Anyone know how to tell when she drops into 4 cyl mode? When I'm on the hiway, I'd like to know the highest speed possible and still have MSD kick in. Cant tell...65,70,75...???
Anyone know of a aftermarket gauge or indicator light?
Also..anyone know of a Magnum club in Nor. California?
Thanks

 

Check out the mds mod on this site , it covers installing a led somewhere on the dash and the light comes on when you are in the 4cylinder mode

 

I don't know what the highest the MDS will kick in at, but the main thing is as long as you're not accelerating or going up steep inclines it will kick in. I have done long road trips at 75-80 and gotten 26mpg, so I know the MDS is still working at those speeds. Best road trip mpg I've gotten so far is 28, and that seems to be as long as I don't do too much screwin' around. It's just so hard not to punch it and pass people on the road trips, so typically 24-26 is what I get on trips longer than 40 miles.
We're planning a trip south to California, and instead of taking my wife's V6 17mpg Nissan, we'll be taking my V-8 Hemi-powered monster (I said it was because of the mileage)...which is true- we'll save a lot on gas in my econo-RT on the trip compared to a consistent 17 mpg car. But we'll have fun while savin' on gas...Gotta like that!

 

It is suppose to operate from about 15-80 mph. There are many parameters that have to be met to get it to come on, i.e. oil pressure, speed, must be in "D", engine coolant temp., manifold pressure, etc., etc. You can do the mod. I developed and monitor its operation easily. You can also (if you desire) modify your driving habits to make it work more and longer. It can be coaxed to some extent, especially in town. On the highway, it is very predictable, especially above 50 mph. Here's the link on how to install the light:
http://www.lxforums.com/board/showthread.php?t=11575
If you have any questions, feel free to ask. Hope this helps.

 

I read the reviews of the Magnum from the 11/04 Road & Track, and they stated that no one on their staff could tell when the changeover happened. They gave the car nothing but rave reviews as well.

 

RTracer,
This is the best part, you can't tell when it kicks in... If you are in a driving 'condition' that you would notice the MDS kick in, that 'condition' won't allow it to activate. It will only go into MDS when 1/2 of the engine is not needed.

Now, I have read that if you have after market exhaust, that you can tell when MDS is activated, due to a drone or something, and they weren't too happy about it. (Drive all day in 4th and MDS will NEVER turn on)

The only situation that I have been in to know it is on is when I step on it while it is in MDS. Feels like a delay when the A/C is on and hit the gas. Once, going to Vegas with the A/C on, I punched it while both the MDS and A/C were on. Double delay, not more than a second or so... 25.5 MPG from this 5.7 Liter V-8... I love MDS!

 

Yes, they really did a good job with the MDS.

 

the top speed for the mds on my car is 83 mph.
the lowest is 38 mph.

 

I cant tell when it switches to 4, but there is a slight surge (very minor, but noticable) when the other 4 kick in. I dont know if keeping it in a lower gear deactivates it or not, some people say 3rd gear, some say 4th. Anyone really know ?

 

After a few thousand miles, you can pick up the change when it switches over from 4 to 8 cylinders. I mostly notice it when I am cruising at about 60, and tip into the throttle slightly. I can feel the slight surge that strippedhemi describes. I cannot feel it switch over from 8 to 4 cylinders at all.