Passing an Opponent: Inside Line vs. Outside Line


Getting around an adversary relies on different rules depending on which line they’re passed on. Well, ideally, anyways. The inside line offers superior car placement, but comes at the price of reduced confidence and a greater chance for error. Attacking or defending on the outside is challenging in its own way; offering familiarity but minimizing the number of options in combat. These lines allow for different levels of aggression, but must always be done with a few accepted rules of racecraft that almost seem like etiquette. In reality, these “manners” have more to do with ensuring the racers don’t crash than it does with being polite – given the chance, most drivers would have no problem pushing a rival off-track.

Positioning on Corner Entry

When two drivers approach a corner side-by-side, their placement relative to one another is very important. The rule of thumb is that the car making a passing attempt needs to be at least halfway alongside the car in front before they turn into the corner to consider any sort of move. While this isn’t written in stone, it is a good way to ensure that the cars don’t touch and damage one another.

It also has to do with right of way. If the front wheels of the trailing car are not past the rear wheels of the leading car by the turn-in point, then the leading car is not expected to provide racing room into the next turn and is free to, and will likely, chop them off. The reason for this positioning is to ensure the leading driver is able to see their attacker through their peripheral vision, if not through their mirrors.

If the white Renault insists on turning in with the BMW, which has the lead and the right of way, it is forced to take a bit of curb to avoid a collision.

Of course, there’s some gray area here – and for this reason, a courtesy check in the mirrors is a good way to stay out of trouble. But as discussed in an article on the merits of kart racing, racing wheel-to-wheel eventually develops a sense of spacial awareness, so that once a driver is approaching alongside, their opponent usually knows they’re there. However, with a-pillars that obscure the driver’s view, blaring exhausts and halo supports on their racing seat, sometimes it’s hard to identify just where the enemy is. This is part of why wheel-to-wheel racing is so difficult.

Charging on the Inside Line

Even if the car on the inside is slightly behind by the apex, the corner is theirs since they offer the outside-liner nowhere to go.

Assuming the attacking car has pulled alongside by corner entry and is willing to fight for the corner, its driver must still be able to hold a decent line; understeering recklessly into their opponent is generally frowned upon. It’s fine if speed is scrubbed significantly at the apex, since this can still award the inside driver because of their position on-track, but the driver should usually be able to control their car and continue to run along the inside. Because they assume the inside line, they can dictate the pace, slow their opponent, and give them nowhere else to go. The corner is theirs if they’re able to squeeze ahead just barely, even if they lose speed in doing so.

If they’re faster out of the corner than their rival on the outside line, they are free to use the full width of the track as they see fit. The corner is theirs now, and their adversary should concede their position and expect them to move across.

In this instance, the leader, Number 1, was right to use the full width of the track. Number 5, being behind at the exit, was squeezed fairly and caused this accident.

In this instance, the leader, Number 1, was right to use the full width of the track. Number 5, being behind at the exit, was squeezed fairly and caused this accident.

However, if they’re slower than the car on the outside line, they must be willing to take a bit of inside curb to make it through the corner. In this situation, the car on the outside can dictate the pace and is free to be a little more aggressive and the car on the inside line should not be surprised if they get squeezed slightly.

Not simply being content with getting in front, some drivers dive wildly inside, making a mess of their overtaking attempt. Charging too quickly into the corner can allow for a rival to counter attack, since the door is open and while the attacker struggles to regain control over their car, the driver recently passed can take a cleaner, wider line and out-accelerate the attacker on the next straight. This move will be discussed more thoroughly later on.

Holding the Outside Line

Here, the same standards for overtaking apply, but being on the outside changes the perspective somewhat. If a driver on the outside is behind at the corner entry, they should back off slightly, since the driver on the inside has the right to move across and use the full width of the track on exit, and can block their progress if followed too closely. Sometimes a little gap can help get a decent run on an inside-line attacker out of a corner, but it’s a very challenging thing to do.

If the opponent is totally alongside at corner exit, the two drivers can exit the corner side-by-side, and each driver is urged to leave a bit of room and not veer in any direction. If the opponent isn’t completely alongside by the turn-in point, then the driver in front can cut across and use the entire width of the track. In the eyes of the marshals, most collisions caused here will be the fault of the following/attacking car.

In BTCC, where aggressive driving is the norm, even a few centimeters are left between two rivals exiting a corner side-by-side.

The reasons an around-the-outside pass can work, despite covering a longer distance, is largely psychological. Yes, the outside line offers more grip as the race wears on and rubber is deposited there, but the driver on the outside has familiarity with the braking point. The inside line is less certain; and the driver there will probably be a little more tentative to brake later. Additionally, if the driver on the inside makes a mistake and runs wide, it almost ensures a crash.

One crucial piece to remember about the outside line is that it is often very slippery just beside the apex, where all the marbles are collecting. While a rival challenging a position might motivate a defending driver to hold onto their position and go side-by-side, running on the outside here can be dangerous. It’s quite easy to carry the same speed into the corner as the man on the inside and run off the track. On street circuits, this kind of move can quickly put a driver in the wall, and must be done with extreme caution.

The Over-Under, or the Switchback

If an opponent is bold enough to try a move down the inside, a defending driver on a conventional line can block against this move by allowing the driver through momentarily. Because they’re approaching on the outside line, they can delay their counterattack just long enough to let the attacking car on the inside pass by, then take the textbook line through the corner. If they get their timing right, the attacking car will be busy gathering up the slide they’re likely dealing with, and the defending driver can take the proper line and pass them down the next straight with the added speed from the better cornering line.

The one situation where this doesn’t work is in a three-car sandwich. If the defending driver lets the attacker through, their reduced speed can sometimes spell an accident with a driver following closely behind the pair, who will try to move in on the inside when they sense an opening. In these sorts of situations, it pays to be ultra-cautious.

In short, there’s no generally-correct way to go about these sorts of interactions. Each situation requires consideration of the opponent’s driving behavior, the amount of grip available, and what follows the corner that’s being contested. In every situation, however, it pays to be alert and willing to concede a position when passed. After all, there are plenty of opportunities to re-pass if one drives with their head.

About the author

Tommy Parry

Tommy Parry has been racing and writing about racing cars for the past seven years. As an automotive enthusiast from a young age, he worked jobs revolving around cars throughout high school, and tried his hand on the race track on his 20th birthday. After winning his first outdoor kart race, Tommy began working as an apprentice mechanic to amateur racers in the Bay Area to sharpen his mechanical understanding. He has worked as a track day instructor and automotive writer since 2012, and continues to race karts, formula cars, sedans, and rally cars in the San Francisco region.
Read My Articles

The Art of Driving delivered to your inbox.

Build your own custom newsletter with the content you love from Turnology, directly to your inbox, absolutely FREE!

Free WordPress Themes

We will safeguard your e-mail and only send content you request.