There’s nothing quite like unlocking the true potential of a single-turbo RB NEO engine—and this RB25DETT is a perfect example. Tuned by Steve @ Motorworx and running a Haltech Elite ECU, this beast can now put down a solid 400+ horsepower on high boost and 370 on low bost, and it’s as responsive as it is raw with its unique Tomei Turbo OEM bolt on in its low mount position.

The Setup

The RB25DETT is often overshadowed by its bigger brother, the RB26, but with the right setup, it’s a seriously capable platform. This engine came in clean and ready, but we knew there was more to be had with the right brain behind it—enter Haltech.

We opted for full Haltech engine management to take control of fueling, ignition, and boost. The ECU offered the flexibility and reliability needed to extract maximum performance while ensuring safety across all operating conditions.

The Tuning Process

The car rolled into the dyno at Motorworx, where we began by setting a solid base map. From there, we fine-tuned fuel delivery, adjusted timing for peak efficiency, and refined boost control to balance power and drivability.

Throughout the session, we closely monitored multiple channels live whilst tuning namely:

• Fuel pressure

• Boost pressure

• AFR (Air-Fuel Ratio)

• Oil pressure & temperature

Thanks to the Haltech ECU’s data-logging and real-time adjustment capabilities, we were able to find that sweet spot—where performance meets reliability.

The Result? A Clean 400HP +

There’s something satisfying about hitting a round number like 400hp, but this wasn’t about chasing a number—it was about smooth delivery, strong midrange torque, and a healthy safety buffer which heaps more room for scope.

The power delivery is linear and confident, with the Tomei Single turbos spooling quickly and holding boost strong all the way through the rev range. Whether it’s for spirited driving or weekend pulls, this R34 NEO RB25DETT is ready.

Final Thoughts

Over the nearly 3 decades it’s always a pleasure tuning RBs, but this one stood out for how well it responded to changes. Even with the original Nissan ECU with its FCTuningNistune ECU Solution, which got things initially going. Now with Haltech providing the brains, and Motorworx providing the tools and environment to get the job done, the result is a well-balanced 400hp street car with tons of personality.

Got a project in mind or want to wake up your own RB? Get in touch.

The post TUNING THE NISSAN RB25DETT (R34GTT) first appeared on FC TUNING.

The post TUNING THE NISSAN RB25DET (R34GTT) first appeared on FC TUNING.

Its always nice when you have had the pleasure to have been modifying an owners car from OEM, as it were my own, and being allowed to just go with what I would do and spec it out.

This once factory GTT with its still STOCK engine is just an example. Once tuned with an FCTuningNistune ECU it was time to try something different the moment Haltech released their Platinum Pro Plug in range many years ago.

This wonderful owners Nissan Skyline R34 GTT was the first in the UK to have received such a unit. Not wanting to disturb the OEM wiring it made sense to avoid the Platinum Sport Series, which is what I would typically recommend all the time if things are in check and there are no heavy weight modifications or engine swaps.

Fitted with a now upgraded custom made manifold to suit the design and style of the bigger an advanced Borg Warner EFR Series Turbo (7670), internally gated and upgraded fuel system, I decided to leave the block stock as I know with good tuning they are more than capable and I know the car since its days of being imported into the UK. Plus this isn’t the kind of car to be spanked too hard on the track. Just spirited driving on A and B roads with the odd high speed Autobahn.

Naturally, there were other supporting mods in the form of exhaust and injectors etc.

What one ends up with is a vehicle that is still a pleasure to drive, makes more power, is even more economical (as reported by the owner himself) but yet has a kick to make anyone grin once the turbo comes up. Enjoy my friend and look after her.

The post TUNING THE NISSAN RB25DETT (R34) first appeared on FC TUNING.

Still on the stock turbo for now as it’s a daily runner but maybe a little more power in the future.

The post TUNING THE NISSAN RB25DET (R34) first appeared on FC TUNING.

Future mods to include an even bigger turbo capable of 600 + hp which will really turn this nice winged GTST into a fast road weapon.

More to come so watch this space.

If you like your Nissan Skylines remember to hit that LIKE button below and Share to a friend.

The post TUNING THE NISSAN RB25DET (R33) first appeared on FC TUNING.

Engine still in OEM form, just the usual RB bolt ons, but the owner will be looking forge the engine for long term reliability.

The stock RB25DET OEM ECU has been binned in favour for something different from the norm. A Megasquirt ECU system is now keeping things in check.
Great power from a well looked after factory Nissan RB25DET with PLENTY of potential once the engine is forged and then the boost on the Holset HX40 can be really wound up.

The post TUNING THE NISSAN RB25DET (R33) first appeared on FC TUNING.

Blown gaskets here and there were naturally hindering the engines power but once sorted, serviced,the ecu reset and retuned this nice RB powered showcar was soon back up and running nice with plenty of poke.

Still a lot more to come but after the initial hassles in putting yet another skyline right, I knew the owner would be happy with the power, so forget chasing numbers. It makes what it makes, as I like to state.

Enjoy the video and remember to hit that LIKE button and feel free to SHARE your to your petrol heads friends.

The post TUNING THE NISSAN RB25DET (R33) first appeared on FC TUNING.

Nice to things simple on these OEM New engine setups, with just bolt ons. In this case a hybrid turbo and Apexi programmable ecu were down for some mild tuning. Issues with an actuator on the day prevented us from laying down some decent power, but it still a nice result and a good base to work from for a remap next session in the near future.

The turbo has plenty of potential and I can see from experience the this engine will make alot more hp and a huge increase in mid range torque improving the fun and drivability, which is what we all need.

Everything kept in check with an old Skool plug n play Apexi PowerFC ECU.

Looking forward to catching up Al and giving you well over 400 ft Ibs of torque to match.

Remember to hit that LIKE button below.

The post TUNING THE NISSAN RB25DET (R34) first appeared on FC TUNING.

Next stop 400hp+ – Big turbo or Bolt on Hybrid, Injectors, MAF and a stronger clutch.

The post TUNING THE NISSAN RB25DET (R33) first appeared on FC TUNING.

One of m favourite colours, Nissans Bayside Blue

Featuring launch control for some fast road action.

More upgrade to come in the form of our custom top mounted Borg Warner turbo kits.

The post TUNING THE NISSAN RB25DET NEO (GTT) first appeared on FC TUNING.

Fitting all those mods though is a worthless act unless the engine management knows about it.

Nissan Skyine R34 GTT featuring an FCTuningNistune ECU Solution and launch control to compliment all the modifications fitted so everything is balanced.

The post Tuning the Nissan RB25DET (R34GTT) first appeared on FC TUNING.

FCTuningNistune ECU upgrade was fitted to allow full tuning of the engine with the mild boost pressure applied.

A nice drive

The post TUNING THE NISSAN RB25DET (R34GTT) first appeared on FC TUNING.