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Discussion Starter · #1 ·
I've got a 2011 300c that I absolutely love but, I want more power. I'm not sure about an exact power figure but in her current form (93 octane diablosport tune) she's fun but isn't quite to the "scary" level that I was hoping for when buying my first v8 car. I was wondering what steps should I take next to get to the "scary" level when I nail it.
 

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Unless you want to spend a ton of $$$$ on this project, you won't be able to get to "scary". Scary would take a complete top to bottom forced induction, forged bottom end (with a stroker) and a little nitrous oxide added build. Then you'd have to rebuild the transmission to support the power level. You'd also have to a stronger limited slip differential and axles. To do it right, you'd probably be looking at $20K or more.

On the other hand, if you want to make it fun without breaking the bank, do a "well selected" cam (meaning not too radical), a good low restriction header back exhaust system, a lower ratio LSD differential, and either nitrous oxide injection or forced induction. Without going to a stronger rotating assembly, you'd be limited on how much of a nitrous shot or boost you could safely run. You'd also need to have a DS CMR tune done to get the full benefit out of all this.

You have a little more advantage over us guys that have modded the early Hemi's, as yours is a little more efficient from the get go. On my early Hemi's, with my mods. (see signature), I figure that I've picked up about 130-150 hp and gained a bit over 25% more in fuel economy. I've also retained the MDS on both of my 5.7's and have custom tuned the engines, MDS, and transmissions with my HP Tuner. To give you an idea, on our last trip with our 05 5.7 Magnum we went 361.4 miles and averaged 32.558 mpg. Outbound was 182 miles on 5.8 gallons of 87 non-ethanol (altitudes were about 2500-5300 ft.) or 31.379 mpg. Inbound was 179.4 miles on 5.3 gallons of Chevron 87 ethanol with Techron, or 33.849 mpg. Also, note that the MDS was active more than 90% of the time, both ways.
 
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Discussion Starter · #3 ·
On the other hand, if you want to make it fun without breaking the bank, do a "well selected" cam (meaning not too radical), a good low restriction header back exhaust system, a lower ratio LSD differential, and either nitrous oxide injection or forced induction. Without going to a stronger rotating assembly, you'd be limited on how much of a nitrous shot or boost you could safely run. You'd also need to have a DS CMR tune done to get the full benefit out of all this.
Do you have a recommended set up? I think I'm probably looking for around +100hp but I would like to maintain an exhaust setup that is as quiet as possible. I don't wanna wakeup the neighbors every time I do a cold start.
 

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Do you plan to do this all at once, or a little at a time like I did? No matter what you decide, I'd recommend you do things in a logical order. You already have the tuner, which is a good starting point. I'd address the exhaust system next. Headers and cat. back systems are a matter of choice, unless you live in a "smog nazi" state. If you're in a smog nazi area, you'll probably be limited to a CARB approved shorty header. If not, you can go with long tubes. On a 5.7 keep the primaries to 1 3/4 in. The larger diameter primaries will work fine, but you'll lose a slight bit of power. For the cat. back, I'd recommend you stick to the stock size tubing, use some sort of straight through mufflers and probably keep the resonators, unless you're going to delete the MDS. Just remember, the resonators are there to help remove any droning.

On my 5.7 Magnum, I run JBA shorty headers, stock tubing with a stock SRT8 "suitcase" muffler and stock SRT8 resonators. With this setup, In MDS mode at less than 2000 RPM, there is what I would describe as a muted bass tone....not really a drone. Above 2000 RPM is quiet but does have a fairly quiet rumble to it, especially at idle.

Next, I'd do the cam.....and lifters if you're going to do the MDS delete. IMO, cam selection is critical, as you do not want to go too radical otherwise you end up with reduced low end power and a terrible idle that you'll have a difficult time tuning it. You currently have VVT, but many of the aftermarket performance cams for the VVT engines are phaser limited or phaser locked and no longer a true VVT engine. This is not a problem. The cams in both of mine are MDS friendly and are one of the keys to the better fuel economy that I get with both of them. I also have both set up with a fixed amount of cam advance to help with the low end power. Maggie is advanced a total of 10 degrees (4 on the cam grind and 6 on the timing), and my Jeep with the same cam is advanced a total of 6 degrees (4 on the cam and 2 on the timing). I also use 6.1 timing chain tensioners on both.

The tuner, exhaust system and cam will probably net you around 75-90 hp....maybe a little more. IMO, you'll also want to do some "tweaking" to the transmission. If you can get yours hands on a "real" Mopar Performance Transmission Control Module, that would be the "cat's meow", and also a Transgo Shift Kit. Otherwise you'll have to use your DS tuner, a CMR tune for the DS unit, or pick up an HP Tuner and spend a few months trying to figure everything out to make it better. My engines and transmissions are both HP tuned, but I started with DS 93 tunes and modified them a bit at a time until I got the best performance and fuel economy. You'll find that, if you go overboard on any of the mods, you'll more than likely not be maximizing your performance or economy and may end up having driveability issues.

Beyond these mods. there are a few more things that will help to lesser degrees.....underdrive crank pulley, catch can, coils, cold air set up (modify the stock one), maybe an 85 mm throttle body, and stuff like that. If you want to get a little more ambitious, you could mill the heads a bit and clean up the ports and port match.....don't do a complete port/polish though unless you're going with forced/nitrous induction or a stroker kit..
 
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Discussion Starter · #5 ·
Do you plan to do this all at once, or a little at a time like I did?
I plan on doing a little at a time until I'm satisfied with the output. I do have MDS disabled, mostly because I've read horror stories of it eating cams if it fails, also because I'm not too terribly concerned with fuel economy. I'm also satisfied with the changes that DS made to the transmission, she's more than responsive enough for me to boogie when I need to. I've seen some youtube videos about using the 6.4 cam in the 5.7 and that sounds like the best bang for buck cam option. As far as exhaust I live in Texas so I've still got to be able to pass emissions and I don't want to get loud. I only want to free up the exhaust enough that it doesn't restrict the flow needed by the new cam.
 

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@magnuman : "...advanced a total of 10 degrees (4 on the cam grind and 6 on the timing) "

Don't mean to hijack the thread, but could you share some detail on the cam. Is the '4 on the cam' a ground in feature or did you dial that in when doing the install? Is the cam a stock Sidewinder or was it custom ground?

Your maggie is a model for what I hope my Blondie to become ;)
 

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I plan on doing a little at a time until I'm satisfied with the output. I do have MDS disabled, mostly because I've read horror stories of it eating cams if it fails, also because I'm not too terribly concerned with fuel economy. I'm also satisfied with the changes that DS made to the transmission, she's more than responsive enough for me to boogie when I need to. I've seen some youtube videos about using the 6.4 cam in the 5.7 and that sounds like the best bang for buck cam option. As far as exhaust I live in Texas so I've still got to be able to pass emissions and I don't want to get loud. I only want to free up the exhaust enough that it doesn't restrict the flow needed by the new cam.
Since you have the smog nazis, you'll probably have to stick with something like I did....JBA Shorty headers (CARB approve) and a good low restriction cat. back. The shorty headers won't be as efficient as the long tubes, so you won't get a ton of power from them, but the are better than the stock log manifolds.The factory cat. back isn't too bad, but the suitcase has switchbacks in it and isn't quite as efficient as it could be. For years I ran a Daytona Charger Suitcase and stock 5.7 resonators on mine. It was OK but I never really cared for the "raspy" sound of it. When I found an almost new stock 6.1 system that was sitting in a guys basement forever, I jumped on it. I love the way it is with this system.

If you're not going to retain MDS, you're open to almost any cam that you want. A lot of folks have used the 6.1 or 6.4 cams and have been happy. When I had to replace the cam on my 6.1, I opted for one that gave a better low end and sacrificed a little on the top end. It's not like I ran it at 4000-6000 RPM all the time (only about 75% of the time), so a little more low end power was more desirable. I am not familiar with the 6.4 cam timing but I am guessing it is similar to the 6.1's. Remember, a bigger displacement engine, especially one with higher compression, will offer more torque from the git go. That's why I say that cam selection should be critical for you and you should research all options, as there are a bunch to choose from. I opted for the Frank's Racing Sidewinders for two main reasons.....they were MDS friendly and they had been proven for years to be a good low end torquer cam. Personally, I'd look for something with a .520-.550 lift, a duration of about 250-275 and a Lobe Separation Angle of around 112-114....lower number will give better low end performance. Examples: The stock 6.1 cam had a LSA of 117 degrees and the stock 5.7 cam has an LSA of 113 degrees. Also, IMO, with any "descent" performance cam, you'll need, at least, 6.1/6.4 valve springs and push rods...at least this is true for the early 5.7's.
 
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@magnuman : "...advanced a total of 10 degrees (4 on the cam grind and 6 on the timing) "

Don't mean to hijack the thread, but could you share some detail on the cam. Is the '4 on the cam' a ground in feature or did you dial that in when doing the install? Is the cam a stock Sidewinder or was it custom ground?

Your maggie is a model for what I hope my Blondie to become ;)
According to the manufacturer, they had ground 4%'s of advance into the cam at the factory. At the time it was a stock grind. Additional advance was done at the cam gear with a cam timing advance kit......2 degree offset insert for the Jeep and a 6 degree offset insert for Maggie. I did it this way, as I did the Jeep first and wasn't sure if the advance and cam lift and duration would cause piston to valve issues. It wasn't, so I went 6 degrees on Maggie. Be aware that one tooth on the cam timing gear is a slight bit less than 7 degrees, so if you're going to advance, you could just do one tooth and not need an advance kit. Double check this though, as it's been a lot of years (at least 11) since I did the cams on both of mine. I also first rotated the engine by hand to make sure there was no piston to valve issues before I started them for the first time.
 
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