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Discussion Starter #1 (Edited)
I am strongly considering getting a I-1000-DCX (for 2nd Gen 300), but have some questions.
For all questions, assume vehicle is bone stock other than tuner... I may do exhaust, unlikely to do CAI. I've been reading lots of posts on this, but most are either with lots of other mods, and/or first gen cars.

1) Noticed any real improvement in fuel economy? Diablosport indicate the 93oct tune improves efficiency and power, which makes sense, but is it something you actually notice (fuel economy wise)? This would help sell the Mrs. :fing02: as well as just be a nice thing to do..

2) Has anyone run on a dyno and have A to B results of stock tune vs Diablo tune with no other mods? Diablosport says 20lb-ft on a SRT, but what about the 5.7?

3) Diablosport indicates that most of the increased torque/power is at low RPM, which is what I'd like... more effortless torque for highway cruising. Anyone noticed a difference here?

If I can get a good benefit either more usable power and no detriment on fuel economy, or improved fuel economy + power, or better fuel economy I'd be inclined to do it. I'm also rather annoyed by Chrysler deciding that a 360+HP car should have a 118mph speed limit, not that I drive that fast, it just seems silly. I also am considering larger dia. tires to fill out the wheel wells a bit, improve ride quality and reduce the liklihood of bent rims, so I like being able to recalibrate for that.
 

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Discussion Starter #3
OOPS!! How'd I end up here? Can a MOD please move to the gas engine "Electronics For Performance" section (or other section if that's not best?)
 

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If fuel economy is your biggest concern then I would say that you should keep your stock tune. The benefits of using the tuner on a mostly stock vehicle come from a combination of a number of different tune feature. First, you do get a bump in HP and torque, maybe 10 or so, a little more with CAI and exhaust. Added to that are firmer shifts, higher shift points and increased throttle response, which all combine to increase acceleration. Then you have features that keep you from loosing power that you already have. Installing a 180 degree thermostat and adjusting the fan speeds will go a long way towards preventing heat soak and loss of power. I run the 91 octane tune on 93 gas. The 93 tune tends to be knock sensitive and pulls timing if the octane isn't all there. The 91 tune on 93 gas allows plenty of tolerance and doesn't pulls timing. All of these changes added together add up to a increase in power and performance that you can really feel. If you add to all of this with a custom tailored tune, for example Johan or a CRM custom dyno tune then you will be getting the most out of your engine without making any internal changes, such as cam and/or heads. But from my experience, if you are looking to save fuel these changes are not going to help because you are going to like the way your car feels and drives and you will not be able to keep your foot out of it. You may tell yourself that you can but trust me, you won't. Oh yea, and you can increase the speed limiter. You may tell yourself that you won't go faster that 118 but when that little BMW wants to test you on a quiet highway.........
 

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Discussion Starter #5 (Edited)
Thanks for the input, I certainly see what you're saying, but I possibly have a bit of a unique situation. Most of my driving is commuting to work, which is 33 miles one way, and more than 70% of that is straight, flat, 4 lane highway with the cruise control and eco light on. The main thing I'd like is to get some more available torque at the low RPM range to avoid downshifts on the occasional hill etc.

Also somewhat counter-intuitively it seems like I tend to drive more slowly in a more powerful car... when I was driving my wife's civic as a daily driver, or our Mazda CX-9 I spend a lot more time with my foot to the floor trying to get it to get out of its own way. With the 300 I'm much more relaxed, I think because I know the power is there when I need it I don't feel the need to floor it all the time like I do in the slower cars. But also like I said 70% of my driving is cruise control at 65mph. Oh I still have my fun with the car, but usually pretty easy on it. I was floored that I averaged 30mpg on my last 200 mile trip!

Also, I thought the Diablo had an 87 octane "econo" tune? or was that an older version?

I don't care so much about peak HP/TQ, but would like to have some more torque below 4krpm... seems like that's where the engine really starts to sing. Would like to get more of the Bentley torque curve... 4500rpm redline, and unlimited torque (well, 616lb-ft, but plenty enough to get 5,600lb going at an alarming rate). Of course that's with 6.75L and twin turbos... but then the 300 is what, 1,600lb lighter?



If fuel economy is your biggest concern then I would say that you should keep your stock tune. The benefits of using the tuner on a mostly stock vehicle come from a combination of a number of different tune feature. First, you do get a bump in HP and torque, maybe 10 or so, a little more with CAI and exhaust. Added to that are firmer shifts, higher shift points and increased throttle response, which all combine to increase acceleration. Then you have features that keep you from loosing power that you already have. Installing a 180 degree thermostat and adjusting the fan speeds will go a long way towards preventing heat soak and loss of power. I run the 91 octane tune on 93 gas. The 93 tune tends to be knock sensitive and pulls timing if the octane isn't all there. The 91 tune on 93 gas allows plenty of tolerance and doesn't pulls timing. All of these changes added together add up to a increase in power and performance that you can really feel. If you add to all of this with a custom tailored tune, for example Johan or a CRM custom dyno tune then you will be getting the most out of your engine without making any internal changes, such as cam and/or heads. But from my experience, if you are looking to save fuel these changes are not going to help because you are going to like the way your car feels and drives and you will not be able to keep your foot out of it. You may tell yourself that you can but trust me, you won't. Oh yea, and you can increase the speed limiter. You may tell yourself that you won't go faster that 118 but when that little BMW wants to test you on a quiet highway.........
 

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There is no ecno tune anymore on the new tuners. I think that's because Chrysler has already ecno-ed out the stock tune, with MS and all. I don't think that the amount of torque you pick up will make that much of a different in cruise control. I did have a guy at a car show tell me that his mileage went up on MLS after he did a Cam, but ha was looking at a 30 hp/tq jump. You might get a little.

2012 300S 5.7 V8
 

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Your mpg results may be limited unless you add the air component to the fuel & timing part of the equation. more air (in and out) + more fuel + better timing = better efficiency.

You will find that your hp & torque curve improves, moving down a bit in the RPM range and it sustains longer across the RPM range with a programmer.

Dyno results vary so much due to ambient conditions, fuel quality, state of tune and other variables that a reliable improvement measurement is normally a conservative measure. As with most any engine modification, and make no mistake this is a modification, Your Mileage May Vary.

I got positive results from my canned tune and subsequent custom tune. I hope you do to but don't kill the potential by not considering both ends of the air/fuel/timing equation. Remove one of those items and your three legged stool will collapse on you.
 

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Discussion Starter #9
My understanding from reviewing dyno results at LX forums is in general the CAI at best only gives some marginal gains at WOT, and I think the results I reviewed all had a DROP in torque. I'm really looking for more torque in the 2k-3500 range, rather than peak HP so I don't see that a CAI is going to help in that range. Not that I'm saying I'd never do a CAI but it would probably be farther down on the list.

Exhaust on the other hand some of the good designs can introduce some scavenging effects, which could give some benefits.

Your mpg results may be limited unless you add the air component to the fuel & timing part of the equation. more air (in and out) + more fuel + better timing = better efficiency.

You will find that your hp & torque curve improves, moving down a bit in the RPM range and it sustains longer across the RPM range with a programmer.

Dyno results vary so much due to ambient conditions, fuel quality, state of tune and other variables that a reliable improvement measurement is normally a conservative measure. As with most any engine modification, and make no mistake this is a modification, Your Mileage May Vary.

I got positive results from my canned tune and subsequent custom tune. I hope you do to but don't kill the potential by not considering both ends of the air/fuel/timing equation. Remove one of those items and your three legged stool will collapse on you.
 

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There is a mpg booster tune fyi. Just got my intune less then a month ago.
Do you have a V6 or a V8? The Diablo Predator had a "Economy" tune for my 2008 300 V6 but I did not see one listed on my Trinity for the V8. Just the ability to modify the stock 89 tune (MDS, shift firmness, ect.), and the 91 octane and 93 octane tunes. I Unless I missed something, there is no "Economy" tune for the 5.7L V8. They claim that their tunes will improve MPGs, and no doubt that is true if you drive the car conservatively, but there is no "Economy" tune as there was on the older Predator tuner.

I checked Diablo's site for the available tunes and they only list Modified Stock, 91 Octane and 93 Octane for both the V6 and V8. No "Economy" tune listed.
 

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I am strongly considering getting a I-1000-DCX (for 2nd Gen 300), but have some questions.
For all questions, assume vehicle is bone stock other than tuner... I may do exhaust, unlikely to do CAI. I've been reading lots of posts on this, but most are either with lots of other mods, and/or first gen cars.

...

If I can get a good benefit either more usable power and no detriment on fuel economy, or improved fuel economy + power, or better fuel economy I'd be inclined to do it. I'm also rather annoyed by Chrysler deciding that a 360+HP car should have a 118mph speed limit, not that I drive that fast, it just seems silly. I also am considering larger dia. tires to fill out the wheel wells a bit, improve ride quality and reduce the liklihood of bent rims, so I like being able to recalibrate for that.
My mods are:
1. AFE Stage 2 Intake
2. 1000-DCX Intune running canned 91 Octane tune
3. 255/45/R20s all around
4. Exhaust valves locked open

1) Noticed any real improvement in fuel economy? Diablosport indicate the 93oct tune improves efficiency and power, which makes sense, but is it something you actually notice (fuel economy wise)? This would help sell the Mrs. :fing02: as well as just be a nice thing to do..
I locked open the exhaust valves a few weeks ago, and after seeing an MPG drop in city driving (highway was unaffected), I pulled the trigger on the new mods above. My city MPG has returned to previous stock levels, even though I am driving around with a significantly heavier foot to hear that intake roar. I'm doing some highway cruising this weekend, and actually plan to experiment with stock tune + CAI vs canned 91 + CAI.


2) Has anyone run on a dyno and have A to B results of stock tune vs Diablo tune with no other mods? Diablosport says 20lb-ft on a SRT, but what about the 5.7?
Not yet.

3) Diablosport indicates that most of the increased torque/power is at low RPM, which is what I'd like... more effortless torque for highway cruising. Anyone noticed a difference here?
Sweet jebus - the mid-range pickup with the CAI+Intune is INSANE. There's not real butt-dyno difference with off-the-line acceleration, but when you put your foot in it at any speed, the grin spreads pretty damned quick.

I also chirp the tires on WOT in 2nd and third now using the paddles in sport mode.
 

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Discussion Starter #12
What do you mean by locking the exhaust valves open?
 

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What do you mean by locking the exhaust valves open?
It's not a feature you'll find on your car so it is a non-issue for you.

In addition to being a part of a system, which provides efficiency and optimum performance because the benefits of that system (intake, exhaust and programmer) are greater than the contribution they make individually, the CAI greatly improves throttle response.

While this is not a measurable HP/torque improvement, the car responds much quicker to throttle inputs. It's like it shed 500 pounds off the line.
 

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Discussion Starter #14
Ah, I missed that his was an SRT... makes more sense now.
 

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Update:

For reference, my previous bests stock were 9.2L/100km (25.5MPG) highway, 15.1l/100km (15.5MPG) city.

After opening the exhaust flaps (resulting in less backpressure at idle and lower RPMs) but leaving the rest of the car stock, my best was 9.3L/100km (25.2MPG) highway, 17.9l/100km (13.1MPG) city. I averaged much less city than before - usually the live display was somewhere between 18 and 20 (!).

After AFE CAI + Diablo 91 Octane Tune, my highway economy hit a best of 9.1L/100km (25.8MPG) and city driving (with a heavy foot enjoying the throttle boost+sound of that CAI) is at 16.0l/100km (14.7MPG).

So, I'm not quite back at city levels from before, but admittedly I am driving much more aggressively on the throttle so I can hear the glorious intake.

Additional details:
- tire pressures @ 33.5psi all around cold
- running 255/45/R20s
- just performed an oil change a few weeks ago too
 

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I finally pulled out my I1000 and changed my tune from 91 CAI can tune to the mpg boost tune and OMG huge difference in performance. Feels sluggish, dont get me wrong. It still is quick just feels like stock. The 91 CAI tune wakens up the car considerably.
Mods:
Mopar CAI
Flowmaster american thunder series catback exhaust
180 jet thermostat
Billet technology catch can
I1000 Diablo 91 CAI Octane tune
235/50/18 Dunlop sport tires
Hopefully Cam this summer
 

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I would appreciate any help with the following:My 2014 300C AWD 3.6L has horrible "city mileage" most time in the 15-15.5 range.Is there ANY aftermarket mod i.e ,CAI,Diablo tuner,losing weight,that would materially increase MPG?
 
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