[RyzRT]

RY, I did not realize the 6-speed manual RT came standard with posi and the 8-speed auto did not.
How coincidental as I have been looking at a nice used 2016 6-speed.
Another plus for me if I end up getting it.

Jim........

Jim, you'll have the limited slip differential right off the bat with that 2016 6 Speed manual, of course you can always add the LSD differential to any automatic, but unless you can do the installation yourself it does get labor expensive. In 2015 the open differential was a 3.07 ratio and the limited slip equivalent is the 3.09, with the 3.09 being a swap out not requiring any other changes at all. Some of the best online suggestions for more off the line capability are the 3.70 ratio, but that change is also suggesting a torque converter change as well for the maximum combined gains from that ratio, along with a tune change.

Most all of us have to decide where are we going to stop putting money into these Challengers as some of these upgrades do force more upgrades to get the most benefit out of them. I just watched a YouTube video of an owner of a 392 Scat Pack removing upgrades he had done, so he could sell the car because he had just bought a Hellcat. Ry

 

[RyzRT]

Upgrades to the 5.7L HEMI that do add horsepower and rear end torque, that actually push the power to ground up to close to the Scat Packs capability, do have a major plus benefit to the owner. You have a good increase in power but you are still in a lower insurance bracket with the R/T 5.7, and you're getting better gas mileage as well.

 

[Mopar_NoCar]

Deleted

 

[RyzRT]

No matter your horsepower level, if you cannot get that power to the road you're just spinning while lower powered vehicles are flat walking away from you off the line. B Mason said it best when he suggested starting your 5.7 upgrades from the rear forward to get the power to the ground, then worry about increasing the engines output. As for myself I did the opposite and then proved the hard way what he said was exactly right. Because once my power level got me melting the rear tires, or should I say tire, I was not going anywhere fast off the line, it was an impressive tire spinning show, but that was all it was.

When I first saw Challenger advertisements burning down the tires I first thought that was so cool, until I was given a ride in a Hellcat Redeye and realized if he hammered it, he wasn't going forward fast off the line with his 797HP. So HP to weight ratio and forward momentum has quite a few factors involved to actually get the vehicle off the line. Most of the 5.7L automatic transmissions are fitted with open or conventional differentials using computer assisted traction control giving the owner the illusion of both tires producing traction.

That computer controlled traction uses your ABS braking system to apply brakes to the spinning rear wheel in an attempt to shift traction to both wheels.

Isn't that wonderful!

So many times I've longed for the best off the line I could possibly get and all I really needed was to apply the rear brakes? NOT!

Who honestly even thinks to achieve forward momentum and get off the line requires applying any braking what so ever to the rear wheels that are pushing you forward?

However the electronic traction control works OK, until you start increasing engine performance and you hammer it to do an off the line burn out and leave one line of rubber on the road, usually the passenger side rear wheel, how embarrassing is that coming from a Dodge Challenger!

Unless you've experienced that yourself you think I don't know what I am talking about, but those of you that have swapped to a Limited Slip Differential now know the difference real traction is.

Which brings up the next problem with traction the 245 width tires, that is really an entire subject all its own as rim width determines the width tire you can safely run on the rear. Tire width has to be matched to the rim width for the tire to sit flat to the road for the best overall traction. Which usually requires going to wider rims to run wider tires.

 

[bigallis1]

Well said Ryan..............

 

[RyzRT]

Now here is a really good thing about increasing your power of an R/T 5.7L HEMI, starting at 2015 you have the same 8HP70 transmission and 8 bolt driveshaft that the 392 Scat Pack has. So you can increase horsepower to around 485HP with no worries at all regarding the transmission and driveshaft HP handling capability.

Seeing as how the 392 Scat Pack is rated at 485 HP and 475 Ft. Lbs. of Torque.

 

[RyzRT]

Well said Ryan..............

Thank You Sir!

 

[Mopar_NoCar]

No matter your horsepower level, if you cannot get that power to the road you're just spinning while lower powered vehicles are flat walking away from you off the line. B Mason said it best when he suggested starting your 5.7 upgrades from the rear forward to get the power to the ground, then worry about increasing the engines output. As for myself I did the opposite and then proved the hard way what he said was exactly right. Because once my power level got me melting the rear tires, or should I say tire, I was not going anywhere fast off the line, it was an impressive tire spinning show, but that was all it was.

When I first saw Challenger advertisements burning down the tires I first thought that was so cool, until I was given a ride in a Hellcat Redeye and realized if he hammered it, he wasn't going forward fast off the line with his 797HP. So HP to weight ratio and forward momentum has quite a few factors involved to actually get the vehicle off the line. Most of the 5.7L automatic transmissions are fitted with open or conventional differentials using computer assisted traction control giving the owner the illusion of both tires producing traction.

That computer controlled traction uses your ABS braking system to apply brakes to the spinning rear wheel in an attempt to shift traction to both wheels.

Isn't that wonderful!

So many times I've longed for the best off the line I could possibly get and all I really needed was to apply the rear brakes? NOT!

Who honestly even thinks to achieve forward momentum and get off the line requires applying any braking what so ever to the rear wheels that are pushing you forward?

However the electronic traction control works OK, until you start increasing engine performance and you hammer it to do an off the line burn out and leave one line of rubber on the road, usually the passenger side rear wheel, how embarrassing is that coming from a Dodge Challenger!

Unless you've experienced that yourself you think I don't know what I am talking about, but those of you that have swapped to a Limited Slip Differential now know the difference real traction is.

Which brings up the next problem with traction the 245 width tires, that is really an entire subject all its own as rim width determines the width tire you can safely run on the rear. Tire width has to be matched to the rim width for the tire to sit flat to the road for the best overall traction. Which usually requires going to wider rims to run wider tires.

I started with 10.5" rear rims and 315 tires, then an upgrade to a 3.09 LSD, and still after my cam, headers and tune, I still have 0 traction and can blow the tires off and fishtail the car with the traction control fully on.

 

[RyzRT]

Now here is a really good thing about increasing your power of an R/T 5.7L HEMI, starting at 2015 you have the same 8HP70 transmission and 8 bolt driveshaft that the 392 Scat Pack has. So you can increase horsepower to around 485HP with no worries at all regarding the transmission and driveshaft HP handling capability.

Seeing as how the 392 Scat Pack is rated at 485 HP and 475 Ft. Lbs. of Torque.

EDIT CORRECTION: The above statement is not exactly 100% true regarding the OEM stock driveshaft. At the time I made the statement that was before my driveshaft center support carrier bearing failure. I thought it was more than adequate and as far as horsepower ratings the OEM 2 piece driveshaft is horsepower rated to handle the 392 Scat Pack. However the center support carrier bearing housed in a rubber doughnut can fail from the rubber deterioration allowing the bearing to come loose from the housings support, and that is bad!

You can read what I've discovered so far here > Replacing My Drive Shaft! WARNING!

Ry

 

[CaptScat345]

This is an awesome thread, Ry! I'm glad I took the time to read this before I made a post that goes perfectly with this thread.

I've just recently installed the AFE GT Momentum CAI on my 2016 5.7 Challenger RT and I'm really happy with it! I can certainly feel the engine breathing and responding better to it than the stock airbox. Life has finally slowed down enough that I could actually start doing some 0-60 runs.

I took her out this morning, down a stretch of backroads from my house and the weather was great. On my first run, I got a 5.5, 0-60. The next two runs were 5.6s and my final run was 5.5. Even though I've had my baby for four years, I've only just recently started practicing 0-60 runs with her. I was absolutely excited about getting 5.5 runs. Everything else on the car is stock. The CAI is the only bolt-on I've done to her. I'll post the time pic below.

My next step will be swapping out the OD for the LSD. I'm really hoping to be able to do that before the end of the year.

What are the best times any of you have had with your challengers at the stage where mine is currently? Has anyone gotten lower than 5.5? Am I at par with other times considering the CAI is the only thing I've done as of yet?

Dave

 

[RyzRT]

@CaptScat345

Dave, Are you spinning the tires off the line?

 

[CaptScat345]

Ry, I got the slightest semblance of a bark on my 5.6 runs but I couldn't hear any discernible tire squeal on my 5.5 runs.

 

[RyzRT]

Ry, I got the slightest semblance of a bark on my 5.6 runs but I couldn't hear any discernible tire squeal on my 5.5 runs.

Dave, What is your end goal?

 

[CaptScat345]

Just to get the most out of it with only bolt-on mods. It's still my daily driver and even though I don't drive that much, when I do it's long-stretch highway driving. I don't plan on disabling the MDS when I get the Hemifever tune because I want to maintain some semblance of respectable fuel economy on the highway. I've got my mod list pretty set as far as the rest of it goes.

BBK shorty headers
Fastman 82mm TB
180 thermostat
Hemifever tune

The 3.09 LSD swap is on the list before any of the aforementioned starts to be done.

As ol B. Mason says and I tend to agree, "just have something you enjoy and have dumb fun with" and that's exactly what I plan to do. Just have dumb fun. LOL

I'm also eyeballing the Eibach sportline suspension (just shocks, springs, camber alignment bushings and the camber arm kit).
I'm mainly just trying to make the most fun daily driver I can.

 

[MSchoo92]

Just to get the most out of it with only bolt-on mods. It's still my daily driver and even though I don't drive that much, when I do it's long-stretch highway driving. I don't plan on disabling the MDS when I get the Hemifever tune because I want to maintain some semblance of respectable fuel economy on the highway. I've got my mod list pretty set as far as the rest of it goes.

BBK shorty headers
Fastman 82mm TB
180 thermostat
Hemifever tune

The 3.09 LSD swap is on the list before any of the aforementioned starts to be done.

As ol B. Mason says and I tend to agree, "just have something you enjoy and have dumb fun with" and that's exactly what I plan to do. Just have dumb fun. LOL

Just some perspective on the fuel economy, not sure what you get with mds but my 6 speed challenger I can still manage 24mpg or so cruising at 75ish. Not sure how that’d compare to an auto with mds disabled but I’m sure you’d still have decent fuel economy - something to consider should you go deeper into the mods and want to disable it.

 

[RyzRT]

Just some perspective on the fuel economy, not sure what you get with mds but my 6 speed challenger I can still manage 24mpg or so cruising at 75ish. Not sure how that’d compare to an auto with mds disabled but I’m sure you’d still have decent fuel economy - something to consider should you go deeper into the mods and want to disable it.

I disabled my MDS feature simply because it can activate at the very time you need all 8 cylinders enabled which causes a delay in getting the power you need. Those may be rare occurrences but it does happen and sometimes it enables just before reaching a small hill causing an engine stumble. As far as long trip driving I don't know the exact mileage but I do know the ride is so much smoother because when the MDS kicks in at 70 mph cruising the exhaust sounds horrible.

Now our 2005 Jeep Grand Cherokee 5.7L HEMI Limited with it's 4 speed automatic the MDS feature is seriously irritating, I purposely bought a S1000D Diablo Sport Sprint OBDII port MDS disabler, which works fantastic by the way.

Some like the MDS feature some don't it is a simple preference.

 

[CaptScat345]

Yeah, the one time I did some highway driving with the MDS disabled I also was averaging 25 mpg. That's certainly acceptable to me if that's what I would average with a 93 octane tune.

And Ry, if the exhaust note sounds terrible with the MDS disabled then I'd definitely disable the MDS. The last thing I'd want to hear is an annoying exhaust note.

 

[CaptScat345]

In addition to the above post, with the MDS system I can be going down the highway, cruising at 80 and on day with bad air, I consistently average 30-32 mpg. On a good day, 35 mpg.

 

[CaptScat345]

Happy Labor Day everyone!

 

[wvhemis]

Upgrades to the 5.7L HEMI that do add horsepower and rear end torque, that actually push the power to ground up to close to the Scat Packs capability, do have a major plus benefit to the owner. You have a good increase in power but you are still in a lower insurance bracket with the R/T 5.7, and you're getting better gas mileage as well.

Gas mileage not so much.....