Classic MY95 with a Ninja sports decat and newage TMIC fitted running a Z4 ECU unmapped on v power

no leaks from downpipe/decat pipe and cant see a leak from the turbo to TMIC pipe yet on full throttle giving it some WOT the stench of fumes was quite bad,windows were up.

doesnt do it on normal driving,never used to do it (on old slanted TMIC) and didnt do it a few days ago,im sure it didnt,maybe i didnt get upto the same speed as today

anyhoo,any ideas

 

My old MY96 used to, and it was oil from the driver side rocker cover gasket dripping onto the upipe causing the fumes.

 

Thing is,this is exhaust fumes,not an oil burning fume etc
smells just like your behind the car but inside it

wondering if its the door seal/rubber,get alot of wind noise at high speed and from the car ha !