So i have my newly built forged engine but im still stuck on turbo choice.
I would really like 400whp on my 2.1L ej207 (272 cams)

I was originally limited by the decision to stay top mount process west intercooler
I have decided to go a good quality front mount. Will a blouch 20g xtr get me to 400whp or will i have to go bigger.

If i need to go bigger what are the options (im not familiar with the gt3xxxx series of turbos.

Also definitly staying 98, no e85

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STi Ver 6 | 2.1L Stroker | 418whp | 11.5 @ 199kph |

Not fast enough dammit!

Twist mount or front mount gt3xxx of your choice will get you to that power but e85 is highly highly recommended it will be a struggle to get 400 on 98

using the Perth-WRX mobile app

A gtx3076r would get you to 400hp just i would think. You can get them in subaru stock location configuration. Or twist mount. A twist mounted one will perform better than a stock location one. And generally will be cheaper to buy the turbo. But you gotta factor in cost of modified uppipe/downpipe intake. And external gate too. A 20gxtr mighy do it maybe. But it will be ringing its neck.

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Doing it for all the wagons out there

Im using a twist mount gt3076 with 0.82 rear tune will be in a month ill let you know how it goes. I did previously have a twinscroll td05-20g 10cm rear it would have gone 400 on my now stroker but e85 only not a chance on 98 ...

Including pedalstool/ adaptor, turbo and wastegate was under 2k i did fab my own dump screamer and what not tho

using the Perth-WRX mobile app

I had a JDM 207 with a Litchfield LM450 Billet on it which is basically a GT30 core with a stock position exhaust housing.

With 98 and 15% Methanol mix it made 504HP at the flywheel / 422HP at the wheels.

On a properly built and tuned engine you should piss 400whp with a GT30 sized Turbo. Especially if you run E85.

For reference Here's my graph. First is flywheel, second is at wheels.

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605whp
Quarter Mile in 10.9 seconds @ 135mph /217kph
0-100 kph 3.2 seconds

Thanks for the advice guys

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STi Ver 6 | 2.1L Stroker | 418whp | 11.5 @ 199kph |

Not fast enough dammit!

So im looking at going the atp3076 gtx stock location turbo to give me room to move later if i choose to go e85.

Now whats the difference between an external or internal gated turbo?

Also anyone have any idea what rpm this size turbo will spool at on a 2.1L

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STi Ver 6 | 2.1L Stroker | 418whp | 11.5 @ 199kph |

Not fast enough dammit!

Internal gate has a flap over a small port in the rear housing.. external is a separate valve "external" of the turbo generally an external system will have a better seal against leaks and better boost control

using the Perth-WRX mobile app

Also. You may find boost creep issues with something that size (gtx3076) and internal gate. Its because the wastegate cant flow quite enough volume though its tiny opening and that means some of the exhaust that should be bypassed, will instead be directed through the turbine. Increasing boost beyond target boost.

I have a blouch dom 2.5 xtr (gt3071) and it has what i believe to be a boost creep issue with the internal gate. The wastegate opens at about 19-20 psi - bench tested with a mity vac pressure tester and also eveident by the gate pressure when run on my previous td05 and also on the dom2.5. (I use the same actuator on both turbos.) But when the turbo and exhaust is hot and flowing well and driven through multiple gears) wastegate pressure creeps up to as much as 25 psi. I run no boost control solenoid. The turbo is plumbed direct to the wastegate actuator. The BCS is simlly plugged in to keep the ECU happy. So there is a boost creep of about 5psi or 25% from what it is during a single pull vs multi gear pull with pre heated hot exhaust etc.

Im putting it down to a boost creep because of the small internal gate trying to flow a big volume of exhaust.

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Doing it for all the wagons out there

Gtx3076 will piss in 400 atw.....even do it on 98.
External gates are Sooooooo much better, its not just their size its the method of control.
Stock position subaru flange turbo's suck......don't expect some mungral "3076 core" in bolt on subaru housing to perform anywhere near the same as a t4/t3 genuine Gtx3076

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MY99 WRX EJ2.35L 720whp 9.48@147mph
https://youtu.be/c_lYEG0_Dyo