- Serpent S411 - Martin Crisp - St Louis - Hudy Race - 08.01.2012 -

I had the opportunity this past weekend to race at the Hudy Race in St. Louis. It was not a big race, but Paul Lemeiux was there along with Andrew Hardman and Drew Ellis, so it was an awesome chance to get some serious testing/tuning done.

The grip was good, and I tried many variations of setups. The car was awesome through chicanes and on corner entry, but lacked a little steering mid corner and corner exit, but it is very close to where I wanted it to be. Paul's best lap was 9.2, Andrew 9.3 and I was 9.4. Paul and I both broke in the main (the boards did not move and the track had no flappers), so Andrew took the victory with Drew second, but more importantly it was a great test session and a track with grip similar to the snowbirds race.

This setup was easy to drive and very consistent.

PDF File

Martin, your latest setup you had tried at the Hudy race - can you confirm the rear upper link position on the rear hub? The picture looks like its the inner, but its listed as the outer on the setup sheet. Also, the the 2 hole and 3 hole pistons in the rear?

I used the longest possible link in the rear of the car to free up the rear a little. The longer link gives less camber gain and also lowers the roll center a little bit. The longer link also means the roll center changes less as the car rolls, making it feel a little more consistent.

When I got back to my home track I ended up using the outer holes on the rear arms. I had should have made that change at the hudy race, but never got around to it with all the other changes I had made. The rear was a little too soft when using the inside holes making the back of the car roll too much relative to the front on corner exit. Using the wider holes in the rear made the corner exit more stable.

I see a lot of the setups seem to like using the yellow spring in the rear and the orange spring in the front, but when I tried that I felt the car was terrible in the middle and exit of the corner. I have tried a lot of different spring combinations and really like the gray spring on the rear and the black on the front. If the car starts to traction roll and I can't resolve it in another manner, I might use the grey on the front, but doing so will take away some mid corner speed as the chassis will rub on the carpet.

I also tried a shorter link in the front this past weekend at my local track and got the results I expected, due to resulting increase in camber gain and roll center in the front. The car had more lateral grip at the front of the car giving it more steering, but I think it was a little edgy and with the extreme grip levels at our track, the car would start to traction roll or bicycle more easily. So I went back to the longer front links. Next weekend I will try the shorter link but add approx 0.5mm of inboard spacers to keep the roll center low and see if that helps.

I am really starting to get a feel for this car...and love it. I am looking forward to the snowbirds race. That race is very competitive.

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