- Schumacher Cougar SV - Tony Newland - Utah States Champs - 13.11.2010 -

The last couple weeks have been real busy getting the cougar dialed in. Emailing back and forth with Tom Cockerill, Robin Schumacher and Mark we have all been working on getting the car up to speed for the USA tracks. My setup has changed so much it didnt make any sense to post anything until we came to a good balance on the car. I've probably ran between 150-200 packs in the last 2 weeks and feel like I'm very familiar with the car and what changes do what. This is the first mid motored car I've ever raced so I went through quite a bit of learning at first. Our track is like many, moist dark clay that takes rubber well, doesn’t really wear tires out fast, will blow out foams before the tire is worn... we run Pink Losi tires, gold Jconcepts and MC PL's. The more traffic it gets the faster it becomes, it can pick up as much as a full lap when the groove comes up. If we have a race with 200+ entries we will end up with slicks by the mains. This weekend was in the middle... excellent high bite with ghost pins with no chance to run slicks. The pace we run here is at a national level every week. Dustin Evans, Matt Chambers, Scott Brown and Kinwald all have to get flawless runs to TQ. Our club races consist of 6mins of laps within 2-3 tenths of a second per lap, any more and your mid-pack. Our top 3 are A mainers at Cactus, Nats every year and worlds team members. A-mainers from cali club races are B main here. Just so you have an idea of the pace and level of drivers in our mod classes.
I struggled with rear grip with the car since day one, that has been solved. Consistent steering response throughout the corner was also something we needed to work on. In Europe the tracks are typically turf with wood jumps or outdoor on grass with a flowing layout. Here we have lots of 180 turns and jumps that get beat up from SC trucks. In the high speed and sweeping turns the car was great but 180s where the car crawled through the corner and needed instant rear grip to accelerate it lacked. After a few bottles of oil, numerous piston and spring changes I've arrived at a shock setup that should be pretty universal, depending on temps of course.

Front:
4 hole
35 losi oil
4.0 spring
2x .030" limiters
unscrewed 2 turns
inside on arm and tower

Rear:
4 hole
27.5 losi oil
1.6 spring
1x .030" limiter
inside on arm
middle on tower

Everytime I tried the outside on the arm is made the rear too stiff and decreased rear grip overall, forward bite and side bite. The inside hol on the tower will increase side bite quite a bit, but will not square up exiting a corner very quickly... middle hole is consistent entering the corner and consistent squaring up on exit. Never tried the outside hole as I don’t think we have a soft enough spring.

I have shifted both front and rear arms around several mm to test wheelbase and dogbone angles.

The best balance has come with the front arms flipped AND dremeled to move 1.6mm forward. Our car is much shorter than say a B4... almost 1/4" stock. The rear arms I settled on 2.5mm forward and rear hubs forward with the diff low. I tried the diff high and it may have added some rear grip, I didnt really notice, I did notice it made the rear end really inconsistent how the car would enter and "drive" through the corner... unpredictable and inconsistent. The amount of dogbone angle when you move the arms and hubs to this point really adds alot more grip. The fact that we use universals rather than CVDs limits the amount of grip we're able to get from the drivetrain. CVDs add a ton of grip in any car. Might be something to visit in the future with a USA specific car kit.

I also have added 2 brass bars that HPI makes for touring car balancing. they weigh 11g each and are about 3/16"x3/16"x1 1/2" and fit perfectly in front of the motor with the stock aluminum standoff screw holes and places the weight as far back as possible. I would also like to see a brass weight that could bolt to the stock sway bar mounts as we will virtually never run a sway bar here.

I also have tested several chassis plates they have sent me. I like the S1 the most. It flexes alot and I think makes up for the weight distribution and wheelbase differences.

This weekend at our state champs I had the fastest laps in the main by a few tenths and ran a few of them. Traffic took me out of a podium but 4th was a victory IMO with the amount of changes and testing I was able to do recently. The car has come a long way and the lap times have come way down from where they started.

One more thing I forgot... ride height. Ride height on the cougar is critical.

I run mine 22mm F&R strictly.... I measure before and after each run, on a car with carbon plates that are bolted on verticaly the ride height will change from time to time. To set it accurately you must have a gauge. 1mm vary F-R and overall has a dramatic effect on the handling. So spend some time fine tuning your handling preferences with this accurately and you'll get consistent results and performance.

1mm lower in the front than the rear will increase corner entry steering greatly and 1mm lower in the rear will do the opposite. Without changing shocks and/or links this is a huge tuning adjustment.

Can you explain the reasoning behind moving both the front and rear arms forward? I imagine that shifts all the weight of the car rearward... Wouldn’t running your rear shocks on the back accomplish the same kind of distribution?

I moved the rear arms forward for 2 reasons.... yes it will shift the weight slightly. Not as much as you would think though. In on-road we change wheelbase and on the scales its usually less than 20g from one extreme to the other, so the static weight change is minimal. The second and more important reason was for more dogbone angle. This will cause more bind in the outdrive and result in more traction. Our car uses universal drive axles which have much less bind than CVDs, therefore have less traction.

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