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Old 10-31-2011, 10:32 PM
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Predator - MDS OFF Question

Just got the Predator installed tonight and chose the 87 tune plus MDS off option. Everything else is canned.

This question is for those of you with the VVT 5.7 and MDS disabled. Does it basically feel like and run about the same RPMs as it did stock with overdrive off? I'm running about 2k RPMs at 70.

Just wondering if anyone has any thoughts. It drives much better, definitely noticed a change.

Marcus
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Old 10-31-2011, 11:41 PM
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Re: Predator - MDS OFF Question

Not speaking from experience but it should turn about the same rpm. the converter is locked at that speed so even though the engine is working harder in MDS, the difference in rpm should be negligible.
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Old 11-01-2011, 12:51 AM
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Re: Predator - MDS OFF Question

Thank you for your reply Ryan. I'll set it back to stock tomorrow and take it for a preliminary run and then put it back on and check the difference.

If someone sees this in the meantime this is a bone stock 2010 WK Limited with the factory 18" wheels and tires. Can someone look at their RPMs on the way to work tomorrow and tell me what you see at 70 MPH?

Thanks!

Marcus
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Old 11-01-2011, 04:08 PM
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Re: Predator - MDS OFF Question

I don't have bone-stock, but I can get this for you in the next few hours.
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Old 11-01-2011, 04:43 PM
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Re: Predator - MDS OFF Question

Thanks man!

She's on her way home now so I'll get to play with it again shortly.

Marcus
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Old 11-02-2011, 08:39 AM
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Re: Predator - MDS OFF Question

Sorry, forgot to report back last night. I am running about 2K at 70 mph and this was with the "ECO" light on at the time.
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Old 11-02-2011, 09:00 PM
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Thanks man!

What's funny is the Eco light and Fuel Saver still comes up on the dash with it disabled. Ha ha!
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Old 11-02-2011, 09:48 PM
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Re: Predator - MDS OFF Question

Quote:
Originally Posted by MarcusRTJ View Post
Thanks man!

What's funny is the Eco light and Fuel Saver still comes up on the dash with it disabled. Ha ha!
Maybe it is based off of MAP?
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Old 12-24-2011, 01:27 PM
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Re: Predator - MDS OFF Question

Interesting comment about the MDS lights. I have a post under the "trouble shooting" forum about none of the lights coming on during 4 cyl mode on my 2009 GC Limited. The dealer told me my car doesnt have the feature of turning on the ECO light or the FUEL SAVER MODE when the MDS is active. Still find that unbelievable and have been wondering just what turns those lights on. Does anyone know for certainty, not speculation, what triggers the signal to turn the lights on? It would seem the most certain way would be a pressure sensor where they dump oil to the lifters, but that would cost $$ and I'll bet they aren't willing to do that.
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Old 12-24-2011, 07:06 PM
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Re: Predator - MDS OFF Question

With the MDS active, at least on the earlier (~05-08), the RPM with the MDS on is about 75-100 RPM higher than when not in MDS mode. In MDS mode the converter clutch is also not engaged.

On yours, Pops17, I still say somethings fishy. As far as the dealer putting the right oil in....not always true. When I bought mine from the Jeep dealer they were proud to announce that they had done me a "favor" and changed the oil for me before I picked it up. Only problem was they put 10W-30 in it, as indicated on the service slip. Since I own another Hemi vehicle with MDS, I know how it should work. On the WK it barely worked at all until I changed the oil. Just think of the $$$ they could make off some unsuspecting sole that comes in complaining about poor fuel economy, or the MDS doesn't appear to be working. I am still not sold on their "explanation" to you. Sorry, just my opinion. I've seen enough of the dealer BS on these forums to know that they're not all on the up and up, and in a lot of cases not very knowledgeable on the products they sell and service. Can't wait to see the final outcome on yours.
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