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I'm after anyone running a HKS GT-RS on an RB25DET, (genuine HKS kit, not a Garret equivalent) to post up their dyno graphs.

Specifically their boost graphs.

I'm running one on my car and have been for some time, but only recently 'finished' the package off with injectors and a Z32 AFM...

It made 253rwkw on 18psi, but boost isn't holding in the top end, which is why I'm after other's GT-RS graphs, as well as any similar experience with boost not holding, and how you overcame it if you did...

My car has all the supporting mods, with most mods being Jap brands and not cheap chinese copies.

Thanks in advance :)

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do you have an electronic boost controller? Honestly every dyno graph I've seen I always seem to see the boost pressure starting to drop off at the top end mine included. My tuner said that it's very common for skylines. I'm sure someone will disagree and probably has more useful advice.

How much is the boost dropping off and how quickly ? Post up your dyno graph if you have it handy

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I am interested in this as mine is also dropping off albeit on GTSS on a 26, but the same question ponders, I am going to replace the EVC6 to see if it is defective failing which I will wind up the HKS actuators to set them at 14 psi (currently at 11) so the evc only has to hold 4 psi above the actuator pressure rather than 7.

I hit and about 18ish for say 1,000 rpm and then as with the above, it tapers off a couple of psi down to low 16's.

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I have the same problem as well, it peaks at like 19psi then falls to like 17psi, no matter how much I stuff around with the duty cycle settings.

I thought my BOV was leaky, so I put a rubber sheet between the stock BOV & the cross over pipe, no difference. I thought it was the actuator, but after seeing dyno graphs, it seems to be the norm.

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