My information may be well out of date, but the Chrysler Orange box was a "street" style box with a fairly low RPM projected max, 5500 as I recall. If there are any other weaknesses in the system, the box may not be able to work up to its design level (5500 rpm). The MSD is intended for much higher RPM capability, also the higher spark strength & duration helps with any fuel issues so not surprising it works much better.
moparedtn, be careful with all cam specs, the reason folks went to quoting the .050 number is that manufacturers rated the duration at all kinds or tappet lifts that varied widely (.000, .005, .010, .020 etc), making specs impossible to compare. On top of that lift rates make so much difference in performance (and durability of valvetrain components).
Oh, I claim no expertise in them other than a working knowledge, trust me.
That's why when it became obvious that the purpleshaft I had was garbage and it was replacement time, I started a thread here seeking help and advice and once I was comfortable that I had learned all I was going to with that route, I got on the horn with Comp Cams and spent considerable time with their "experts" as well, picking their brains.
I had determined that it was going to be a Comp Cam in the car, thanks to many helpful posts from members here.
Once I had a short list of their cams that would be acceptable based on their recommendations, I then went "live" with a representative of Summit and he went about figuring out which ones were on their shelf for immediate shipment.
(I was under time constraints, trying to hit a time "window" between hospital procedures for my latest war with cancer, so I needed to MOVE if I was going to get it done).
I also verified with them (as I had with Comp) of what a stock 440 magnum cams' specs were so that I'd avoid an amateur mistake of getting something that wouldn't work well with the engine at hand, or at least try to.
Although the XE268 was #1 choice, Summit didn't have it in stock. Summit's folks recommended the Magnum 280 cam,
saying that they'd had a lot of positive feedback from their regular Mopar engine builder customers - but again, they had none on the shelf.
Next best option, given the time constraints? The Magnum 270 I have now.
Comps' guys told me it was "damn near an exact stock replacement", except for the dual duration part the stock one has.
Summits' guys concurred and called it a "one step up" cam.
I bought the cam and have been quite happy with the whole reassembly and break-in process.
It has a little rumble and I wish it had more, but I'm looking for simple and livable here, remember, so that's ok.
Sounds mean enough.
Anyways, back to the question at hand...
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Just picks up a signal from the distributor, sends a set amount of voltage to the coil and triggers the coil by grounding it. That is also why grounding the ECU is so important.
Very good, thanks.
So the differences between an off the shelf aftermarket replacement, the orange Mopar box and the chrome Mopar box is primarily just the RPM limit they'll work to?
