pilmat Real Racing Thread

[mike_gt3]

But there is nothing "wrong" with karting, in fact it's a lot of fun. Just don't think that because you are lightning fast in one that you can jump into a formula car and easily dominate

Didnt really noticed for the tire unloading, its good to know!
Im not really expecting to drive something else as i buy it only for lapping, ..and i think im already too old at 34 for a racing career


Thx for sharing again 👍

 

[pilmat]

What changes besides the tire selection tuning wise in raining conditions?

This is a hard question to answer as there is no simple "raining conditions". Things like how much rain, was the track well rubbered in before the rain, does the track drain well, temperature, etc really change how you approach wet conditions. Also things like does the car have downforce or not and what are the rain tires like (some are horrible...).

For a no-downforce car where the track has had some running in the wet (it didn't just start raining), the first thing we do is disconnect the rear sway bar (RARB) as traction will be at a premium. The next thing we do is "open" up the shocks (make them a lot softer) so that the car can pitch and roll more as the G loads will be greatly reduced in the rain. But if the car had a good balance before and the rain tires have a similar from/rear grip ratio, we don't do much else. Let the driver do all the work

For downforce cars, things change. Here we will again stay with the base spring/roll centre package, but will open the shocks and start putting on as much downforce as we can AND keep the balance in the car. Typically, lower formula cars do not have much if any wind tunnel information, so adding large amounts of down force by increasing wing angle can drastically change the balance of the car. The front wing's speed/force curve might be very different to the rear and then when you calculate the flat bottom effect in too, it is easy to change the low-to-high speed balance in the car (say it understeers at low speed and can have a lot of oversteer at high speed, or the other way around). So I work in small increments to keep the car predictable and in control.

When you get into higher formulas, like F1 or Indy, they have a lot of wind tunnel data and often have different pieces of bodywork to drastically change the downforce levels. The downforce is measured against the drag (loss of straight line speed) to get the best lap time. Their computer simulation models do all of this. In fact a lot of F1 testing is to prove/tweak the simulation models to best calculate needs at the track.

Not a straightforward answer, but there is a tremendous amount of variables at play here

Edit: I need to proof read for poor engrish before posting!

 

[anastasis14]

Understood

 

[deaconblues82]

Thanks for sharing this! It's fun to read some insider info and insight of what goes into engineering some of these racing cars.

 

[pilmat]

We raced in Road Atlanta this weekend with the F2000, qualifying 3rd for both races and we finished 5th and 8th. The 8th was due to a spin on lap one in the second race, but he climbed back from 26th on the spin recovery. Here is the car using a LOT of tire trying to make up ground:

We found a few interesting things on the Thursday test day. Without going into the details, let me describe to you how a typical test program goes when you are approaching a different way to load the car. As you can see by the above photo, the tires don't have the stiffest sidewalls. It's not a good or bad thing, just something you have to take into consideration when working towards an optimized set-up. The tire also has a very short life span. We are getting to it's serviceable life in 4 heat cycles, even if there is a good bit of rubber left on the tread. Add into that equation that we only have 6 tires available for 2 qualifying sessions and 2 races. So you are very likely to get to Race-2 with 2 tires on their 4th heat cycle, and past their prime.

So one of my goals for this weekend's pre-race test was to keep the tires alive for as long as possible. And I wanted to do this by loading the tires differently than we have in the past. How do you do that? Well, the suspension has a "ride" characteristic where the springs are doing all the work (when both tires are working together, the sway bar doesn't do anything) and a "roll" characteristic where the springs and sway bar work in parallel. If you soften the ride characteristic, you will need to stiffen the roll to get the car back in mechanical balance. NASCAR went through a major settings culture change that they call big-bar/soft-spring for tuning the front suspension, what we're doing on the F2000 is the same thing but we go both ways depending on our needs.

As I've pointed out before, the car has cockpit adjustable sway bars. So we start with a spring change and start tuning the sway bar around the new spring. We also have different sway bars, ones with different centre shaft diameters, to keep the adjustments within a usable range. A typical spring change is 50 lbs/in, so if you were going to a stiffer spring, you would go from say a 600 to a 650 lb/in spring, and start softening the sway bar too. Well a 50 lb/in change upset the entire balance dramatically! We spent the next 3 sessions chasing the set-up to be able to see any difference in speed. We needed to go 2 grades of sway bar different and to re-tune the shock considerably, as well as change the aerodynamics on that end of the car to get the balance back. But the overall change was an improvement of over half a second And we could keep the tire wear and degradation to a minimum. We could not get another heat cycle out of them, but they were providing quick times right down to the end of the 4th heat cycle.

I've seen a lot of teams make one fairly fundamental change, not improve on the lap time right away and go back to what they had before. But the whole race car is a system, and changes in any area often affect a lot of other areas. Don't lose faith in a change just because it didn't give an immediate positive result. Often you will need to go down the road a little farther, keep your eye on the end benefit you are looking and watch for signs that things are getting better or worse. We got faster AND more consistent, but it took some time

 

[pilmat]

As a side note: racing is all about details. 95% of what you see on Sunday happens behind the scenes in careful preparation and forward thinking. Ron Dennis, love him or hate him, is one of the great minds of Formula 1, and his idea meticulous detail is to be studied closely by anybody aspiring to success in racing. Here is a wonderful interview with him on his return to F1: Ron Dennis interview on Formula1.com. I especially like the "true north" and ensuring distractions are removed from peoples work load

 

[pilmat]

A busy couple of weeks of building shocks and matching "sealed" shocks for oval and road course cars.

Also got into a new brand of dirt oval shock: Genesis. I've done some testing of these in the past, but now I have two customers running them. There are some really interesting features in them, but also one big "hole" in their tuning capability. This won't be a big issue to start the year, but when the tracks start getting dry and slick by mid June, I'll be looking to get this area fixed! I'll get some pics today of some different dirt strategies in our shocks, it's very interesting to see how we tackle dirt versus asphalt.

 

[JCH8r]

Very cool information, please keep updating.

 

[pilmat]

Very cool information, please keep updating.

I'd love to be updating more often, but sometimes I get swamped and others the info is a bit "raw" and in my shorthand

We froze our butts off last weekend at the first Canadian regional 1600 race at Mosport (officially called "Canadian Tire Motorsport Park", but everybody still calls it Mosport). The results were strong and good, but we missed something on Sunday and faded in the race from second to sixth. The forensics of the weekend are still coming together, and I'll share the process and we'll see the results in a couple of weeks as we are back there again for the next race.

The weekend started well on Friday with some really good lap times and the car had a nice balance, just a little understeer in the higher speed corners to better judge accurate corner exits. It was also rotating very well in the low speed right coming on to the main straight (it's called corner 5B).

Then Saturday, we had a very wet qualifying and slowly-drying track race. Also, the temperature was quite cold at 7 or 8 Celsius. The both sessions were good with a comfortable second on the grid and an easy 2nd in the race.

Sunday started with qualifying on a rapidly drying track. We erred to the side of conservative with a set-up for the mixed conditions and got 3rd. The race started well with a strong second on the opening laps, but we faded to 6th, suffering from understeer in the mid speed corners. High speed was good and we were very good in the low speed corners.

Monday was put-the-pieces-together time, which started with a data review. Nothing jumped out at us, the entry speeds look good and minimum speeds were only a couple of miles an hour down from Friday's well rubbered track (remember that the track cleans up with a lot of wet running, and will take a while to rubber in once the dry conditions come back). Next we turn to one of my favourite tools; video review. With drivers who are quite inexperienced, video will tell you a lot about how they are doing. Hand "language" is very important. Are they sawing at the wheel? Are they turning too much, not enough? Is the wheel feeding back a lot? Also, you can clearly hear throttle application and gear shift quality.

After doing a video review by myself, I tasked the driver to do himself too. I want him to compare his lines and the car's handling when following and leading the group he was battling with (it was a 6 car group). We will then go over his notes. He needs to see what was car and what was driver in the handling puzzle, as well as how he managed the drafting game.

Working the driver's in junior categories is the real secret to improving overall performance. The cars are pretty close, so any improvement we can make in driving consistency and feedback is going to pay big dividends. And getting the most I can from any driver, whether they are front runners or mid pack warriors, is one of the most fun parts of racing for me

Now I have to go build some dirt shocks and get my F2000 plans organized for Watkins Glen!

Race on!

Edit: one of the mechanics took this shot just before Sunday's race:

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[Mamba]

I only just saw this thread, great information I've always been interested in behind the scenes stuff but F1 teams are very keen on keeping that a secret. Thanks for sharing 👍