[ches]

I've noticed something about my S, and perhaps the cognoscenti here can assist. Is it just me, or is downshifting for the purposes of engine braking just not all that effective with the S? I've never owned a supercharged (or turbocharged) car before, and it occurs to me that the compression ratio is much lower than on a normally-aspirated engine. Maybe that's it?

Anyway, what I'm finding is that the practice of downshifting makes for wonderful sound effects, and it might get you into the right gear for exiting the curve, but it doesn't seem to do much to slow you down.

I'm not complaining, really, just... noticing. This is where my mind wanders during my morning commute.

[zogbogbean]

I've noticed the same thing... I went from a 2k Mustang GT to the MCS and the difference in engine breaking betweent he two is huge.

I think one reason for this is the gear ratios being very close for the gears that one would downshift to in a typical engine break situation.

It's just the way the car is I guess... it doesn't bother me eiter, but like you, I've noticed it.

-gb

[RickB]

Brake parts are a lot cheaper than engine parts; I think I'll leave the braking to the brakes!

[erazo]

Not only have I noticed that the braking effect is minimal, but the pop-up in rpms seems higher, especially from 5th to 4th.

During the break-in period, I'll do most of my braking with the brakes.

[ches]

Quote:

Originally posted by RickB
Brake parts are a lot cheaper than engine parts; I think I'll leave the braking to the brakes!

Well, that's a separate issue. I guess I was hoping not to open this can of worms.

This was a topic of great discussion in Road & Track's Technical Correspondence column many years ago. (I'm fairly certain it was Road & Track, but time may have faded that detail.) Anyway, they talked to many automotive engineers with impressive titles, blah blah blah. The argument put forth was that engine braking is probably easier on your car than brake-braking. This assumes you properly blip the throttle to get the engine's flywheel speed equal to the transmission input shaft so there's no appreciable clutch wear on the upshift.

The compression of the engine coverts the car's forward motion into heat. A car's engine is much better equipped to dissipate heat efficiently than the braking system, and the amount of heat we're talking about it much less than what the engine endures in the course of normal operation.

At least, that's what I've believed all these years. My last car went about 80,000 miles between brake jobs and 210,000 miles on the original clutch, so I can't be mangling things too badly... although, now that I think about it I did have to get the valves done once. I can hear you all chortling now, but I have to believe this was an unrelated repair.

In all seriousness, I've never heard it said than engine braking is bad for the engine, but I'd be curious to read other perspectives on the matter.

[erazo]

Nowhere have I heard from reliable sources that engine braking is harmful in any way. Of course, you do need to watch rpm and blip the throttle to avoid clutch slewing, but I don't know of any instance of early engine or transmission replacement as a result of engine braking.

On the other hand, I have spent much more on brake service on my automatic transmission cars (Cherokees with towing packages) than on my manuals. I have never had to replace a clutch.

But I noted as you did that my MCS' engine exhibits little brake effect.

[BruceK]

Quote:

Originally posted by erazo
...Of course, you do need to watch rpm and blip the throttle to avoid clutch slewing ....

????

[Garfield]

In autocrossing (and on the road) I've found both the Cooper and Cooper S to be the easiest cars to put in 1st gear than anything I've ever raced. I can easily blip the throttle (to the matching engine speed) and put the Cooper S in 1st gear at about 35mph. It's not necessary often, but it helps greatly coming up on very sharp turns.

Because of this, I frequently engine brake the car all the way to the stoplight on the road.

I believe the reason it doesn't seem like it's doing much is like others have said, the ratios. Just downshift to the next gear down, you'll feel it then.

Brian