Now, let's say i'm driving at 6th@ 1800rpm, if i go pedal to the metal, car starts to accelerate smoothly, but then around 2.5k rpm some chain rattle starts, and right at 3k rpm (still full throttle) engine knocks and some breaking sound comes from exhaust (something burning in catalytic converter maybe?).

now, i have new hpfp, new injectors, car's is @70k miles, oil is new (castrol 5w-30) and i'm using some cheap 95octane (europe octane) gasoline. i'm gonna try this with better gas but i don't really think it's related with that. it's hot around here, so it might be related with high intake temperatures maybe?

anyone had a problem like this?

'09 MCS

 

Two things: Full throttle at 1800 rpm in 6th gear is risking engine lugging which can cause all kinds of mechanical damage.
Second, the notorious timing chain problems with that particular engine may well be the problem. Either way, if you want rapid acceleration from 35 or 40MPH, downshift to 3rd and use the torque curve.

 

Oil level? Carbon build on valves? Toptier gas?

 

Oil is at max, never done anything about carbon buildup. So it's possible too.

 

I'd try the better fuel....as you as "cheap 95" in euro numbers..is about 91....IF it is on spec...but some dealers are less than honest...
High load...low rpm. High temps and super knock...pretty classic octane issue. First...try better fuel....
Then look deeper if needed.
You may find high octane is needed in summer....and mid grade in winter....rpms seem a bit low..but a gen2 owner I am not.

 

My MINI was doing the same thing. Dropped it off at the dealer on Friday and they confirmed the timing chain tensioner was out of spec. This is the second time I have had to have it replaced.

 

Yeah....add chain noise to the post...
I would not mess with it....serious damage can result from a timing chain issue...
Missed that bit of info in the op....

 

If it's tensioner, it's gonna be my second too. 2 tensioners in 70k. Good engineering really.

 

Ive only got 39k on mine. Luckily, the dealer is fixing it for free even though it is out of warranty. Mine was also built after they had the "fix" for this issue too.