Bought 5.7 hemi/nag1 out of a cop car. Some questions.

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dustyaman

dustyaman

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First off Happy fourth of July everyone!
So long story short I sold my 360 and 727 and bought a 5.7 hemi/nag 1 setup out of a cop car that had 74,000 miles on it. Got a great deal for it that I couldn't pass up. I've already bought most of the swap parts for my 74 duster for it. My question is instead of having to spend 1500 dollars for a new cam for it to get rid of the MDS, can I just buy a tuner like a Diablo and just turn off the MDS? Or is that not possible. I know sublime technologies sells the wiring harness that comes with a ob2 port. So I'm just trying to figure out if that can work. Here is a picture of my car and the hemi.

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I attended a webinar a while back on this subject. I believe it covered the MDS and what your options are. I don't remember the answer, too many beers ago. But here's a link to the recorded version if you're interested, I'm not sure if it will let just anyone use it, but I thought it might be worth a try. GoTo Webinar
I Tried to use it on Microsoft edge and it didn't work, then I switched to Google Chrome and it worked.
Also keep in mind this webinar I believe is hosted by summit, so they're opinions could have some bias, I'm not sure.
 
A cam doesn’t have to cost $1500. I bought a 6.4 cam for my 5.7 for a little over $200, and the springs were like $150. Don’t have the numbers in front of me, just going off memory. Lifters will be $600+ if you buy factory one though, so I guess it does add up. I haven’t bought lifters yet.

Either way, almost certain you can turn MDS off electronically. The cars with Sport Mode did it from the factory when Sport Mode was on. But I can’t tell you which tuner module to buy to do it.
 
I will try the tuner route first and see if that will work. Thank you
 
Will FORScan work on Mopars? I learned to use it working on my Ecoboost Mustang in the last month, I haven't tried it on anything else. If it does, it's easy to disabled the factory "as built" settings with a laptop. I'll look for a buddy with a modern Mopar and research it.
 
Pretty sure FORScan is Ford only. But AlfaOBD is a similar program and works well on late model Mopars. But I doubt it can turn off MDS, I think that is a PCM deal only and AlfaOBD is more about body module settings like to turn on Performance Pages.
 
dustyaman said:
First off Happy fourth of July everyone!
So long story short I sold my 360 and 727 and bought a 5.7 hemi/nag 1 setup out of a cop car that had 74,000 miles on it. Got a great deal for it that I couldn't pass up. I've already bought most of the swap parts for my 74 duster for it. My question is instead of having to spend 1500 dollars for a new cam for it to get rid of the MDS, can I just buy a tuner like a Diablo and just turn off the MDS? Or is that not possible. I know sublime technologies sells the wiring harness that comes with a ob2 port. So I'm just trying to figure out if that can work. Here is a picture of my car and the hemi.

View attachment 1716271508

View attachment 1716271509
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If you plan to buy a harness from Sublime (Great company btw) you're more than likely buy going to buy an ecm from them as well.. not sure if you're looking at the quick harness or complete.. either way, you'll need an ecm. The ecm will run you 400 bucks and if you have a core, take $100 off. Anyway, have Blake set up your ecm any way you like. You can have him set your fan on/off settings however you like, turn off mds etc. He'll just do it.

If you want to change to a non mds cam/lifter.. look for a pull out 6.4 non mds. I bought my cam and lifters for Hoopty, for a few hundy with 30k miles. Looked near new, no issues. The 6.4 cam is a nice "no tune" cam but you will need to upgrade valve springs and you may as well have the heads freshened up if you're going that far. You can get Mopar Performance springs for under $100.. but factor everything in. Someone to do the heads, cam/lifters, gasket kits etc. You don't HAVE to do all that and can just have it turned off by Blake.

This is the springs you would need for a 6.4 cam
Spring 68277306AA | OEM Parts Online
 
dustyaman said:
First off Happy fourth of July everyone!
So long story short I sold my 360 and 727 and bought a 5.7 hemi/nag 1 setup out of a cop car that had 74,000 miles on it. Got a great deal for it that I couldn't pass up. I've already bought most of the swap parts for my 74 duster for it. My question is instead of having to spend 1500 dollars for a new cam for it to get rid of the MDS, can I just buy a tuner like a Diablo and just turn off the MDS? Or is that not possible. I know sublime technologies sells the wiring harness that comes with a ob2 port. So I'm just trying to figure out if that can work. Here is a picture of my car and the hemi.

View attachment 1716271508

View attachment 1716271509
Click to expand...
What year engine? Keep in mind the pre/post 2009 is year break for vvt or non. I know I have a takeout hellcat cam, and 6.4 valve springs on the shelf. PM me if interested. Literally brand new takeoff parts.
 
Dantra said:
No.. but sublime is a Sound German dealer, which does and Sublime components play nice with Sound German components.
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Cool I didn't realize that Blake was a dealer for Sound German. Chris at Hotwire is as well. All great guys to work with.
 
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Johnny Mac said:
What year engine? Keep in mind the pre/post 2009 is year break for vvt or non. I know I have a takeout hellcat cam, and 6.4 valve springs on the shelf. PM me if interested. Literally brand new takeoff parts.
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Sticks in my head that 6.4 valve springs won't work on 5.7 heads. I know for the 6.4 cam swap I will do on my 5.7 I had to buy 16 of the 68277306AA valve springs.

Can't say for sure if it is an issue with the Eagle heads, or if all 5.7 heads, nor if the 6.1 has the same problem. And not sure if it is length of the valve, or the valve spring pocket that makes it a problem. Only that I read that a 6.4 cam swap on a 5.7 can't use stock 6.4 valve springs.
 
DionR said:
Sticks in my head that 6.4 valve springs won't work on 5.7 heads. I know for the 6.4 cam swap I will do on my 5.7 I had to buy 16 of the 68277306AA valve springs.

Can't say for sure if it is an issue with the Eagle heads, or if all 5.7 heads, nor if the 6.1 has the same problem. And not sure if it is length of the valve, or the valve spring pocket that makes it a problem. Only that I read that a 6.4 cam swap on a 5.7 can't use stock 6.4 valve springs.
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I have personally used stock 6.4 valve springs on a 2010+, 5.7 eagle head, but I do not know all the nuances, if there are any. And the set on my shelf are actually 6.2 hellcat springs. Came out of the same hellcat as the cam I have. Sorry, not sure why I recalled them being 6.4. Good luck either way.
 
Johnny Mac said:
I have personally used stock 6.4 valve springs on a 2010+, 5.7 eagle head, but I do not know all the nuances, if there are any. And the set on my shelf are actually 6.2 hellcat springs. Came out of the same hellcat as the cam I have. Sorry, not sure why I recalled them being 6.4. Good luck either way.
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Nice! I prefer personal experience and I don't have any, so I'm just regurgitating what I read years ago. The 6.4 cam swap "recipe" says the 6.4 springs don't work. Sounds like maybe they do though.
 
DionR said:
Nice! I prefer personal experience and I don't have any, so I'm just regurgitating what I read years ago. The 6.4 cam swap "recipe" says the 6.4 springs don't work. Sounds like maybe they do though.
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Ya it's been a while, but I threw a comp cam in an otherwise stock eagle with just stock, Chrysler dealer 6.4 springs and made around 480 if I recall. I locked the timing and ran it with a holley hp.
 
Johnny Mac said:
Ya it's been a while, but I threw a comp cam in an otherwise stock eagle with just stock, Chrysler dealer 6.4 springs and made around 480 if I recall. I locked the timing and ran it with a holley hp.
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Nice! That's 6.4 numbers.

I would be happy if my 5.7 with a 6.4 cam makes 425 hp. :)
 
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