Boost 2ª / 5ª

[pepifebles]

Hi guys,

I think that my turbotechnics S148-3 could reach max boost quicker. 5ª gear get 1 bar at 3100 rpm (I'm happy) but 2º gear I need 4100rpm to reach 1 bar. What I mapped wrong?? Log attached 2ª and 5ª gear.

[gregpe]

HI
Turbo is not a supercharger and in not depending only on RPM but also on load so on 2nd gear you have less load on the engine that 5th that's why... due to ratio of the gearbox..
so is pretty normal that you get more boost on 5th than 2nd..

[pepifebles]

HI
Turbo is not a supercharger and in not depending only on RPM but also on load so on 2nd gear you have less load on the engine that 5th that's why... due to ratio of the gearbox..
so is pretty normal that you get more boost on 5th than 2nd..

I know that its normal, but is not much difference??

[ren]

Perfectly normal. You can compensate with more duty, but in this case it will make no difference.

What engine / fuel is this? Looks a bit lean for a turbo engine.

[pepifebles]

Celica gt four 3sgte. Ron 98. 2º gear seems little lean but think its ECU read speed. In 4ª and 5ª when boost 11,7/12,00

[RHD]

engine load will be the same in every gear, the engine has no idea what ration is in the gearbox or what gear its in. Boost can only be affected if the per gear or vehicle speed boost settings or some other settings are active etc.

[pepifebles]

None of that has been modified. Vehicle speed boost its 100% to all gears. I suppose that is the normal work to this hybrid turbo

[ren]

engine load will be the same in every gear, the engine has no idea what ration is in the gearbox or what gear its in. Boost can only be affected if the per gear or vehicle speed boost settings or some other settings are active etc.

This is not correct.

You will *not* be able to generate the same engine load that you can in 5th gear in 1st gear.

[gregpe]

engine load will be the same in every gear, the engine has no idea what ration is in the gearbox or what gear its in. Boost can only be affected if the per gear or vehicle speed boost settings or some other settings are active etc.

Engine load depend of gear highly easiest example on what gear clutch start slip first ? 1 st or fifth? And how much boos you can generate with no load?