Sticky tires

I tried two types of Hoosier slicks on the last two Philly region autocrosses. The first set were 20.5x7-13 R35A compound tires. They are made for a 6"-8" rim, but mounted okay on my 5" rims so a I gave them a try. It was a cold day and everyone complained of poor traction. My times were competitive but traction felt worse than in previous autocrosses with street tires... could have been the due to the conditions but I wasn't impressed.
Last weekend I tried a set of 22.5x7.2-13 R25B compound tires and the grip was excellent. Since it was a warmer day and different course it's hard to compare tires, but I think I'll stick with these for autocrosses until they wear out. I contacted Hoosier tech support and they recommended 20.0/8.0X13 R25B tires, which are almost identical, just smaller diameter. Getting the car closer to the ground can only help so I'll keep an eye out for a set of these to try next.

Despite being listed as 22.5x7.2 they measure almost 10" wide and would have rubbed against both front and rear fenders, so I had to remove the fenders to run. Looked a bit strange without rear fenders, but added lightness.

New Chapter...

...or maybe another book. When I'm asked if the car is finished, I'm not sure how to answer. I still spend time on the car when time allows, but the focus has changed from fabrication to preparation for autocrosses, debugging, tweaks, and thoughts about upgrades...I was warned that these projects never end...

The good thing is that I get to drive it now, including occasional trips to work when the weather is nice. Here are some pictures taken next to Steve's Jeep . We both started and finished our projects about the same time. Even though our projects were very different, it helped to have another car (Jeep) nut around to bounce ideas off of and stay motivated. Steve didn't cut any corners and the end result is one of the nicest CJ5's I've seen. Both are purpose built vehicles, though for very different purposes.


Driving impressions of a BEC Se7en:
Having participated in FSAE when in college, I had some idea what a car powered by a motorcycle engine would be like. I had also read about driving experiences of others who had BECs. Everything you hear is true.

If you're looking for a cruise around in, take the wife or kids for a spin, car with manners, a BEC Se7en isn't for you. If you are looking for a road legal race car, you may want to consider a BEC.

The bad:
BECs are clunky. Motorcycles have rubber cushions in the rear sprocket that soften gear changes and changes in speed. BECs have a lot more mass in the drive line, a differential that has play, and in most cases, a hard mounted drive train with no rubber cushions. When you shift into gear, or get on or off the throttle there is a clunk. You can minimize this with a "cush" drive shaft and driving technique, but never eliminate it (so I've heard). On a positive note, when wearing a helmet and driving all out you never notice the clunks : )

Driving on the street requires restraint. I have a stock muffler, but open intake. Induction noise makes it louder than an normal R1. At WOT, the noise will attract the attention of anyone nearby. Not good if you want to be a good neighbor, or try to avoid speeding tickets. And, it only takes seconds until you are above most speed limits, so the thrill of acceleration doesn't last.

There are a lot of hazards on the road for low ground clearance cars. My car has about 3" of clearance under the oil pan (note to self: fabricate sump guard...). Road kill, speed bumps, potholes all can cause significant damage. This makes it foolish to drive fast around blind corners and over hills, roads that would be the most fun to drive in a Se7en if the hazards didn't exist. Add the thought of an SUV pulling out in front of you...

The good:
If you have a place to drive all out...like an autocross, hill climb, or nice roads with good visibility...the responsiveness is mind boggling. From 7k - 11.5k rpm the engine just pulls, the shifts are quick, and the car goes where you point it. I'm still learning the limits of the car, but in reality the limiting factor is the driver. Not a problem, I don't mind working on that : )

I'm getting more used to the exposed feeling, and when the weather is nice and I need to recharge, I drive the Se7en.