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fresh build only making 210hp at 19Psi of boost. Very lazy doesn’t build boost till 5000rpm.

So my car just got broken in on the dyno. Fresh build with Manley 86.5mm pistons 9:0:1, Manley h beam rods, BC 264/264 cams. ARP hardware, ACL bearings, HKS GTIII-SS turbos. 3 bar map / Haltech 2500 ECU. After breaking in they threw it on the dyno and tuned it.  checked everything. No boost leaks, no exhaust leaks, no shop rags stuck in intercooler piping. It made 210 at 14psi then they increased boost to 19psi and increased injector duty cycle and still the same 210hp. leak down test 10-15%, compression 120 120 140 140 140 140, waste gates are properly adjusted and car hits target boost level. Not sure what it could be. Do not have dyno sheet from shop. They’re going to take it out on the street and data log tomorrow. Anyone have an idea of what could be wrong?

Edited by Brodys_92GTR
21 minutes ago, Duncan said:

I'd start with the timing; both the belt itself and potentially any adjustable cam gears.

Or, maybe that is why no-one uses journal bearing turbos any more :)

He already asked this question earlier on a Facebook group, I have the same turbos and in 4th gear it should be at 10 psi around 3200 RPM. Uneven compression across the the cylinders is not a good sign, especially by that much. I would also question the cam timing, it's possible the cam centerlines were not cut correctly or some other issue with the aftermarket cams, supposedly Brian Crower has QC/QA issues.

  • 3 months later...
On 10/23/2023 at 2:31 PM, Duncan said:

I'd start with the timing; both the belt itself and potentially any adjustable cam gears.

Or, maybe that is why no-one uses journal bearing turbos any more :)

Um, yeah. No. I have GTIII-SS turboes. Just dynoed on Sunday. 446rwhp/387ft-lbs @ 18psi/1.24bar. Very fun to drive. Busted my hump putting her together. Impressed by the turboes. The JB and single turbo nonsense Australians are infamous for needs to die on the vine.

51 minutes ago, anicenero86 said:

Um, yeah. No. I have GTIII-SS turboes. Just dynoed on Sunday. 446rwhp/387ft-lbs @ 18psi/1.24bar. Very fun to drive. Busted my hump putting her together. Impressed by the turboes. The JB and single turbo nonsense Australians are infamous for needs to die on the vine.

We have only been playing with gtrs for 30 years and build the best in the world, what would we know?

  • Like 3
1 minute ago, UWISSH! said:

We have only been playing with gtrs for 30 years and build the best in the world, what would we know?

Congrats on being experts on ONE chassis. Now bow down to GM and Ford for even branching out to your continent. Anyway, I'm not going to go tit for tat with you. Got some ex-military buddies out there in AU and don't want to give off the impression that I dislike Australians. Twin scroll single conversions are not the end all be all because some dude from Motive who makes videos said so. 

14 minutes ago, anicenero86 said:

Congrats on being experts on ONE chassis. Now bow down to GM and Ford for even branching out to your continent. Anyway, I'm not going to go tit for tat with you. Got some ex-military buddies out there in AU and don't want to give off the impression that I dislike Australians. Twin scroll single conversions are not the end all be all because some dude from Motive who makes videos said so. 

U will probably find that the majority of people on here think he is f*#kwit

  • Like 4
12 minutes ago, UWISSH! said:

U will probably find that the majority of people on here think he is f*#kwit

Good. glad to know we feel the same way about each other. I created an account to share some info, not battle the Australian single-turbo hivemind/echo chamber. Have fun! 

2 hours ago, anicenero86 said:

Um, yeah. No. I have GTIII-SS turboes. Just dynoed on Sunday. 446rwhp/387ft-lbs @ 18psi/1.24bar. Very fun to drive. Busted my hump putting her together. Impressed by the turboes. The JB and single turbo nonsense Australians are infamous for needs to die on the vine.

Glad you are happy with your choice, do you have a dyno graph to share (and, what dyno was it on?)

My direct experience is 20+ years racing on journal bearing turbos due to class rules, and watching those with modern BB singles on the same motor driving away in a straight line, is your experience one dyno pull?

I'd expect that coming to the forums and telling everyone their experience is "nonsense" will get you a bit of push back.

  • Like 2
6 minutes ago, Duncan said:

Glad you are happy with your choice, do you have a dyno graph to share (and, what dyno was it on?)

My direct experience is 20+ years racing on journal bearing turbos due to class rules, and watching those with modern BB singles on the same motor driving away in a straight line, is your experience one dyno pull?

I'd expect that coming to the forums and telling everyone their experience is "nonsense" will get you a bit of push back.

Sure. I just posted them in the GTIII-SS topic. We ran seven pulls on dyno packs. I'm not arguing BB vs JB here. That is subjective, regardless. I'm arguing that they aren't "junk". Same goes for "twins in the bin" talk. Basically, go and tell all of Japan and the US that their cars are trash because your nation's tuners have decided on such. It's nonsense because this "my way or it's trash" that gets peddled on here is tiresome. Of course I expect pushback when it's 5-7 years of an echo chamber. It's like the MAF vs MAP conversation. From an installation perspective having did all the work myself and never bringing my GTR to a mechanic in five years, single is the preferred option. I won't argue that. But driveability and "fun", I prefer the twins. And no, the Motive video with a borderline PRP salesman saying "this is better" won't convince me. 

I think there's some silliness going on with THE_BEST option being lauded as the only option, and second, third, fourth best options which may be 5% worse being regarded as utter junk.

Logically though, if you have a stock GTR, and you want to update it's forced induction system, you have an option of purchasing one turbo and a manifold, or two turbos and a manifold, or two turbos on the stock manifold(s).

If you're gonna buy two, one would hope that you'd get any benefit at all out of spending double the money, but uh, that's not what happens.

I hated that Andrew Hawkins video purely because he uses a single/double combination from completely different generations of turbo and makes conclusive decisions based on that. He's gotten a lot better since then in his objectivity to be honest.

Would love to see what would have happened if it was a GTX3582 and Twinscroll that he used vs two Borg Warner EFR's and a fullrace manifold making the same target power at same target boost, you know, like some adherence to the scientific method when doing things.

But would probably still find the same, spending much more money for potentially no benefit at all is why people would be against it.

The turbo is the only thing on these cars that produces power, so everyone gets a bee in their bonnet when people spend tons on a motor build then buy a cheap garbage turbo.

THAT SAID;

There's not enough variation in turbo tech in the world to explain why someone makes 450hp (American horsepower or otherwise) on 19psi with twins, and someone else makes 210hp on 19psi with twins. There's very obviously something missing going wrong/unexplained/dyno is configured wrong and car actually makes 380hp or something :p

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