Quale cupolino o spoiler???

Anche io proverei prima con i rialzi, non costano niente e potrebbero risolvere molto.
Se no andrei su un deflettore con 2 punti di ancoraggio: intanto è più stabile e vibra meno, poi lascia passare meno aria tra lui e il cupolino nella parte laterale. Alla lunga uno con un punto solo centrale potrebbe farti venire il cupolino.
Tipo questo per intenderci:

https://www.ebay.it/itm/313091435722?_trkparms=amclksrc%3DITM%26aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20190917065201%26meid%3Dc6ab0ccc844449faa641b9d8f0f16cdf%26pid%3D101096%26rk%3D9%26rkt%3D12%26sd%3D154799135047%26itm%3D313091435722%26pmt%3D1%26noa%3D0%26pg%3D2332490%26algv%3DSimplAMLv9PairwiseUnbiasedWebCpr08MlcGreedyV3&_trksid=p2332490.c101096.m3021&amdata=cksum%3A313091435722c6ab0ccc844449faa641b9d8f0f16cdf%7Cenc%3AAQAGAAACEKgDm04FAZEoq3RVQwhFgCvCuU0X8ubPootJnwx02pE7hcyzqUjiajOTC3Lci48dFG%252Fh7fklVzdjIU4wUGeD7y2%252BTaURLeHWKM9gzkf7Hc1FpDmY8CP0n%252Fa2%252B%252F9r0fp0J3QwBy7DAOwW8AuMSMy5BaRFGScCwcmSNVHH60rdgIMrOwRs%252BxJVFdA6jbUA%252BxAP0hZ%252BHTdDehoGaFFtH5vA5IgNjaCmsS9fAZwVfDmE8tde3q7tT1%252BFZaGP6qoJqloByYyZ03ey3EptNzXgwcwe6FHgO0vsOi8KHm1Fb0ibUfUYGVL6ahqsZ05chYam%252FbvIDDx33HBtWMdsQ9Bsv9032fPW8gkGxgJ%252BlER0CLUdnZn9OsBaOhTeLaU22Ggm8Sqz6G%252Bl4tlakDnubieF74tIjFcw0NjZYWemRpQPqaDujlTxdBBX7AtOIK8eq9xueq1QXfHzHyR980%252FRfzXQW4cCDyXVscbffjcZETsHR1%252BocuZiCAf350kD9jQynzqqsnLNmdzF7sIihoOGKEYDBAM3dsq6JWgFSsVjoIdWgxW2sEGUdedMm%252F12UAfRpdSSaiVtbesH5i8C6db0YFQJWhcKkKke1hGyN8vJaAVMARU9KnE8Qx42u0VYnvhY7ZCox2y%252FKqaUl3SbPV7TgJhRf4%252FWkfWcYnSpReRBSFlib3ngxGF9fd374NSyQb8vCMjcCmhJbg%253D%253D%7Campid%3APL_CLK%7Cclp%3A2332490