Rams Eye The Track Guy

C7 Corvette Grand Sport... doing a burnout with a proper diff - Graham MacNeil  © I wrote a tech post comparing various open and limited slip diffs for a comparison and I found that a lot of people were asking questions. To simplify and make it easier to read, I decide to break them up for a future tech article about handling. Make sure to stay tuned for two posts on limited slip diffs this week!. WHY DO YOU EVEN NEED A DIFFERENTIAL? A differential's job is to allow two wheels on the same axle (or two axles in a 4WD drivetrain) to spin at different speeds so a car could smoothly go around a corner. Why do the wheels need to spin at different speeds? Each wheel on a car has to travel a different path to reach the end of the turn. You can see that for yourself every time you drive on snow covered roads or muddy trails. Four different tracks by four wheels/tires on one car going around a turn - Rams Eye The Track Guy  © If you take a turn, you'll see that each whe...

It went 11.77 seconds to be exact and past the traps at 116 mph and that's with minor modifications. The modifications were courtesy of the folks at Ford Racing. They recently got a hold of three 2015 Mustangs, one with the 2.3L EcoBoost engine making 310 hp and two GT's with the 5.0L V8 making 435 hp. The power modifications are minor for two of the three Mustangs. The 2.3 EcoBoost gets a "Prototype Off-Road Exhaust" which most likely means there are no catalytic converters or "cats", a more free flowing exhaust and a tune. One of the GT's gets the same off-road exhaust treatment and a tune plus "ARH Cobra Jet Long Tube Headers". In the video, they say they did "a few changes to the air intake system but basically these are close to what any consumer can buy" so they may have included a K&N drop-in filter which FRPP Performance Packs for the 2014 Mustang GT included or an aftermarket CAI with a cone style filter....

I've been a huge fan of Michelin PSS tires and exclusively bought them for the Mustang over the last four years. So how did I end up here? This year, I was hugely interested in trying an "R-comp" tire. I had my eyes set on Bridgestone Potenza RE-71R's for two simple reasons: price and reputation. Although not a true "R-comp" tire on paper, it performs like one by the account of every single test and review I've read (down to wear rates...). They seem like they're easily the most affordable (from a big brand) R-comp tire and combine that with a reputation for having tons of grip, it was an easy top contender. I had my concerns, though. For one, I'm told and have read that they are an autox tire, not really designed for high speed, pressure, and temps associated with open track. For another, the Mustang is a heavy car (as far as track cars are concerned) being roughly 3,800 lb. (including driver), which will amplify the unwanted open track load...

I never thought I'd ever run Michelin Pilot Sport Cup 2's on my 2012 Boss 302. The cost is astronomical and they are supposed to last the least of anything comparable. So how did I end up with (nearly) fresh Sport Cup 2's? A complete fluke. I came across a lightly used set with only a few hundred miles and no track time; 305/30/19 takeoffs from a GT Performance Pack Level 2 (GT PPL2). I knew my 71R's were getting very worn before the season started and likely wouldn't last the whole season, even this short one. The price was far better than a new set of RE-71R's, a little more than half, and local Time Attack rules (Canadian Automobile Sport Clubs) recently made 180 and 200 TW tires equivalent, meaning no PAX or PIP point penalty for going with 180 TW tire like the Pilot Sport Cup 2's. I have been very curious about how PSC2's compare to RE 71R's but I stayed away due to their being painfully expensive and, up to last year, their 180 TW rating would ...