Downforce Laguna Seca vs Sonoma

[Dee]

Driven for many years in open wheel @ Laguna Seca NEVER driven @ Sonoma , I plan on running there in Oct are they about the same on basic set up and Downforce any thoughts

Thanks,
Dee
RT 5
RT 41

[Fmracerbob]

I've run both tracks since the early 1970's, have a shop at Sonoma for years and tested, coached and raced all kinds of cars and drivers over the years. Unlike Laguna which has two serious straights, the main straight and the run up the hill from T6 to the corkscrew, Sonoma doesn't really have a straight. Laguna is more - approach the turn, go through the turn and then pretty much a straight run to the next turn. As a basic yardstick with say a FM we tend to run a little lower RH and less wing by a degree or two than at Sonoma.


But Sonoma is very different. The track is basically one turn after another, get one wrong and you pay for it in the next. It will wear you out, get in shape before coming. Here you need a bit more ride height and softer shock settings to handle the curbs and the roughness of the track. Shocks are much more important as well as spring rates for Sonoma. A very stiff, low setup will cost you. Too soft and you will be bottoming.

Most FM's will just about max out the wings, I've seen from 7 to as much as 9 degrees on the rear, which is a lot. It depends on how much moving around in the turns you can handle. With the vintage F1 cars we pretty much go max on the aero settings, think more like Monaco.

The first half of the track is the technique part, lots of up and down hill with various degrees of banking. The track should not be approach as if it was flat, it's not. There are little peaks and fall offs just between turns or in the turn itself. Reading the topography of the track surface itself is critical. You can't treat it like it is a flat piece of paper and draw the optimum line though a corner.

The second half, from T7 to T11, is where the speed is found and what separates the men from the boys. David Brabham commented if they could make a car (Nissan GTP) work here, it will work anywhere. James Weaver said T10 is the most challenging in North America.

If you are serious try to attend an event here or get all the testing and practice time you can and be prepared to alter your setup, top straight line speed is not the key. It's speed through the turns, especially entry speed that rules.

A few items to consider.

There are two "esses", turns 3 and 3a and turns 8 and 8a. In both cases don't try to use the typical "straighten out the turns" line, the key is exit speed from the second half. You sacrifice the entry to the first half to maximize the exit on the second half. Turn 4 is one of the few classic passing spots.

The run from T11 through the S/F and up the hill to T2 is not as obvious as it appears. There are real elements to the track surface that negate trying to use all the full width of the road after the S/F for entry. The general rule is "mess up in T1, crash in T2". Study the track surface carefully. Braking for T2 is also important, again study the raise and falling of the surface as you approach the turn. Remember trying to corner while cresting a hill is not the best way to do it.

And finally, the run from the exit of T8a through T10 is the single most important part of a lap. Entry speed to T10 will challenge most drivers but is is where time can be had and passing can be setup for T11. The turn is faster than most drivers think, but it will definitely challenge.

Everyone should try to experience Sonoma at least once, as a customer of mine once said "this place has one of everything !!"

[Dee]

Thanks for the info I spoke with davy jones ( I will be driving his 82 Ralt) he said just about the same. my co driver John Morton
totally agrees but what does he know

Thanks Again for your input,
DEE