please need help: F4RT vibrating hard at 5000 rpm and over

hello,

i hope people can help with my problem.
i know its not a clio but still a renault sport.( have 2 clio 172 aswell lol)

i own a megane 225 trophy and by my known it never had this issue .
its been a long time a went for a spirited drive (due to weather) but if i rev to 5K rpm and over the engine starts vibrating quite hard.
i own the car for more than 5 years and by mine known it never did this.

maybe its normal cause 5k and over is quite high rpm and its a turbo engine (lower rpm powerband).

i always put premium petrol (98 octane ) in the car sometimes with injector cleaner.
just had a new cambelt with renault locking tools. injectors never been replaced by my known , and coils i dont know. spark plugs are like 10000 miles old at max ( need replacing at 30k)
it doesnt use oil or coolant last time i checked.

engine mount at cambeltside has been replaced 3 years ago ( or so)

engine mods : open airfilter, mid silincer delete (for over 5 years already )

i think its something engine related and on 1 hand want to keep testing it what it is, and on the other hand i dont want to blow it up.
so i come to here for advice cause some of you have more experience multiple engines etc

hope someone can help me .

greetings marco

addition : the exhaust sound at idle sounds smooth not spitting

Dual mass flywheel at a guess.

As above knackered dmf at a guess. The engine should rev to the limiter without issue.

thank you for the fast awnsers great.

strange i didnt consider this cause a dmf should make noise when starting or at idle right ?
2 its not the thing i looks forward to changing lol

i taught someone is gonna say injectors , cause i read the sometimes fail eventough its not spitting as far as i know.

is a dmf a common fail on a f4rt ? how can i check without taking the gearbox off ? normally with a sound you start the engine or something and hear it.

bearing issues /rod issues ? i dont think i hear a sound .. its just like it vibrating like its falling apart almost and bit slower climbing in revs it looks like ( could be mistaken )

Dmf fail is common enough on them. I have a 225 breaking that vibrates from low rpm when revving on idle, dmf issues.

Bad injectors would cause a misfire not vibration. It wont be bearing related, when they are failing the engine revs ok with audiable knock, not vibration.

ok didnt know that its common.

yeah but bad injector can to have a strange spray pattern wich on high revs can be 2 slow to fully function and mix with air. and so engine starts knocking slowly

but a bearing issue to can vibrate but like you said with a loud noise.

the engine does rev ok (goes to 6k higher i didnt dare ) but it just vibrates and looks like it slower in revving ( could be me)

i would think about dropping the box , ( hate the job)

tried it today to test the dmf but you need to press the clutch pedal fully in to start ( in gear) . i wanted to let it just grab so the dmf stays to one side.

it does make a noise sometimes with starting but i think its a engine mount or suspension cause it makes the same sound when i go over a bump turning left.
tried to find the play but cant find any in suspension . maybe you have an idea about this 2. it 2 has this problem for years

love youre projects btw i have followed some like youre kangoo 3 F4Rt. nice toys you have 2 megane 225 and a meg 265 right ?

thank you for all the advice till now

Its difficult to diagnose stuff like this without seeing it in person. It sounds like you have a misfire