Manual shift points

[kobachi]

I tend to keep my engine between 1500RPM and 3000RPM...but it's doubtful this is the "power band" of the engine. Anyone have thoughts on optimal shift points for a 5-speed?

[Bitsyncmaster]

Going 55 MPH on the highway you need maybe 15 HP. Sure you can run in 4 th. or third gear but it only buys you 10 MPG.

If you want to accelerate fast then you want to wind up the RPM higher.

[WelmoedJ]

I tend to keep my engine between 1500RPM and 3000RPM...but it's doubtful this is the "power band" of the engine. Anyone have thoughts on optimal shift points for a 5-speed?

I'm not sure I understand the reason for your question.
Are you going for fuel economy (as Bitsyncmaster seems to understand)?
Or do you seek the limits (most likely you do not, given the low RPM you mention)?
Or do you seek smoothness in shifting?

You can shift up very quickly in low RPM (over here called "new driving").
You also can hit high rounds before shifting (5000 RPM and over)
And probably each and every RPM in between.
It's all your choice.

[Delorean Industries]

The stock cams and exhaust have a limited power band. You can push it above 4200 but it is just spinning faster and not producing. The engine technically peaks at 5200ish in stock form but not on a stock fuel system. From 4200 on you are heading into lean territory.

[David T]

The stock cams and exhaust have a limited power band. You can push it above 4200 but it is just spinning faster and not producing. The engine technically peaks at 5200ish in stock form but not on a stock fuel system. From 4200 on you are heading into lean territory.

The gearing in the transmission was not optimized for the Delorean and there is very little you can do about it. Eventually you will develop a feel for the proper shift points and can even skip gears. You won't be looking at the tach, you will know by the feel and the sound of the car. Shifting for performance is different from economy. You won't need 5th under 40 MPH (and probably not under 50 either). Depends on the roads and the kind of driving. Don't over-rev and keep your foot off the clutch unless you need it to shift. You should not have to double-clutch and only slip 1st gear. If the clutch does not cleanly disengage get it fixed quickly before you muck up the parts in the transmission. Get the shift/MPH chart so if your speedo breaks you can estimate your speed form the tach (as long as you know what gear you are in!).

[DMC5180]

I've had a couple other Daily driver cars with manual transmissions. Those cars had shift lights on the dash which were intended to be aimed at best fuel economy driving. Both cars were at or near 2500 rpm. They were not gear specific but rather single point RPM based only. I tend to shift by seat of the pants feel plus sound and whether I'm feeling my oats at that moment.:biggrin: Normal casual driving I usually shift in the 2500-2700 range up through the gears. If I am feeling a bit more aggressive I'll run 1st gear to 5K or better and 2nd to 4K or better after that its a bit moot as I'm up to Highway speeds.

[kobachi]

I'm not sure I understand the reason for your question.
Are you going for fuel economy (as Bitsyncmaster seems to understand)?
Or do you seek the limits (most likely you do not, given the low RPM you mention)?
Or do you seek smoothness in shifting?


Not so much seeking the limits. I would like to shift in a way that gets the most life out of my transmission (only 16K miles on my car currently). The DeLorean manual talks about shifting in a way that doesn't "labour" the engine. The car generally feels/sounds good to me between 2000 and 3000 RPM, but I wanted to seek the experience of those who have owned the car for much longer and see if there was general advice. This is also my first stick-shift car.

So yes, I would like to optimize for smoothness, fuel economy, and life of transmission. Speed is not high on my list (I own two sport bikes to address that particular urge ;))

[Bitsyncmaster]

I think you will find where to shift when you get more driving time on the car. I never look at the tach when I shift. It's something I do automatically (I guess its feel, sound and speed).

[kobachi]

I think you will find where to shift when you get more driving time on the car. I never look at the tach when I shift. It's something I do automatically (I guess its feel, sound and speed).

This is how I do it too :) I've looked down to notice where the tach points are when I shift -- not watching the tach to decide when to do so. I just wanted to make sure I wasn't operating the engine too low.