Desync issues on server?

my friend and i always have really horrible issues with my car being at least 100mph faster on his end
example: he was driving a GTS Scintilla and i was driving a v6 Sport Pessima and i gave him a head start by 5 seconds and i still caught up. he tabbed over to me said i was going 190mph on mine i was going 100

i dont think that this is related to the server or beammp in general. If you two start at the same time and you go faster then you go faster. Maybe he didnt floor the throttle, maybe hes playing in slow motion or lastly his game is lagging so bad that hes slow just because of that. Otherwise id like to see a video of that happening at best from both sides, yours and his.

we had people in the beammp set up a server for us specifically to test this and a moderator even confirmed we both full throttled. he is not in slow motion he does have a low end pc though so maybe its lag?

If hes running less then 30fps then its lag what causes him to be slower