Greetings and salutations again

After a while, I have another question
I wanted to by new wheels for my 3.0 V6 Omega. Current ones are 195/65/15 on steel rims.
When I arrived to seller, he was surprised I am using this dimensions. He told me, that this engine must burn those wheels very easily. I didn§t try it yet, so he started his Omega (also 3.0), steped the accelerator and disappeared in smoke... (he is using 215/55/17 on alloy wheels).
I can try as hard as I can, but all my result is only seesaw - the front goes high while the back sits down.
The same is in corners, all I can get is little squeek when accelerating during cornering.
I donīt want to torment it, or buy a new tires every month, but I think 155kW should be able to smoke with any driver behind the wheel. So I would like to know, where can be the problem? Is it in me, that I am doing something wrong? Or might there be some problem with Omega, which is holding her back?
I have to say I have bad exhaust (the middle part has holes in it).
TCS is off (the TCS lights is on).