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Lots of great information here. Thanks for posting it.

My question is: Considering the cost and effort you put in, would you consider buying an SRT8, SRT core, or SuperBee model instead of doing all of this on your R/T?
 

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Lots of great information here. Thanks for posting it.

My question is: Considering the cost and effort you put in, would you consider buying an SRT8, SRT core, or SuperBee model instead of doing all of this on your R/T?
I thought about it, but I only paid $29,200 for the Daytona with Nav and sun roof option. I wanted cloth seats, no leather and I did not want all the extra weight that comes with the power stuff. I really was looking for a Daytona without the sun roof but could not find one.

If I had purchased a SuperBee I could have just changed out the Getrag Diff or less than $900 and had the same power. I just think I would have started modding that like I did the Daytona. I like to work on cars so having one in the driveway without doing anything to it is no fun. The SuperBee with a 3.55 differential swapped out would be sweet and for someone that does not want to mess around with installations IMO that is the best route to go. They are selling dirt cheap now with the 2015's just around the corner.
 

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Did you think of a CNC heads with big valves?
If the TCM was reprogrammed, any chance that 3.92diff will let you shift to 60mph in 2nd?

Just asking because I'm planning to do the same on my car but with SRT392 parts..
 

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Did you think of a CNC heads with big valves?
If the TCM was reprogrammed, any chance that 3.92diff will let you shift to 60mph in 2nd?

Just asking because I'm planning to do the same on my car but with SRT392 parts..
CNC Heads with big valves IMO are a waste of money. There are a few folks with 2009+ Eagle that got the P/P Heads and some with what they call the Big Valve along with the Cam install. To say the least they were disappointed in the results and agree that they were a waste of money. WRT TCM, I have a spare in the garage that I was planning to get Arrington to program. However, I rarely go over 4500 rpms and when I go WOT with sport mode I can hit 6000 rpms without going into limp mode. That is right at the limit for 2nd gear 60 mph with the 3.92. Just before I ordered the TCM a friend suggested that I get 275/45/20's for the rear instead of my 275/40's. The 45's are 29.7" tall and would let me hit 61 mph before 3rd gear hits.

Here is a post by someone on the Challenger side regarding Heads and the Eagle:

"Cylinder heads......... All this hoopla about CNC big valve heads are about the biggest waste of money you could spend. All said and done..... 3-4K? You need to turn more RPM to take advantage of those big valves, are you willing to spin that stock bottom end 7K? And how about all that bottom end torque you just lost......

The stock 5.7 Eagle heads (2009 and up) flow right at the 300 CFM mark @ .600-.625 lift. This is enough airflow to support 600 horsepower. 6.1 heads flow roughly the same number, even with the bigger valve. If you are looking for every ounce of power then sure, having all the ports flow identical numbers is awesome, but at what price? The stock ports flow plus or minus 3% due to modern casting techniques,(lost mold) more than acceptable to any serious racer. Hell, back before continuous five axis CNC mills, it was all done by hand, 3% between ports would have been awesome. My proof? Comp cams new MDS piece and Kooks long tube headers, no other mods except for the tune, made a gain of 108 hp on a 5.7.

As the valve, (intake for this example) comes off the seat, it opens to .100 then to .200 then .300 and so on, until it hits maximum lift, say .600. Now the valve starts to close, it sees .500 then .400 then .300 until it closes on the seat again. So the intake valve actually saw .300, .400, .500 twice, once while opening and once while closing. It only saw max lift once, .600. It is here (CFM @ max lift) where many judge a cylinder heads potential. They are correct, maximum CFM will dictate how much horsepower your gonna make, it takes a certain CFM to make a certain amount of horsepower.

However, if port flow is weak in the mid range, say .300 to .400 the motor would be an absolute dog until you get the RPM's up to where you can start using all that air. Any port (we're talking intake here) you can get in the low to mid 200's @ .300 to .400 lift is gonna have a nice fat powerband, just like the 5.7 has. I would assume the average maximum flow numbers for the Eagle (300 CFM @.600) were a fringe benefit of having the port work in the midrange area. To use the ports full potential, you would be talking in the 7,000+ rpm range. The camshaft profile would fall flat on it's face waaay before that kind of rpm. The motor, (stock anyways) could never reach that level

So the point I am trying to make is this, the heads (5.7 Eagle's) can flow enough air to make roughly 600 horsepower without touching them. Why on earth would you throw away hard earned money on a set of CNC heads with flow characteristics that you will never use.... those big valves and flow numbers kill low end power. Sure it flows 340 CFM, but what is the port velocity? Air speed... gotta have it."
 

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CNC Heads with big valves IMO are a waste of money. There are a few folks with 2009+ Eagle that got the P/P Heads and some with what they call the Big Valve along with the Cam install. To say the least they were disappointed in the results and agree that they were a waste of money. WRT TCM, I have a spare in the garage that I was planning to get Arrington to program. However, I rarely go over 4500 rpms and when I go WOT with sport mode I can hit 6000 rpms without going into limp mode. That is right at the limit for 2nd gear 60 mph with the 3.92. Just before I ordered the TCM a friend suggested that I get 275/45/20's for the rear instead of my 275/40's. The 45's are 29.7" tall and would let me hit 61 mph before 3rd gear hits.

Here is a post by someone on the Challenger side regarding Heads and the Eagle:

"Cylinder heads......... All this hoopla about CNC big valve heads are about the biggest waste of money you could spend. All said and done..... 3-4K? You need to turn more RPM to take advantage of those big valves, are you willing to spin that stock bottom end 7K? And how about all that bottom end torque you just lost......

The stock 5.7 Eagle heads (2009 and up) flow right at the 300 CFM mark @ .600-.625 lift. This is enough airflow to support 600 horsepower. 6.1 heads flow roughly the same number, even with the bigger valve. If you are looking for every ounce of power then sure, having all the ports flow identical numbers is awesome, but at what price? The stock ports flow plus or minus 3% due to modern casting techniques,(lost mold) more than acceptable to any serious racer. Hell, back before continuous five axis CNC mills, it was all done by hand, 3% between ports would have been awesome. My proof? Comp cams new MDS piece and Kooks long tube headers, no other mods except for the tune, made a gain of 108 hp on a 5.7.

As the valve, (intake for this example) comes off the seat, it opens to .100 then to .200 then .300 and so on, until it hits maximum lift, say .600. Now the valve starts to close, it sees .500 then .400 then .300 until it closes on the seat again. So the intake valve actually saw .300, .400, .500 twice, once while opening and once while closing. It only saw max lift once, .600. It is here (CFM @ max lift) where many judge a cylinder heads potential. They are correct, maximum CFM will dictate how much horsepower your gonna make, it takes a certain CFM to make a certain amount of horsepower.

However, if port flow is weak in the mid range, say .300 to .400 the motor would be an absolute dog until you get the RPM's up to where you can start using all that air. Any port (we're talking intake here) you can get in the low to mid 200's @ .300 to .400 lift is gonna have a nice fat powerband, just like the 5.7 has. I would assume the average maximum flow numbers for the Eagle (300 CFM @.600) were a fringe benefit of having the port work in the midrange area. To use the ports full potential, you would be talking in the 7,000+ rpm range. The camshaft profile would fall flat on it's face waaay before that kind of rpm. The motor, (stock anyways) could never reach that level

So the point I am trying to make is this, the heads (5.7 Eagle's) can flow enough air to make roughly 600 horsepower without touching them. Why on earth would you throw away hard earned money on a set of CNC heads with flow characteristics that you will never use.... those big valves and flow numbers kill low end power. Sure it flows 340 CFM, but what is the port velocity? Air speed... gotta have it."
Thanks about the head.. That is going to save me some money to use on something else...

Again, what about ported 392 intake and TB? I read people having some love with it..

Back to the diff..
I was reading the same with Ram's guys.. 3.73 or 3.55 will let you hit 60mph away from the redlining on 2nd compared to 3.92 where you might hit 3rd before hitting 60, but I thought it is because of the truck weight..
So, since you have already did 3.92, do you suggest 3.92 or 3.73?
I'm running Hankook Ventus V12 255/45ZR20 and 275/40ZR20
 

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Porting the 392 intake from what I hear is not worth it. There is not much to take off with this manifold like a P/P 6.1L. There is a shop in NY that does it but I have not seen any results other than what they claim. One guy say's he can feel the diff but I question how much for the price. The 6.4 SRV intake works great on these 5.7L Hemi's right out of the box. Here is a gear/speed calculator that I use. It is accurate as heck based on my data logs.

http://www.wallaceracing.com/calcmph.php

I use 5900 rpms as the maximum rpms for the stock TCM in sport mode and the 2.19 second gear ratio. Tire diameter is 28.7 for the 275/40/20. IMO the best gear is the 3.55 and if you have the $$ the 3.73. BNFY in Ohio is the only place that I know of that sells the 3.55. Actually they can do just about any Getrag diff. POC is Eric and they work mainly on LX platforms. If I could do it again I would have got the 3.55. If I keep the ride and put on a SC I will definitely get them. It is just the diff change out once the axles and stuff is installed.

The extra size P/P TB unless you get a very aggressive Cam will only get you a few HP. The 5.7L and 6.4L have the same TB. If anything you could get Fastman to P/P the one you have.
 

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Porting the 392 intake from what I hear is not worth it. There is not much to take off with this manifold like a P/P 6.1L. There is a shop in NY that does it but I have not seen any results other than what they claim. One guy say's he can feel the diff but I question how much for the price. The 6.4 SRV intake works great on these 5.7L Hemi's right out of the box. Here is a gear/speed calculator that I use. It is accurate as heck based on my data logs.

http://www.wallaceracing.com/calcmph.php

I use 5900 rpms as the maximum rpms for the stock TCM in sport mode and the 2.19 second gear ratio. Tire diameter is 28.7 for the 275/40/20. IMO the best gear is the 3.55 and if you have the $$ the 3.73. BNFY in Ohio is the only place that I know of that sells the 3.55. Actually they can do just about any Getrag diff. POC is Eric and they work mainly on LX platforms. If I could do it again I would have got the 3.55. If I keep the ride and put on a SC I will definitely get them. It is just the diff change out once the axles and stuff is installed.

The extra size P/P TB unless you get a very aggressive Cam will only get you a few HP. The 5.7L and 6.4L have the same TB. If anything you could get Fastman to P/P the one you have.
With the website calculator it is confirming, the speed will drop to 45mph with 3.55, 43mph with 3.73 and 41mph with 3.92, and the best one to get 60mph in 2nd is the stock 2.62diff
This is similar to what I manually calculated, but I thought there is a mistake since people claiming 3.92 and 3.73 are faster off the line, but the calculation is saying otherwise..
 

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Great thread! I can't believe this is the first time I have seen it. You've done well and you're making great power for the money you spent.

What really surprises me is there haven't been any SRT owners on this thread being hateful...anytime anyone hints that their RT with some mods is competitive with an SRT it starts an all out war.
 

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TKS, If I did not have the 3.92 rear there would be a debate on straight line performance but overall after driving a new SRT, they are the best ride quality car in the Dodge lineup IMO.
 

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TKS, If I did not have the 3.92 rear there would be a debate on straight line performance but overall after driving a new SRT, they are the best ride quality car in the Dodge lineup IMO.

Yeah the 3.92 rear is one of the only mods you see a significant time reduction with.

True, the SRT suspension is great...it makes for one hell of a ride.
 

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This is a great thread, however, I do have one question...

Do you have emission testing and inspection where you live, and if you do are there any issues or CEL lights coming on.
 

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This is a great thread, however, I do have one question...

Do you have emission testing and inspection where you live, and if you do are there any issues or CEL lights coming on.
I live in Knoxville TN. LOL If you pay the wheel tax and renew the tags they do not care what you drive! I did not get any CEL lights with either the JBA Shorties or the ARH LT's. Both companies make great high flow cats.
 

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This post is great, it gives me more to think about for down the road. Once I get the intake, T-Stat, DiabloSport and exhaust done I am basically done with the "easy" stuff. From there, I'll have to do my homework to get the best bang for the buck. The pre-Eagle 5.7's could really get up there in power as well, it just takes some planning. I'm hoping to put down 400+ when it's all said and done.
 

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This post is great, it gives me more to think about for down the road. Once I get the intake, T-Stat, DiabloSport and exhaust done I am basically done with the "easy" stuff. From there, I'll have to do my homework to get the best bang for the buck. The pre-Eagle 5.7's could really get up there in power as well, it just takes some planning. I'm hoping to put down 400+ when it's all said and done.
I started my modding with a goal of 400+rwhp. Made several errors along the way but it was fun.

I have been doing research on my next build, most likely a SC, but came across some impressive builds for the pre-eagle Hemi's at High Horse Performance in Delaware. They have a heads/Cam package showing for the 6.1L but I am sure it would cost no more for your Daytona.
 

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Tacamo,

Thank you for posting this thread. I had been considering a similar setup (sans heads) for my 14 R/T blacktop. I don't want to try and reach MY14/15 SRT power but I would like to see the car come in somewhere around 420-430 HP at the crank. My planned build was as follows:

BBK 1 3/4" long tubes (2 3/4" collector)
BBK catted 2 3/4" mid pipes
Diablo Tune (91 canned on 93 octane) with eventual custom tuning
LMI Intake (most likely the true CAI)
180 degree thermostat
Snow Performance Stage III methanol (to really crank the timing on the tune)

Eventually I was going to add a cam but considering the cost for installation and dyno tuning I may forego that option and simply enjoy the above package for what it is. The good thing is that with the mods listed above, it would do very nicely with a centrifugal blower (especially with the meth injection). I would definitely stay with the 3.06 gears to not roast my tires completely on launch.

Again, thanks for putting this together and sharing the pitfalls of what you went through. I think all of us have been guilty of modding without having a full plan and hopefully this helps others avoid the same thing.

Cheers!
 

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Thanks and your build sounds like a good plan. I do not know much about BBK Headers on the Charger but the filament was not that great when I had my 2011/2012 Mustangs. The closest competitor in price would be JBA. Sticking with the 1 3/4" instead of the 1 7/8" is good because I have seen dyno's where the larger ones do not work as well. You might want to search the internet and forums for BBK and JBA header systems for the charger. Both companies like to brag about their gains on dyno's but they are in house dyno's and test conditions IMO are questionable.:beerchug:
 

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It's interesting that you had fitment issues. I used BBK shorties on an older SN95 I raced and they were pretty good. I'll definitely do some more checking before making up my mind. The big deal is to stay with 1 3/4" as noted but what's really important to me is to avoid a 3" collector since I'll lose scavenging with something that large. If I was going to cam I could see it but that would either necessitate a gear swap for torque multiplication or a higher stall which is kind of out of budget. I just want something with a bit more low end kick that doesn't take a bunch of supporting mods to be effective.

I also have to agree with you on the dyno gains. I would expect catted mids and long tubes to add about 20 RWHP on a good day not the 35 that BBK shows for long tubes and catless mids.

I'll be in touch and let you know how it goes once I get everything done. Thanks for jumping in and responding!
 

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Since you already have the daytona, the mods make more sense, UNLESS you are not too upside down, then you may consider jumping for a 15 SP, or a used 12-14 SRT, but either way, I think if you enjoy modding, you won't lose and its a great choice for you. Congrats bro!
 

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I thought about it, but I only paid $29,200 for the Daytona with Nav and sun roof option. I wanted cloth seats, no leather and I did not want all the extra weight that comes with the power stuff. I really was looking for a Daytona without the sun roof but could not find one.

If I had purchased a SuperBee I could have just changed out the Getrag Diff or less than $900 and had the same power. I just think I would have started modding that like I did the Daytona. I like to work on cars so having one in the driveway without doing anything to it is no fun. The SuperBee with a 3.55 differential swapped out would be sweet and for someone that does not want to mess around with installations IMO that is the best route to go. They are selling dirt cheap now with the 2015's just around the corner.
I must of not found any cheap Superbees. I got mine in October for 48k. Obviously because it was fully loaded and all that, but even the base price 44k, were you referring to used ones?

Also, nice car by the way bro! Daytona's are cool :clap:
 
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