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Hay guys I have the 25/40 set up on my 34 now makes a good 250 rwkws but runs out of puff in high rpms

Its is worth changing to the 28/71r to get my 270 rwkws.

I have all the surporting mods.

Just over runing out of boost at high rpms

cheers heaps

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Is it worth the hassle for another 20kw? I'd be looking at something to make 300-320kw and make the change over worth while if you want more power.

What RPM do you get full boost with the 2540 (HKS I assume?)

Correct me if i'm wrong but doesn't the GT2540 have a 76mm compressor, aka a Garrett GT2876?

This turbo was a bit of a miss match as the tiny 53.8mm NS111 turbine wheel couldn't produce enough drive to spin the compressor effectively. The other issue the large compressor caused was choking the tiny turbine, i'm assuming that you would have a 0.86 housing so that would help. The GT2871 is a slightly better matched turbo but you won't seen much gain from switching.

If you really want to swap switch to one of the GT30 series turbos, they are a much better match for a 2.5 litre. I would suggest a GT3071 (even a GTX3071 for mid to low 300's), or as Ryan suggested a TD06-20G if you want to move away from Garrett.

Will be ordering a 3071r in the next few weeks. going to change cams as well.

I took for a spin today and I was wrong makes full boost around 3200rpms and holds until about 4500rpms and just drops off.

I drops of psi due to the small rear housing, good for response but not so good for holding it.

Wanting around 270 to 290 rwkw

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