New Garrett Gtx2860R / 2863R / 2867R

[Ecozile]

I have followed this thread before making my mind up on a pair of turbos to go on a RB28. I have back to back results on same car/dyno with -5 (with HKS 2530 turbine housing) and GTX2863 (Machined -5 front housing with HKS2530 turbine housing).

Unfortunately there is a problem with boost drop at high rpm (which I believe has nothing to do with turbos) which does hide true potential but GTX turbos makes more power on lower boost than the -5 as one would expect.

I would like to see GTX2867 results either on a 26 or 28. Has anyone done that?

[mr skidz]

I have followed this thread before making my mind up on a pair of turbos to go on a RB28. I have back to back results on same car/dyno with -5 (with HKS 2530 turbine housing) and GTX2863 (Machined -5 front housing with HKS2530 turbine housing).

Unfortunately there is a problem with boost drop at high rpm (which I believe has nothing to do with turbos) which does hide true potential but GTX turbos makes more power on lower boost than the -5 as one would expect.

I would like to see GTX2867 results either on a 26 or 28. Has anyone done that?

Dyno sheet post up would help more, you might be experiencing a couple of things how big is your exhaust system what's the smallest id.

headwork/cams fitted?

Your compressor wheel might be pushing more air than the turbine can handle "choking" which is my only fear with using this turbo as revs climb and power increases turbine wheel will struggle to discharge it all.

[Daz]

Feck I'd love to see some results from a pair of gtx2867s too

[Piggaz]

Feck I'd love to see some results from a pair of gtx2867s too

Friday!

[Daz]

Friday!

Lol you got it in your diary don't you

[mr skidz]

Anyone seen GTX2860's with oem .42 compressor covers with .64 exhaust housings?

I have a feeling they would hit the 600 horsepower mark at the wheels and be the most responsive thing out there that's my guesstimate especially on a 2.8!

[Ecozile]

Friday!

So what's happening on Friday?? Tell me you are mounting a pair of 2867 in to a RB28

Skids, I will get the dyno sheets up soon.

I wasn't clear on my last post, the boost drop on high RPM was an issue before fitting GTXs on.

Smallest ID would be 70mm on the front pipes but there are two 70mm pipes merging in to 80mm. Rest of the exhaust system is bigger than 80mm and no cat. Fully ported head. Cams are 270 duration, 10.80 lift.

I doubt it is the turbine side choking as the GT-RS uses similar size turbine with a larger compressor wheel than GTX286X variants.

[Piggaz]

So what's happening on Friday?? Tell me you are mounting a pair of 2867 in to a RB28

Skids, I will get the dyno sheets up soon.

I wasn't clear on my last post, the boost drop on high RPM was an issue before fitting GTXs on.

Smallest ID would be 70mm on the front pipes but there are two 70mm pipes merging in to 80mm. Rest of the exhaust system is bigger than 80mm and no cat. Fully ported head. Cams are 270 duration, 10.80 lift.

I doubt it is the turbine side choking as the GT-RS uses similar size turbine with a larger compressor wheel than GTX286X variants.

2867's in a 3.0. Not mine, Daz's.

Merging into an 80 mm? Get rid of that! Bigger

Because the RS's uses the same hot side, doesn't make it correct. The rear is too small on them!

[mr skidz]

So what's happening on Friday?? Tell me you are mounting a pair of 2867 in to a RB28

Skids, I will get the dyno sheets up soon.

I wasn't clear on my last post, the boost drop on high RPM was an issue before fitting GTXs on.

Smallest ID would be 70mm on the front pipes but there are two 70mm pipes merging in to 80mm. Rest of the exhaust system is bigger than 80mm and no cat. Fully ported head. Cams are 270 duration, 10.80 lift.

I doubt it is the turbine side choking as the GT-RS uses similar size turbine with a larger compressor wheel than GTX286X variants.

^what he said,

80mm is not big enough would definitely choke top end with -5's or bigger.

read my last couple posts explaining wheel sizes.

[XGTRX]

^what he said,

80mm is not big enough would definitely choke top end with -5's or bigger.

read my last couple posts explaining wheel sizes.

And will affect response

[Ecozile]

Thanks. I do understand what you say about the exhaust. I have replaced front pipe and the full exhaust - no difference. I know of two cars cracking over 500kw with similar spec exhaust systems - steady boost curve all the way. I suspect it is the stock bov ruining it for me.

Anyhow, on to better stuff. Here are the dyno graphs.

2014 = -5

2015 = GTX

_____________________________________________________________________

Edited June 26, 2015 by Ecozile

[Piggaz]

Thanks. I do understand what you say about the exhaust. I have replaced front pipe and the full exhaust - no difference. I know of two cars cracking over 500kw with similar spec exhaust systems - steady boost curve all the way. I suspect it is the stock bov ruining it for me.

Anyhow, on to better stuff. Here are the dyno graphs.

2014 = -5

2015 = GTX

_____________________________________________________________________

Nothing wrong with the stock BOV.

Here is a direct back to back on my own car

Green line is GT -RS's, split dumps, HKS front pipes and a kakimoto full mega N1 cat back.

Pink line is -5's, Tomei bell mouth dumps and a twin 3 inch exhaust.

Smaller turbos, lower boost, more power everywhere.

[The Mafia]

Those -5 lines are identical to mine. 20psi by around 4700-4800 rpm. (I have the HKS -5s)

Are you running E85?

I have Tomei Bell mouth dumps and a single 3.5inch exhaust.

Edited June 26, 2015 by The Mafia

[Piggaz]

That was on E85, 270 at 10.25 cams, 2.8 and boost controller turned off (modified actuators by Racepace).

[fatz]

people still use twins?

[Piggaz]

people still use twins?

Not for long!

[R32 TT]

people still use twins?

.....if they're consenting adults - sure!

[fatz]

yea only in vic where the police are like the gestapo

nsw happy times for now

[mr skidz]

Nothing wrong with the stock BOV.

Here is a direct back to back on my own car

Green line is GT -RS's, split dumps, HKS front pipes and a kakimoto full mega N1 cat back.

Pink line is -5's, Tomei bell mouth dumps and a twin 3 inch exhaust.

Smaller turbos, lower boost, more power everywhere.

hey Piggaz, what changed in your setup to get you from 420 to your 467 was it just the cams added lift or mostly boost?

[Piggaz]

hey Piggaz, what changed in your setup to get you from 420 to your 467 was it just the cams added lift or mostly boost?

Cams 260 at 10.85

Head

Went from 86.5 to 87 mm Pistons. My oil pump decided to shatter. And a bit more boost.

For comparison when tuning in the new setup, it went 441 at the same boost level with more mid range. Then the boost controller got turned on.

Extra boost didn't net much in the way of peak numbers (30 kW or so), the midrange however was totally different. 75 kW through the middle iirc from controller off to the full effort.