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Atr43ss-2 Prototype Initial Tune 250rwkws 18psi<2500rpm, Stupidly Responsive


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Looks like the turbo could be out of flow. Given there is a 20rwkw drop from 5000-5700rpm :)

I'm guessing the results drop severly hard after 5700rpm? That is why run stopped?

Were there any issues with boost control or just compressor running out of puff/flow?

for what it's worth the stock turbo looks like;

160km/h = 5714rpm = 195rwkw

170km/h = 6074rpm = 189rwkw

the stock turbo seems to peak at 5700rpm ish

and the prototype seems to peak at 5000rpm ish

this is based on my stock turbo tune

neither is right or wrong just offering data

i think a 33 GTST with that powerband would be pretty sweet on the street

its a good 50rwkw ahead everywhere in the power band so it should be shit hot

for what it's worth the stock turbo looks like;

160km/h = 5714rpm = 195rwkw

170km/h = 6074rpm = 189rwkw

the stock turbo seems to peak at 5700rpm ish

and the prototype seems to peak at 5000rpm ish

this is based on my stock turbo tune

neither is right or wrong just offering data

i think a 33 GTST with that powerband would be pretty sweet on the street

its a good 50rwkw ahead everywhere in the power band so it should be shit hot

Looks like a tad bigger would be far better suited to the motor though. Enough to get it flattening off around the 6500 mark would be far better.

Impressive results nonetheless.

i drove this car today.. it is an ANIMAL of a street car! absolutely in love with the response... congrats Stao :wub:

i didn't really rev it out to redline, probably only about 5.5k, so i didn't get to experience the drop off in power.. still heaps of fun though

I'm modeling a turbine housing that has external gate ports in and out to have an external gate replacing the current actuator setup. So boost control issues is going to be history. shortly.

Looks like the turbo could be out of flow. Given there is a 20rwkw drop from 5000-5700rpm :wub:

I'm guessing the results drop severly hard after 5700rpm? That is why run stopped?

Were there any issues with boost control or just compressor running out of puff/flow?

looks to be like the compressor has plenty of puff and the exhaust housing is out of flow..

No NO. Please do not cancel your trip for this turbo. There are still few things I'm doing to get it perfect. I will make it commercially available when ready.

With the drop it could be if the housing's maxed, external gate should solve abit of that issue. We see what happens.

I too can attest for this turbo, Stao let me take it for a spin on saturday. Car is super responsive, 1st and 2nd gear are just insane and third pulls very nicely but looses the insanity slightly. But by then your doing over any legal speed limit anyway. So if its response your after I would definitely recommend this.

Thanks again for the drive!

Would I be right in saying this is a HKS GTRS replacement?

Would I be right in saying this is a HKS GTRS replacement?

I dont believe so... needs to touch 280-290rwkw and maintain its topend while still beeing internal gate to get up on same level, i'd more so go with its a 2530 replacement considering the figures and much better response...

I would say it looks a close thing with a HKS GT-RS although it is coming on quite a bit earlier.

Getting a HKS GT-RS to 280-290rwkw is stretch with very few getting there from what I have seen.

250-260rwkw is probably a more realistic expectation.

^ yeah but holding to 7500-8000rpm is also looking like a problem.

Although given a lot of people want bolt-on replacement for "stealth", not sure going to external gate is going help sales as such :P

^ yeah but holding to 7500-8000rpm is also looking like a problem.

Although given a lot of people want bolt-on replacement for "stealth", not sure going to external gate is going help sales as such :P

agreed, the exhaust housing to me really seems to be the bottleneck in the setup.

My GT-RS is managing 253rwkw at only 14psi (i know different dynos vary, but thats on the godzilla motorsports one).

So im hoping its capable of 270rwkw-280rwkw with 20psi through it.

This turbo looks alright.

I dont believe so... needs to touch 280-290rwkw and maintain its topend while still beeing internal gate to get up on same level, i'd more so go with its a 2530 replacement considering the figures and much better response...

I have never seen one make 280-290 rwkw on a stock rb25.

Same as I dont think I have seen a 2530 make 250rwkw...

seems like this thing would drive like a V8 haha.

i think its near impossible to have a turbo be as responsive as this and make decent top end.

the small rear housing will refuse to hold high boost at high rpm, therefore peak power at 5,000 odd.

but peaking at 5,000 i think seems a waste of the revving nature of the RB.

truly a street turbo; lots a power in the early rev range, but with no top end.

would be interesting to see how you go with boost control.

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