Report from First Track Days at VIR

[JBH]

Two days at VIR North Course (my first 2 days with the car on the track)...here's the assessment of my Caterham SLR. To offer some insight to my perspective, I have logged many hours and laps on the same circuit with a Porsche 964 Turbo (heavily modified engine w/ 380 rwhp, tanny, suspension and brakes) and a vintage Formula Ford (1600 cc, 110 hp, ~1000lbs)

1. I was turning lap times of 1:43 by the second day, but I know I can get into the high 1:30s after a little more time with the car and cooler weather

2. The brakes and handling of car are superb. Handling is very neutral and predictable. I can improve my times by going deeper into some of the corners. I have yet to find the limit of those brakes. Absolutely no fade and the car was straight-line rock solid under braking.

3. A 6 speed transmission will take some getting used to. Too many times I ended up in fifth gear instead of the intended third. For racing, my preference would probably be a 5 speed. I also think the gear ratios don't need to be as close as they are. I would love to see the torque curve for this engine so I could get a sense of how to set the gearing.

4. On the straights, I thought I would blow past the vintage FF in my run group, but it took the entire distance of the 3000 foot straight to get by them and even so, I had to out brake them at the end. Three-quarters of the way down the straight, I am out of revs in sixth gear - roughly 125 or 130 on the speedo. I am not sure what I am going to do on Full Course - I'll be at redline half way down the 4000' back straight.

5. The foot box is tighter than I expected. On the street I drive in socks, but with size 11 race boots, it is harder to reproducibly and reliably heel and toe. I lose some of the feel for the pedals. Like the 6 speed, I am sure this is just learning the car.

6. It was over 100F on Saturday, but the engine temp never exceeded 105C. On two occasions, I came into the pits and noticed dripping coolant. Turns out the heat cycling loosened up some of the hoses. How lucky am I that none of that happened on the track? Great thing about a tidy build- it is easy to find and correct problems.

7. My car has muffler with a cat, but after the second track session, my left ear was ringing. You need ear plugs - I love the exhaust note, but the car is loud.

8. First session of Day 1, a beautiful Swift DB2 spins right in front of me. I stopped the nose of my car only inches from his side. I had visions of the weekend ending with me going home with a broken nose (carbon fiber) and split radiator. Last session of Day 1, I go a little wide out of roller coaster, up on the concrete curb and hit a cone. Damage shown in the picture below. I thought carbon fiber was stronger than steel. The cone got the better part of this encounter. Do you think the broken wing hurt my aerodynamics? :lol:

9. I try not to think about how vulnerable I am without any side impact protection. Arm restraints are a must.

 

Everyone stopped and chatted about the car - many asked for rides to which I was happy to give.

 

http://forums.rennlist.com/upload/rr_wing.jpg

 

http://forums.rennlist.com/upload/rr_body.jpg

 

[slngsht]

Great writeup!

[Al N.]

JBH-

 

Glad you had fun and only had minor wing damage...

 

Regarding the hoses...GET A RACELINE WATER RAIL ASAP. It will eliminate many of your hoses coming off the back of the motor. I don't have a heater, so it really was the perfect solution...keep in mind that it does have a provision for a heater. Not everyone is a fan of the Raceline, but I am and so are many others...some choose to do the little bypass line (See Bruce W.'s pix) , although I've made do with Raceline's suggestion of drilling a few holes in the thermostat to let coolant circ.

 

Some of the guys who race/auto-x have an alterate way of attaching the rear wings that doesn't pull rivets out every time you have an incident...you should find that thread or maybe one will chime in...

 

As for power/torque curves, you're in luck...find my dyno chart in the Tech section.

 

-Al