XRAY - Model racing cars

Was at a big meeting over christmas and got talking to a very helpful team driver that recommend the H quick roll centres and 1 hole rear uprights. I spoke to him about so many things I cant fully remember what the exactly did it terms of handling. I thought that they improved overall grip but could anyone explain how they do this, And also is the grip improved when the car is rolling into a corner at higher speeds or any speed within reason.
Cheers for any help guys

Sorted

So what were you told?

H roll centers increases the roll center compare to L roll centeres. Higher roll centers incerease car roll and that increases traction. However, H roll centers provides slightly less steering

Mid hole rear upright gives less traction, however increases cornering speed. We use mid hole uprights on high traction carpet and asphalt tracks and tracks with long sweepers where mid corner steering is needed.

Basically what Martin wrote.

H roll centers provides little less in corner steering than H roll centers