=%2Bgarrett+%2Bgtx#entry6595146

[discopotato03]

I'm not so sure many people are interested in back to backing these two turbos because they generally know how much power they are aiming for and get a turbo to suit .

Knowns : The GTX version has a bit more of everything including cost and lag all else being equal .

If you are looking for more than the GT version can provide then consider the GTX version .

It looks to me like the GTX3576R was intended to be the replacement for the GT3582R and the GTX35R is aiming a bit higher again .

I think you need to ask yourself what you want power ceiling wise and then buy a turbo that gives the best spread of power whilst achieving you target number .

In the mean time I'd be looking at comparisons of GTX3576Rs and GTX3582Rs provided of course the GTX tax premium is of no consequence . The former will be a bit lighter and more compact because it uses a different compressor housing . Also I'm guessing the GTX3576R may be a little more responsive than a GT3582R because of its smaller diameter compressor wheel .

Your call , A .

[jet_r31]

Id be interested to see a back to back 3540 vs GTx3540 on kill on a RB. I always thought the backpressure and turbine

flow would be the first thing to bring the bigger compressor unstuck, same deal with the 66-67 mm/3540, which must

be fairly close to a GTX3540 comp wheel flow wise but maybe a tad heavier inertia wise im guessing

cheers

darren

Edited May 2, 2013 by jet_r31

[nick81xd]

Im currently in the process of finding out the exact information you need. i have built two identical engines the internal differences being one head is ported more......

Ported head, modified chinese manifold, custom plenum GT3582r with drilled front cover.........18psi-----441hp and on 23psi -----471hp.

Massaged head, 6 boost, greedy intake GTX3582 with port shroud.......18psi....427hp...awaiting new coilpacks for more boost

off boost they arevery similar, the GTX being a little bit laggier coming onto the power then the GT.

Strangly enough the GT3582 with a ported front cover is noiser across the whole rev range. Can pretty much barely hear the GTX but once more boost is run that might change.

[Lithium]

The GTX are definitely quieter, that was part of the intention behind the design - its probably why you have things out there like the FP and PT turbos which (arguably) flow more mm per mm of wheel area... due to just trying to make spool and flow

[sky30]

I have done a swap from garrett gt3582 to FP hta3586 with no other mods or changes.

Two main things ive noticed are the fp turbo spools slightly faster/earlier and the fp turbo holds boost better when running 20+ psi.

The gt3582 would not hold more than 21psi on my engine

[34GeeTeeTee]

I have done a swap from garrett gt3582 to FP hta3586 with no other mods or changes.

Two main things ive noticed are the fp turbo spools slightly faster/earlier and the fp turbo holds boost better when running 20+ psi.

The gt3582 would not hold more than 21psi on my engine

Sounds like a Win/Win situation there

[GTScotT]

 

I have done a swap from garrett gt3582 to FP hta3586 with no other mods or changes.

Two main things ive noticed are the fp turbo spools slightly faster/earlier and the fp turbo holds boost better when running 20+ psi.

The gt3582 would not hold more than 21psi on my engine

 

And the power? Tell em the price son.

[sky30]

I had it on the dyno it made 16rwkw more on 2psi (23psi)more boost, then fuel pump shit itself.

Ive road tuned it to 26 psi at the moment and its going much better. The gt3582 wiuld never let me run the boost i run now, it just wouldnt hold it.

Price was cheaper than gtx garrett if you go to the right places.

[34GeeTeeTee]

So the FP is a decent step up from the GT equivelent... Awesome!

[AngryRB]

getting some ideas hey mat... you know you want that 400kw lol..

[34GeeTeeTee]

getting some ideas hey mat... you know you want that 400kw lol..

What i want and what ill get is 2 different things But yeah it is impressive to see other options on the market that have yet to be tried and tested! Thumbs up to Sky30 for having a go!

[black bnr32]

gtx vs gt 3.2L bmw

[shnaped_second]

I had it on the dyno it made 16rwkw more on 2psi (23psi)more boost, then fuel pump shit itself.

Ive road tuned it to 26 psi at the moment and its going much better. The gt3582 wiuld never let me run the boost i run now, it just wouldnt hold it.

Price was cheaper than gtx garrett if you go to the right places.

Keen to swap over from a gt35 to a fp3586, who are a good dealer for them? prices I found were towards 3k

[Bren444]

Thanks for the info guys - that's definitely summed up a few things for me.

The build was complete a few months back and I am running the GT35X. I was just curious to know which is better out of the GT35X vs GT35R as I've seen a few fellas over here in WA running the R and making cool power figures.

I have just gone to town on my 34 GT-T - brief overview engine mods are as follows;

Built RB25/30 with mild port and polish and standard crank

GT35X with 1.0 rear housing

6boost

Greddy intake

272 cams

2000cc inj

twin 044's with surge tank and walbro primer

500rwhp @ 16psi, 98oct

E85 to come later down the track and obviously a lot more boost potential yet.

The car has been built with mainly track days and time attacks in mind so that's the reason for not worrying about quick response with a smaller turbo rear housing and cams.

I figured big cams, injectors and 1.0 rear housing would give plenty of potential for future power figures even though we are focused on usable power for the track at the moment.

With this set up, I am currently on full boost just before 4500rpm. It is pleasing to feel it come on very strong from 3000rpm though so I think considering the set up, even though it's no RB26 with twins, I am very happy with response.

Thanks to all for your input.

Brendan

[Lithium]

Wow, on E85 that'll probably be quite an eye opener - your setup is definitely more suited to the GTX than the GT, with a bunch of boost it may surprise a few.

Being no RB26 with twins is a good thing in the case of your engine/turbo setup, much better - though I am surprised by the lag.... it should be able to build boost better than that on a 3 litre, I would have thought.

[shnaped_second]

Thanks for the info guys - that's definitely summed up a few things for me.

The build was complete a few months back and I am running the GT35X. I was just curious to know which is better out of the GT35X vs GT35R as I've seen a few fellas over here in WA running the R and making cool power figures.

I have just gone to town on my 34 GT-T - brief overview engine mods are as follows;

Built RB25/30 with mild port and polish and standard crank

GT35X with 1.0 rear housing

6boost

Greddy intake

272 cams

2000cc inj

twin 044's with surge tank and walbro primer

500rwhp @ 16psi, 98oct

E85 to come later down the track and obviously a lot more boost potential yet.

The car has been built with mainly track days and time attacks in mind so that's the reason for not worrying about quick response with a smaller turbo rear housing and cams.

I figured big cams, injectors and 1.0 rear housing would give plenty of potential for future power figures even though we are focused on usable power for the track at the moment.

With this set up, I am currently on full boost just before 4500rpm. It is pleasing to feel it come on very strong from 3000rpm though so I think considering the set up, even though it's no RB26 with twins, I am very happy with response.

Thanks to all for your input.

Brendan

Nice result mate, I thought the gtx were supposed to make power at higher pressure but 500hp on 16psi sounds pretty healthy, comparable to results from xr6 4ltr. Would like to see what happens with e85 and more boost!