Sounds like a nice bump to me. I think my concern with going "big" turbo was losing low-end toque. I am running E30 so no need for aux fuel. I don't want to run E85 w/ NX2 because I feel that would be a bit too much torque for the stock motor and daily driving.. cost is also a factor and the kits are like $1400. My goal is essentially maximizing the motor (keeping in mind daily driving) without going into the red zone. With the NX2/E30 I'm guessing 400+whp and 440ish wtq which is plenty.FBO or FBO + Nx2: 400 to 440 wtq
All depends on your fueling. 91, 93, E85 available for E30? Methanol 4 port injection?
With an air filter, intake elbow to replace accordion thing, colder plugs, colder tstat, alky straight 100% meth injection, and a custom tune on 93 octane a forum member hit 385 whp / 440 wtq. Stock turbo, bypass valve, intercooler and exhaust. This is my pick for the best bang for buck setup.
The stock clutch won't handle multiple launches at that power level but with soft launches it should be ok. Also 400 to 440 wheel torque is the most that's safe for the stock bottom end.
The NX2 takes over in the higher rpm range where the stock looses efficiency and is capable of flowing enough air to bring power and torque levels into the 500+ zone but only with more supporting mods such as a built bottom end, cams, ported head and aux fuel.
I like that turbo response curve a lot for a predominantly street driven RS. Its expensive though. Was trying to work out if I could buy an EFR 6758 and do a turbo swap myself, most of the fittings are straightforward. But I cant figure out what the turbine housing to exhaust manifold adaptor plate is or where to source one. Looks like mountune use a custom adaptor. Mountune is always out of stock as well.There's always the BorgWarner efr-6758 that's in the Mountune m450 kit in the UK. That setup doesn't lose as much of the low end as the NX2 or other bigger turbos. You still need forged internals.
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m450 MRX Power Upgrade Kit [Mk3 Focus RS]
The mountune m450 MRX upgrade replaces the OE turbocharger with a Borg Warner series larger frame unit to deliver incredible power output with minimal increase in turbocharger lag, greatly enhancing the driving experience. Tested and validated over thousands of miles and countless hours on the...www.mountunestore.com
But the trick would be to find a tuner familiar with the setup in the US.
I believe you can order the BW turbo from APG Turbo and pick and choose your fittings accordingly. Not sure if the available options will match the RS through. The one benefit (for me) was that the NX2 is drop-in. I got a smoking deal on it (lightly used) with the upgraded WGA so I'm stuck with what I've got haha, but still happy nonetheless.I like that turbo response curve a lot for a predominantly street driven RS. Its expensive though. Was trying to work out if I could buy an EFR 6758 and do a turbo swap myself, most of the fittings are straightforward. But I cant figure out what the turbine housing to exhaust manifold adaptor plate is or where to source one. Looks like mountune use a custom adaptor. Mountune is always out of stock as well.
No doubr you have a great turbo.I believe you can order the BW turbo from APG Turbo and pick and choose your fittings accordingly. Not sure if the available options will match the RS through. The one benefit (for me) was that the NX2 is drop-in. I got a smoking deal on it (lightly used) with the upgraded WGA so I'm stuck with what I've got haha, but still happy nonetheless.
Are you still running the original bottom end or have you upgraded?Had my NX2 and tuneplus actuator fitted today, on a base tune from tuneplus at present
I have forged pistons and rods in std 2.3 block with no closed deckAre you still running the original bottom end or have you upgraded?
I would like to get someone's opinion that has dropped in the NX2 on a fully bolted stock block with Tune+ base tune that is capped at 420 WHP.
just posting to say to others I too had to switch from nx2 wastegate to turbosmart wastegate to a dual port turnosmart wastegate. Anyone who goes nx2, instal dual port from the startI used Adams Tune+ custom actuator and it failed to hold boost higher up solution was to use a Twinport.
Now holds a solid 2bar all the way to 7200rpm I could have had upto 36psi but it’s fast enough at 537whp
just posting to say to others I too had to switch from nx2 wastegate to turbosmart wastegate to a dual port turnosmart wastegate. Anyone who goes nx2, instal dual port from the start![]()
Good thing I've got that then! Almost switched to Mountune's recirc valve but didn't lol. I'm still on the stock setting though. Did you have to adjust it post-NX2?Totally agree with MEXRS
The TurboSmart Twinport is a must for the NX2 NOT an option but a must have item
The NX2 is just a CHEAP turbo and it's drop in. I could definitely get a great quality turbo that's smaller to better pair with my power limit but it'd cost me double what I got for my NX2 ($1000). I have debated forged internals to achieve more HP but I'll also need a fuel rail to run E85, that's like $2500 in parts alone and the install service quote I got was stupid expensive.I too have a standard 2.3 block but forged internals inside the motor. I also added a deck brace.
Why an NX2 if your going to strangle it at 420hp It’s good for 600+. A smaller turbo would give you that or even the OEM unit and no lag