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Hey, just wondering what the average amount of boost you can run (standard computer, 25 turbo, cooler, exhaust) before the car will hit fuel cut & not boost properly.

I’ve just installed a boost tee which is set to 14 PSI & I’m wondering if it’ll likely need adjusting to a lower boost setting.

Cheers,

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rb25det NEO cuts out at 14-15psi. thats when mine cut out.

and at the 15psi mark, it will also go into R&R around the 5k rpm mark every now and then.

mine ran into 2 problems when i hit 15psi, it either cut out completely and it felt like i drove into a wall when the fuel cut out,

or the other problem was it just stopped accelerating past the 5k rpm (i could keep foot on accelerator but it would not go past the 5k mark), i think the R&R kicked in then.

The ECU decided at random what it problem it wanted to choose.....

so i replaced the stock ecu with a power FC and run between 14-16psi depending on the day

Pretty certain RB20s don't have a fuel / boost cut mechanism. Other than the ceramic wheel shattering if you consistently run more than about 14psi boost.

pretty sure you are right on this.

best thing is to put it on the dyno and see what is going on with the afr's to make sure it's not leaning out

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