Mysteries Abound

My brother and I have had a long-running conversation about projected and actual performance at Pineview Run. He contends that FWD cars have a major disadvantage compared to RWD because their lap times have been generally poor. Over the last year or so, several thoughts have come up.

• FWD cars don’t accelerate as well? Pineview has a prominent downhill section followed by an uphill. If the weight goes to the rear in the uphill, the FWD vehicles may not be able to get their power down effectively as they climb up the esses. This has largely been debunked by data: FWD cars accelerate very well.
• FWD cars are slower through the downhill? FWD cars put ~65% of their weight on the front wheels. When they are going downhill, the weight is even more biased towards the front. Having such an unequal weight distribution might make them difficult to handle.
• People don’t know how to drive FWD cars? To my chagrin, that was debunked by Mario driving a Veloster faster than me.
• FWD cars can’t turn? After looking at some data, I remarked that “of course FWD cars accelerate well, they are being over-slowed”. Mario’s position on this was, “you can’t go in faster because they aren’t turning”. I’m not sure this is true of all cars, but certainly a Civic was washing out on me.
• Best Motoring! None of this made much sense to me. If you watch Best Motoring, FWD cars are often more nimble than RWD on twisty tracks, like the Ebisu circuits in Japan.
• Assetto Corsa! In my own virtual testing in Assetto Corsa (yes, Pineview Run is in AC), I found that the Abarth 500 was actually quite good at Pineview, and suffered nothing from being FWD.

I recently had the opportunity to drive Mario’s wife’s Honda Civic at Pineview, and despite a decent power:weight ratio, it was disappointingly slow. Not only that, it didn’t feel like it had much grip. It completely washed out in some corners where Miatas were sticking like glue. Ultimately, I did agree with Mario about the Honda: it’s not as fast as it should be. However, I was still not willing to say it was a FWD disadvantage.

Then I drove the Civic at Lime Rock Park, and found it had some similar behaviors as before (disappointingly slow, low grip, brakes overheating). However, it was really fast on the straights (114). YSAR reader Sean made a very astute observation: Lime Rock doesn’t have many braking zones. True! I was hardly braking at all, and my brakes were smoking when I came in. Not just the fronts either, the rears were hot. Then Mario when out and coasted around the track in heavy traffic and when he came in the rear brakes were hotter than the front!

Solved?

Mario pulled up the AiM Solo data from the Civic and compared it to a Spec Miata that was also at Lime Rock. The SM was shod with Falken Azenis RT615K while the Civic was on Nexen N-FERA SUR4G. These should be roughly equivalent in grip, but if you look at the lateral Gs, the Civic was way down. Is it the case that I can’t drive for shit? Well, I hope not, and I think not. From my perspective, the car was sliding out mid-corner, unable to hold its line. We think this is because of Honda’s VSA (vehicle stability assist) applying brakes constantly. If the brakes are being actuated mid-corner, it’s going to take away from the lateral grip. Turning VSA off is a ludicrously complex procedure, so Mario never turns it off. But clearly we need to try that next.

At this point, we are cautiously accepting that the Civic is slow because of VSA, but it doesn’t explain why other FWD cars appear to be slow. Pineview Run has seen laps turned by some high performance FWD cars like a Focus RS, Fiesta ST, and Veloster N. On a bigger track, like NYST, these cars will eat Mario’s Miata for lunch. But at Pineview, the Miata holds its own. I still don’t believe that FWD is the major determinant here. There is overall weight to consider. Also, most of the FWD cars have turbos, and my experience with the Civic, which is turbocharged, is that the turbo rarely gets a chance to shine because there are no long straights. The current FWD lap record is held by a CRX, which is both lightweight and naturally aspirated.

I guess we’ll have to do some more testing. Maybe even in my car (wait a sec, do I have a car in New York now….?)