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Paul Kish

All I can do now to start back in is to say I’m sorry and didn’t mean to offend or criticize others input.

I think I learned a couple of new lessons on here.  They are only present your own thoughts and only address the questions and comments of the original poster, without any reference to anyone else’s post.  Any time you reference or use anything from anyone else you are running the risk of angering others and are hijacking the thread and taking it in a different direction.

I will again try to present my observation, without referencing any other poster.  I’m sorry for doing otherwise before.  And I’m sorry it does not accurately address the subject of “Slow in Slow out”, because until this thread I had no knowledge of it.


There can be something if needed and if the situation allows for it, between the end of entry deceleration and the beginning of exit acceleration or full acceleration.

Altering your entry line will alter your exit line.

Ideally you want to finish the straight at the highest possible speed, brake and enter a turn on a line which will put you on the best exit line. What you do in between is crucial to being able to exit on a specific line at the most advantageous speed.

Depending on what comes next after exit or during exit be it a racing situation, a straight very short or very long or another turn, you may or may not be at the maximum speed possible to obtain between entry and exit. But you still will want to be able to cover between entry and exit as quickly as possible and be on the best line at exit. The best line may be a line you need to complete a pass, it may be a defensive line or it may be simply the best line to obtain the highest speed until the next turn. What you do and can do between entry and exit is what will put you on the line you need, at the speed you want.

There is an actual line that can be taken on the track, that can be used between the end of entry and the start of exit, which is not a gradually changing line between where entry deceleration ends and exit acceleration is complete. It can be taken only if the driver deliberately inserts it between the end of deceleration and the beginning of acceleration.

The end of deceleration and the start of acceleration do not have to be an instant thing. A geometric ’arc’ can be inserted at the end of deceleration and before exit acceleration is started. The obvious way to insert the ’arc’ line is to slightly get on the gas and roll a little at entry speed. The ‘arc’ if planed for by the driver instead of going directly into acceleration, can allow for an even later ending of the entry straight and a change in exit line.

The rest of the point I’m making is the ’arc’ can be taken at a speed higher then entry speed. When deceleration ends, instantaneously grip is redistributed to the outside tires in a favorable way, where the driver can immediately accelerate. If the driver learns the skill to do it, it will allow for the ‘arc’ to be taken at a speed higher then their speed at the end of entry.

The potential net advantage is ending the straight later and with the slight increased acceleration through the ‘arc’ to it’s exit point, where full exit acceleration would begin. Because of the later entry and slightly elevated ‘arc’ speed time spent in the corner can be reduced. Because of the ‘arc’ nature of the line added between the end of the later entry and the beginning of exit acceleration, it’s possible to be on a line at exit you could not be on if you began your exit acceleration, immediately after deceleration. I’m trying to show the possibility of a corner line, which intentionally includes an ‘arc’.

Brake, Insert 'arc', Turn, Accelerate