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Once my car is tuned with the 10 psi pulley, will I be able to revert to the bigger pulley and not touch the tune?

Sounds OK to me in theory but I'm no expert.

Thank you all

With the NC and EcuTek tunes AND a 3bar MAP it's possible to finalise a tune then change pulleys whenever you want and the tune just alters for boost.
Don't know if that's possible with yours, I guess it will depend on the capability of the ECU

Thanks Sailor.

NA6 MX5. MP45 SC from a mini, MS2 ECU and I have 2 Kavs pulleys.
10psi being the small one and the bigger one maybe 7psi.

Figured if tuned for 10psi, I'd be able to swap for the 7psi pulley without changing tune, as it would already be tuned up to 10psi.

Is this correct or will it be necessary to have 2 maps?

It depends if the compressor efficiency significantly changed at different pressure ratio vs flow's.

Ie, you will need to swap the 7 psi pulley on and check the tune with a wideband, and check the plugs for knock to be sure. but why would you want to swap to a smaller pulley?

NitroDann wrote:It depends if the compressor efficiency significantly changed at different pressure ratio vs flow's.

Ie, you will need to swap the 7 psi pulley on and check the tune with a wideband, and check the plugs for knock to be sure. but why would you want to swap to a smaller pulley?

Thanks Dann.
Was thinking of getting the missus into motorsport and liked the option of less boost as a learning get curve.

On a car with a linear torque curve less boost cant and wont help the car to be safer or less intimidating. I might agree with going to a smaller turbo on a laggy torque monster but with a blower you are causing yourself headaches for no reason.

If you REALLY wanted to lower the performance for her, Id install a throttle stop. Just a bolt through the floorpan going into a nut welded to the body, you can raise or lower the throttle stop in 30 seconds with a spanner and its infinitely adjustable.

Dann

Would it be an option to load a detuned profile into the ECU when your wife is learning?

there is no such thing as detuned, there is the right tune, and there is the wrong tune.

Dann

Thank you gentlemen.

Im guessing the throttle stop is better then a Rev cut as the car is less likely to bog down?