[Backwardsman97]

Try this on for size.

pawn Код:

forward BoostTime(playerid);

//When you start the boost
SetPVarInt(playerid,"BoostTime",SetTimerEx("BoostTime",2000,1,"d",playerid));

public BoostTime(playerid)
{
    new
        Float:x,
        Float:y,
        Float:z,
        Float:v = GetPlayerVehicleID(playerid);
        
    GetVehicleVelocity(v,x,y,z);
    SetVehicleVelocity(v,x*1.3,y*1.3,z*1.3);
    return 1;
}

//When you stop the boost
KillTimer(GetPVarInt(playerid,"BoostTime"));

You'll probably want to play around with the time on the timer so he doesn't just constantly accelerate until he goes way too fast.