Top Cruising Speed

[Moneypenny]

Hello Forum...

Just looking for some opinions here. If you were presented with a beautifully smooth, perfectly graded and banked highway, with no other cars or law enforcement to worry about, what would be your highest comfortable cruising speed for sustained driving?

[sdg3205]

Hard to say. That has never happened. When that situation does temporarily - and very, very rarely present itself - I hit the gas. If it was the norm? Probably 120 kph/75mph. That's a nice cruising speed.

[Elvis]

160 kph is a great travelling speed, up to 180 it's ok, 200 is a bit unrelaxed

[Spittybug]

Really depends on car. With the Delorean, most will tell you that above say 75 they start to "float" a bit on the front end, giving a bit of an uneasy feeling. I think they are starting to airfoil and trying to lift off because of the flat bottom! When I still had my Infiniti G35S, that thing was a dream at any speed. On the long, wide, open parts of the Beltway in Houston in the middle of the night I could open it up for a few miles at a time. That car still had plenty of pedal even when doing 110+. Never felt loose at all.

[Michael]

That will depend on the drivetrain. Manuals will probably cruise a lot better around 85mph due to the taller final gear, where the 3 speed auto will want to cruise around 70mph. My auto on level ground spins around 3,100 RPM at 70mph where a manual will be much lower probably around 2,700 at the same speed. I personally have had mine at an (indicated) 120mph and no lie it was solid and stable. The suspension setup will not doubt have a lot to do with the higher speed characteristics as well. Remember stock D's are jacked up to the moon in the front...probably doesn't help when speeds get to triple digits.

I define "cruise" as a comfortable pace where you could drive it all day without stressing the engine, or make the interior noise unpleasant so Stage II and Stage I owners with the louder exhaust may feel more comfortable at the lower realms of the tach.

[Jonathan]

Really depends on car.

And the driver too.

A speed one guy might think is enjoyable might make another guy stressed out.

And depending on where you live and what the roads are like (not to mention what the laws are like too). In Ontario, we have a 50 over law that comes with a one week license suspension, one week minimum car impoundment, and up to a $10,000 fine. Not to mention what your insurance rates are going to be after that. Oh, don't forget that is 50 over in KILOMETERS PER HOUR. Which is closer to only 30 MPH. Most roads and rural highways here have 80 km/hr limits, and the major, divided highways are 100 km/hr limits. 50 over puts you at 130 km/hr and 150 km/hr respectively. That's only about 80 mph and 93 mph if you convert the units.

So, cruising speed? Probably closer to 60 mph day to day when just out for a drive. 75 mph when on the major highways. You can speed all you want here, you just don't want to get caught for one of the big numbers as it's now thrown into the "street racing" category. Not in the mood to see the DeLorean towed away from the side of the highway and going to court to deal with it, thanks.

Back to the car though...

Many cars might not be in ideal and perfectly maintained condition to make those higher speeds enjoyable. Flat spots on tires, various suspension components a little worn or weak, brake calipers sticking a little, door seals or panel fitment not great and making a lot of extra noise. Any of those can contribute to the cars not doing well at higher speeds. And the high front nose height they left the factory with as mentioned.

[mr_maxime]

I'm a bit more reckless, Id be in the 100+ mph assuming no speed limit or other cars.

[Moneypenny]

I really appreciate the input thus far. It's interesting to see the range of responses, and the attention to detail behind those responses.

I'll be getting 4115 in the next month or so, after a full go-over from DMC in Houston. It does have the Eibach suspension upgrade and a Stage II engine, and is a manual transmission car.

I'm thinking about some drives I'm likely to be making this summer. Parts of South Dakota, for example, have wide-open interstates with a posted limit of 80mph, and where traffic regularly travels at 90. If sustained speeds like that are uncomfortable or will cause undue strain on the car, then I want to plan my routes and/or trips differently. But if I can throw down 90mph for an entire tank of fuel with ease, that will be good to know.

Of course, I won't know how this car feels until I get it and drive it, but getting a sense from this community will help me manage my expectations. :-)

[81dmc]

With my car, the steering is remarkably annoying to control at high speeds.

[Moneypenny]

With my car, the steering is remarkably annoying to control at high speeds.

Do you have the Eibach kit, or is your suspension stock?