The Ultimate Handling Guide Part V: The One Unforgivable Sin, Overlowering Your Car

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The 2010 Formula D season has gotten a lot tougher with the cars getting much faster over the 2009 season.  We started helping Matt and suggested raising the car to get more usable wheel travel among other things.  Matt is killing it even more this year even with much tougher competition. Sorry superlow Matt fans, please continue to support Matt!  There is a reason why the cars that normally populate the Top 16 are not super low any more, it doesn't work.  “Car style is not what I want to be known for. I would like my car to look as cool as possible granted, but this is a competition, not a car show. When that is a critique someone levels against me I want to say I don't take them very seriously in their opinion of or understanding of professional drifting.”  -Matt Powers  Photo from Speedhunters.com

Lately the rise of the Hella Flush aesthetic is also to blame. The look of big lipped Wheels with stretched tires tucking into the wheel wells just missing the fenders brings another layer of stupid to the table.  The fact is, cars are designed to run at close to the stock ride height and making them super low messes stuff up on many levels.  Do you wanna be Hella Flush or Hella Functional?  If it’s the latter read on.

This is a comical example of two retarded trends, Hella Flush and Demon camber.  You should be able to figure out why this doesn't work!

FWD cars can be Hella Flush too where the offset works to increase torque steer and steering wheel fight.  Another thing we don't get about the trend is the bike racks without bikes.  Maybe your fixie goes here?

A Sentra SE-R is a typical example of a car that should not be lowered more than an inch.  It can be lowered more than that but its suspension design isn't happy about it. This situation is common on many cars and not just indicative of the SE-R’s design, we have just thoroughly studied this car's geometry because we race one.

Hyperco lowering springs for the Sentra SE-R were an exception, they were made only 1″ lower than stock and 100% stiffer.  These actually helped handling when combined with a good set of shocks.

The first problem with lowering the SE-R (and most McPherson strut equipped cars) is that it only has about 2” of jounce travel at stock ride height in the front suspension. Let's say you lower the car the typical 1.5”, you are left with only about .5” before you hit the bump stops. Your typical aftermarket lowering springs only up the spring rate a paltry 20% or so, not enough to keep the car off the bumpstops with only 0.50” of travel. Not only does this ride poorly, bottoming out frequently and all the time if carrying passengers, but in a corner, when the car leans over, the suspension will quickly settle on the bump stop causing the spring rate to rapidly ramp up approaching infinity quickly as the bump stop smushes down. This causes huge amounts of weight transfer and a build up of slip angle in the outside front tire suddenly resulting in relentless understeer.  When the car initially hits the bumpstop, the perceived increase in stiffness makes the car feel responsive, sort of like a go kart but this snappyness in steering response turns into inescapable understeer in a few milliseconds after turn in is initiated.

Mad Mike Whiddett is the most famous person representing the Hella Flush aesthetic in actual pro competition with the Bad Bull RX-8.  He is going to go more conventional for next years Formula D season to get his car to handle better.  Sorry Hella Flush fans, Hella Functional rules!

It gets worse, some cars like a Nissan B14 Sentra have very little rear wheel travel.  If the car is lowered too much, it can bottom out in the rear first, resulting in a lot of sudden oversteer.