One working definition for "bogging" the engine would be that if you press down on the gas, the car doesn't accelerate. The classic "bog" is when someone doesn't downshift on a steep hill, and as they press on the gas pedal more, the car continues to slow down. This one is very bad for the engine.

If you can press on the gas pedal a little bit and the car accelerates, you're probably not doing any harm. You aren't getting maximum performance, but you're probably not doing any harm.

If you're pressing the gas pedal down further and the car is slowing, you're risking damage.

 

I don't think they are contradicting each other... I have a habit of not wanting to downshift to a gear that is too low and cause the RPMs to spin up too fast.

When I'm rolling under 5 mph, I'll put it into first. If I'm rolling under 12 I put it into 2nd. Around 18 and I put it into 3rd. This is only if I'm coming out of a roll. If I'm accelerating from a stop I change gears a bit later. However, when I was test driving the CRX, it was making that awful grinding noise, so I was wondering if I was in danger of doing that to my S (even though I only downshift to 1st if I'm less than 5 mph).

However, to use my previous example, if I come out of a roll at 18 mph and shift into 3rd gear, I don't stomp the gas. Rather, I just kind of touch it lightly to get the car going again. I know that if I put the pedal to the metal I will flood the engine, and I definitely don't want to do that. My only fear is that I might wear something else out with this habit of mine...

 

All S2000's have HID's, not just certain MY's.

 

You've received some good info here. I just want to put a different twist on it.
1st gear has a "blocker ring" (this is that slide bolt thing that Austblue mentioned) that prevents easy downshifts from too high a gear as it is easy to over-rev due to the ratio of 1st gears in general. Also it makes for very jerky downshifts if it is too easy to do.
As said, it can be done but you must not only rev-match but also double clutch. You need to release the clutch in neutral before the rev so that you can spin up the tranny. Only in this way, can the blocker ring be defeated. You will also find that as the car ages, you will be able to downshift into 1st at higher and higher speeds without rev matching and double clutching simply because things are getting worn more.

This "bogging" that is being talked about should be called "lugging" the motor. Bogging is more associated with heated intake air, starting off from a standstill type of scenarios. As described lugging the engine is where you make the engine try to accelerate the car at an rpm where there is barely enough torque to do the job. This is one of the worst things you can do to an engine. You will not save any fuel this way as the ECU is trying to dump lots of fuel into the engine to make it do more work. Unfortunately, under "lugging" conditions, the engine cannot use this fuel because it has too hard a time to increase revs (ie. wrong gear at too low a road speed.).

 

[QUOTE]Originally posted by xviper
[B]You've received some good info here.

 

I really don't mean to flame you for asking these questions but why would someone spend $32k for a car and then worry about $2/gal for gas?

I understand that no one likes to spend anymore for gas than is necessary but getting good mileage is the absolute last thing I would ever think about when driving a car that rocks like this one when it's in VETC.

Most people would be wondering how fast one can go in 3rd, which is almost 90 mph as I recall, rather than worrying about how slow. I figure I'm getting my best mileage in 5th & 6th cause there's no where around here I can hit VETC 'safely' in those gears.

To answer your questions about how slow and what gear it all depends on the terrain - it will be different if it's flat, uphill, or downhill - in other words it all depends on what the demands are on the engine. If you are going down a grade you can put it in 6th gear at 5 mph but if the grade is up you would want to be in 1st gear to get the optimum performance.

 

I have been told lugging the engine caused major havoc on the synchros.

Anyone agree or disagree?

 

[QUOTE]Originally posted by Asura
[B]I have been told lugging the engine caused major havoc on the synchros.

 

To expound on the gear and gas mileage, does anyone here know if downshifting to use the engine as a braking method degrades the gas mileage?

 

If you do it the "proper" way be rev matching, then yes, your fuel expenditure should be marginally higher. Would it be noticeable or calculatable? Don't know.