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T51R not hitting full boost

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Hi. I am tuning a 2.0 4g63 evo 3 using a t51r turbo and the boost seems to climb without hitting full boost at 3rd gear. I am aiming at 3 bar or 45psi but the engine only ever got to 2.5 bar at the end of 11k rpm. Is it because the final drive is too long? Because the car came with 3.866 gsr final drive. The engine is using gsc s3 camshaft and 20% nitromethane mix inside the water methanol injection tank. This test was done on the road and not on a dynamometer.

It's a big turbo. They have inertia to overcome as well as requiring a certain exhaust flow/energy to drive the compressor side. I would be making sure you have the following: Large intake filter area or mesh, ambient air to turbo, large intercooler, no intake leaks, external/separate/divorced wastegate, 3.5 or 4 inch exhaust. You may have to drop a turbine housing size too. Are you well away from being traction limited with that boost in 3rd?

You may find you simply need to go to a more modern turbine and compressor in that frame size to get what you want.

There is no exhaust on the car. It was like 8 inch after the turbo and straight to atmosphere. There is no intake pipe as well. Just mesh. Yes im well aware with the no traction in 3rd gear. But this is a realy long gear it hits 240kmh in 9k rpm. Ive seen andre using it on the docile. Would love to hear his opinion on this

You need to give a whole lot more information on the vehicle, so the Mitsi' gurus can give some suggestions.

Intake and exhaust manifold details, charge cooler details, head work if any, lambda and EGR data if available - the former may be a problem if it's too close to the end of the exhaust stub, etc. have you any data on the charge pressures through the intake side - you can lose a LOT from poor plumbing and charge cooler selections - oh, what throttle body/ies are you using?

As mentioned, there may also be problems with the size of turbo' you're using, from both inertia and internal leakage which will delay the boost thresh-hold. if you're using a big hot-side it may just not have the gas flow to drive the cold side - exactly what are you using?

Oh, I should have asked this first, what sort of power are you getting - "boost" is basically a measure of resistance to flow - back pressure if you like - if the engine is able to breath well enough, you may not see the "boost" you expect, as the engine is actually using what the turbo' is supplying.