TRF421X Initial Setup on Medium Grip

As already promised, here I post some comments on my recently finalised setup on my TRF421X iN Andernach on Medium-High Grip conditions (more medium, than high). Did it make sense to develop a setup for medium grip? Does it make sense to run through the rain without getting wet? Maybe? Or not?

Here you can see my lap times throughout the whole day of 2nd May 2026. A clear trend to lower lap times can be seen, as my confidence rised continuously. The last 3 batteries fest best and I got clearly convinced: Even on Medium Grip and some major tweaks TRF421X is better than TRF421!
However, on low grip TRF421 was 0,2sec better and more save to drive (conclusions of both practise sessions in April 2026). However, I compared PA-CF suspension arms to each other and had no comparison to the softer ones from PA-GF.

I have never had a car with that much amount of initial steering and in the same time low drag during cornering. That means, that the car was not loosing as much speed, as I was used to with TRF421. Most probably the ball bearing drive shafts did some contribution to it.

On 2nd May I was mainly swapping different topdeck configurations and was permanently comparing TRF421 to TRF421X as I wanted to find out the core differences between the chassis (not the suspension arms). 1mm lower mounted motor sounded good, but now I know, it`s definitely a step into the right direction, as I was never able to make a 18,6sec lap before during a practise session in Arena33.

Regardless of my driving (which by the way I don’t judge to be too good!) or the fact, that a Modified Combo was mounted on my car I feel extremely positive also for stock classes and am looking forward to see some TRFworkz Teammates to achieve good results anytime soon. In May there will be some more testing sessions and knowledge-transfer sessions before slowly heading into the European championship preparations for Luxemburg, which will be my personal race highlight of the year.

Now enjoy the pictures and one video. Also my setup is posted here (besides the LMH one from Simon Truong with his TRF421): https://sakaguchinetshop.com/shop_content.php?coID=11