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Can anyone ask them if there is any mpg benefit (or possibly an explanation on how an mpg benefit might emerge) when accelerating at around 2700 rpm vs. gradual acceleration at 1800-2200 rpm, as far as achieving good city mpg figures in typical use?

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The SRT Engineers Chat Session will take place on Wednesday, January 26, 2011, from 5-7 PM EST.

To post questions, you have to register at the site. Here is the link:


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I am sure alot of people ask them about the stalling issue - and I am also sure they won't have any answers.

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I wonder who posts the first IE up hold question? ;)

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Here are all of the questions and answers from tonight's SRT Engineers' Chat Session. lot of discussion concerned the 6.4 (Part 1 of 4):

Flow wise, how does the new 392 intake manifold compare to the old 6.1 manifold?

I don't have airflow box numbers but on the dyno on a 392 engine, the two intake manifolds make the same horsepower at the same engine speed. The new manifold excels below 4900 rpm where it makes a lot more torque which is more tuning that absolute airflow.

I have an 2009 Challenger SRT, automatic. It seems to have two different issues starting. Twice (once the outside temperature was high 20s, the second time outside temperature was in the mid 40s) I've used the push button start from inside the vehicle. The starter turns over, but doesn't engage the engine. To get the car to start, I have to pull out the push start button and insert the key. Today when it happened, the car started for about two seconds then quit. Then did the starter thing. It started fine with the key fob inserted. Any ideas on what is happening?

The second issue is the remote start does not always remote start. It seems to happen more on colder days, than not, but this is not always the case. I cannot find a definite pattern for when the remote start works and when it does not.

Thank you for any insight and for answering my and others questions.

Regarding your issues starting your vehicle: the starting system is pretty complex and would be very difficult to diagnose remotely. I would suggest working with your local dealer and familiarizing yourself with the conditions listed in your owner’s manual with regards to when your remote start will and will not work.

On an '08 SRT Charger, why is there so much bump steer? Would you have a suggested solution to this problem in the way of a fix? Perhaps a certain popular kit, that involves bushings. This bump steer can get a little hairy at times. An example would be those times when you get out of the groove a little at the big end of the strip. The car starts going all over the place.

Based on the signature, your vehicle has had several modifications done to it. Any changes to the front tires, tension links, suspension bushings, or power steering could have a negative effect to bump steer. We would recommend inspecting your front suspension bushings for any excessive wear, and replace them as required.

Is the 2011 6.4 Hemi based more from the previous 6.1 engine (like the MP 6.4 crate engine) or is it more based from the latest 5.7 Hemi ? In other words, is it a stroked 6.1 or a bored and stroked 5.7 ?

Thanks so much for taking the time to come visit with us and answer our questions..

The 392 is a combination of new, modified 6.1L, and carry over 6.1L and 5.7L We use what works for us. Most parts are new.

I know you can't comment on future products, but are the ideas of "SRT", "Charger" and "AWD" mutually exclusive, only in pairs, is there hope for all three from the factory in this new generation?

You answered your own question in your question...can't comment on future products!

Any resolution to the random engine stalling?

Any issues that affect your vehicle’s performance should be taken immediately to your local dealer. It is possible that there could be a software update which applies to your vehicle but would be impossible to diagnose through a forum such as this.

I'm picking up my IE 392 Challenger on Thursday what is the best way to break in the motor and when should I do the first oil change?
2011 Challenger 6.4 6 Speed

Thanks for purchasing a 392! Actually the car manual has the best method for running in the engine to give the best results. You can't go wrong by following the manual on this one.

Thank you all for taking the time to answer our questions and share your knowledge with us.
My question is in regards to the new MPTCM for the SRTs. Other than already being pre-programmed with the 3.06 gear ratio, what makes this more advantageous than the previous MPTCM? Can you share some of the Specs with us? Shift points, TC lock, line pressure etc..

Thanks again for taking the time to be with us.

The two part numbers are very similar except for the gear ratio difference you mentioned. In response to customer requests we introduced an SRT version of the 5.7L Performance TCM. The calibration was optimized for use with the OPAR Performance Torque Converter and also includes the hold in gear feature. Performance gains will be greatest for those customers with a higher slip converter.

When are we going to see a new 392 Charger?
Please tell me they'll skip the ugly color schemes.

Know you've heard this before - but won't talk about any future product.
Why did the 392 Challenger receive a different front chin spoiler and what added benefit does this do compared to a 2010 SRT8 Challenger chin spoiler? Will a 2010 SRT8 be able to utilize this new part or will the front fascia also have to be replaced?

Thanks a bunch and will always remember the SRT driving experience!

The new front fascia integrated spats into the fascia to give a more pronounced front end. The new part chin spoiler matches profile to the old fascia, but it will not work since the attachments are different location and size (however close).

Greetings and thanks for taking questions! Will the 07' and up MTCM for SRT's work as well in cars with 3.73 or 3.91 rear gears as it does in 3.06 equipped cars?
And what exactly is the difference from the stock TCM to the MTCM? Thanks!

The TCM calibration contains the gear ratio and it must match the actual gear ratio of the vehicle. If the gear ratio does not match it will go into limp-in mode. See post #70 for the differences between the calibrations.
First and Foremost a Sincere Thankyou for allowing this 60 year old to relive his youth of the Muscle Car era! I have not had this much fun since 1967 to 1971! My 2010 Dodge Challenger SRT 6-spd is a BLAST to drive! I have 2000mi's on it b-4 it went into winter storage.

My first question is the Tremec 6060's gear nibble in 2nd and 3rd? If I double clutch there is none, but with normal shifting below 2200rpm there is a persistent nibble, but at 3500rpm it appears to float smoothly into gear. I have called Tremec and their response was YES there is an issue, contact your dealership. My dealership claims there is NOT! Or is heavier loading needed(more break-in time)?? Per my tranny's serial# TUET 10430BL2493 P05038209A6 04918 it was produced 11-24-2009 on 3rd shift

Also the wheel hop issue? Does Mopar have a suggestion to a more solid fix than heavier motor mounts? Such as a No Hop kit, or a Mod from Mopar?

The cars we have shift with the precision that we have come to expect from the TR6060. Personally I like to feel each and every segment of the shift rather than a numb/dead stick. I've heard some people describe this a notchy, but if your getting nibble that's something different. If the car is cold you might feel something and I would consider that normal and par for the course on a high performance trans. I don't know who you talked to at Tremec but we have not seen an issue on a warmed up car. If you are seeing an issue the dealer should be able to reproduce it.

Is there a way on a 2009 challenger SRT8 to permanently turn the "ESP" off? And not each time i start the car?

Sorry, permanently turning off ESP is not a something that can be done in our vehicles.

You will need to press and hold the button each time you want to turn it off.

Will the 392 share interchangeable parts with the current 6.1?
- Will the new Android phone apps work with 2006 300 srt Bluetooth software?


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Part 2 of 4

Here's a quick summary:
PT : 6.1L vs 6.4L is all new - some minor interchangeability misc parts like rocker arms but mostly all new.
Body : Pretty much c/o (except for front fascia attach)
Interior: New seats and seat tracks (can't put '11 seats in '10)
Chassis: New Front/Rear cradles -- Front (new steering / eng mounts, camber), Rear (park brake, susp links)
Electrical : c/o with new alternator and starter (Still CAN based)

As for Android Phone question - not sure

hanks for taking the time to be here and answer our questions.

I have a 2009 SRT8/6SPD Challenger that I use as a track toy for drag racing and road racing.

Can you tell us what the 2011 6-spd gear ratios are? I heard that 5th and 6th gear were changed to bring down the speeds and make them more usable but have been unable to find the detailed ratios for each gear.

The trans ratios are unchanged for 2011.

Can you tell us what changes, if any, were made to the 2011 Challenger rear cradle, cradle bushings or suspension geometry to address wheel hop?

There were 2 changes that reduced occurrence
New conical hydro-mounts on eng allow fore improved damping on driveline torque reaction.
Changed rear cradle (front bushing) to taller snubber - were shorter design for '10

ok guys, here's an abstract one for you, or to maybe forward on.

where in the (2007 vintage) FCM-CGW is the vehicle's advertised engine displacement stored. for example, a 5.7 car, flashed as a 6.1 in the PCM. it's still recognized as a 5.7 by the star scan and star mobile. the PCM and ABS recognize it as a 6.1 though in their configurations. i don't see it in the FCM configuration, does it read it from the VIN?

Due to their respective calibrations, the ABS and PCM communicate to each other via bus message to let each other know the important configuration bits. Additionally, if you can find the 5.7L configuration via a diagnostic tool, that would be the configuration where it would say it's a 6.1L

What are your thoughts on the Eaton TVS supercharger?

It’s the most efficient supercharger that I've ever read shows that supercharger technology is certainly not primitive and this particular supercharger is nearly as efficient as a turbocharger. Good Job Eaton!

Thanks for listening and answering our questions, i have a 2009 charger srt-8 the tranny still upshifts out of first at ant time it wants. Will the new mtcm change that and what are the shift points? Part #on the box is p5155177, part # on the actual controller is pp5155179aa, have not installed this yet because the dealership installed the first one by the instructions and fried it, Im now told just to install it at home and run the adaptives, yes or no, thanks again.

P5155177 is the kit part number. P5155179 is the part number for the actual controller. The new TCM does have the hold-in-gear feature that will prevent it from upshifting in Autostick mode. The shift points are the same. Sorry to hear your first controller got damaged. The instructions do warn against initializing the controller as that will wipe out the MOPAR Programming. See below.


Most customers should be able to install the part themselves, just be sure to follow all the instructions included with the kit.

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Part 3 of 4

The 2011 Challenger has a revised clutch and transmission input shaft. What benefits does this revised setup provide?

The clutch has a bit higher clamp load to handle the extra torque of the 392. The input shaft changes to a high strength material. Note that the clutch splines change from a 26 tooth to a 10 tooth so they are not interchangeable without also changing the trans.

The 2011 Challenger advertises more camber from the factory for improved cornering. Was this accomplished through adjustable upper arms, revised arm length or mounting changes?

Revised with revised A-arm mounting, revised lower control arm length, revised lower shock attachment (due to new kinematics).
It is much improved for tire patch during cornering and also improves tire wear.
have a 2009 Challenger SRT8. Why doesn't it have a factory shift light? When will one be available that you do not have to cut into factory harness? (aftermarket)

Request that one become available with launch light and red line?

Even my 1990 Dodge Dakota has a factory shift light?!

Actually, we do provide an upshift indicator in the EVIC of your instrument cluster.

What is the safest way to gain power in the 6.1, other then going with a SC or turbo?

Move to a lower altitude.

Hello team SRT, at 55k miles my 300 is as strong as ever and has required very little maintenance and basically zero repairs. Thanks for making such a great car, it's definitely driven like you intended it to be.

Two questions...

1 - You have to admit the other American manufacturers are doing forced induction, is there a corporate mandate against superchargers at Chrysler? No profit in it???

2 - Did you guys ever share your thoughts on the bad calipers you got your hands on? Finding bad pistons on the front calipers is still happening. Have you shown them to Brembo, and what was their response???

1) Sorry we can not talk about future products.......

2) As for the calipers we have provided the parts to Brembo and have been working with their engineers to try to understand the issues with those parts. We still have not seen any warranty claims similar to what we have seen on these parts.
The new Challenger 392/6.4 has a lighted trunk release button. Would I be able to swap my current trunk release button for the new one?

I wouldn't recommend it because of the wiring differences and the connector change that you would need to incorporate.

6.1 SRT8 with Positive Displacement SC, SRT4 2bar MAP, stock Throttle Body & Electronics

This happens on a lot of cars with this configuration. During highway cruising, cars will randomly throw DTC 2173 - High Airflow/Vacuum Leak Detected (Slow Accumulation). I read that this may be caused by the calculated MAP value being less than the Gas Flow Adaptation value.

ANY info about the detection process or Gas Flow Adaption or what needs to be altered calibration-wise?

More than likely your new higher pressure Map sensor is not scaled correctly in the controller. There are a lot of calibrations affected by the Map sensor that Diablo chips do not have access to.
1. I need to understand completely, the good and bad features of OHV and OHC.

if an engine ohv gets to be smaller, simpler, more durable, and manages to make more power with less rotations, I think it's a real piece of engineering
Because most developers prefer to use OHC? marketing? the purpose is specific power, rather than the specific power has a purpose?
OHC technology is snob-tech?

All the details you can give, thank you very much. I currently live in Europe and I want to explain this in which I participate fóruns to go off many false stories that are created based on bad pride. They are amazing, believe me!

The HEMI engine has a natural advantage in comparison with other ohv engine? in the background, you may get more power of a HEMI OHV than a GM OHV with the same characteristics? (I´m thinking in the LS7...)

It is possible HEMI 4 and 6 cylinders? ...
Could be a good idea for other Dodge line with the aura that is so necessary to attract customers any brand.

(Thank you very much)X 100

2. Please tell Marchionne not think excessively on cost optimization, think first obtaining profits, which is undoubtedly creating a distinctive aura of its own and it becomes interesting products the consumer perspective. He has a brand on the world waits anxiously for his resurrection, which is Alfa Romeo. The new Giulia is to be RWD, everyone feels a little disappointment in relation to this matter.
But the most important point is undoubtedly the use of Busso and Boxer Twin Spark. The 3.0 V6 Busso has a fantastic and addictive sound, the best for me.

It´s important to use the new territory (USA) to establish new reality and erase the bad recent past.

Alfa Romeos with aura of small Ferrari or Maserati, would be a mountain of money for the Chrysler-Fiat group. The Germans sold too, must be balanced.

Sincere wishes for success for Chrysler-Fiat!

Real tough question to answer without a text book. The Hemi stayed with a cam-in-block because of simplicity and low cost and because of the high flow characteristics of the Hemi head.

My question is regarding the significant performance difference between the 6 speed and automatic SRT's. Recent data logging by several 6 speed owners shows a drop in timing while shifting at wide open throttle and seems to be the culprit in the difference. My wife with no track experience ever was able to run a 13.6 on her third pass in her R/T to my 13.5 in my 6 speed SRT8. I have only managed that time twice out of 25 runs while slipping the clutch as best I can and with no loss of traction. All the stock automatic SRT's I have seen run, consistently make passes in the 13.1-13.2 range.

1) Is the timing being dropped the main reason why there is almost a 1/2 second difference in 1/4 mile performance between the automatic and 6 speed SRT8?

2) How detrimental to the transmission would it be if someone was able to tune their car to adjust for this timing drop?

Thanks for the great cars! I really loved seeing the 2011 Challenger and Charger on the Hemi Highway tour, and really like the direction Dodge is going with their products.

On the 6.1L, there was a non-linearity on the low end torque. The auto did a good job hiding this non-linearity due to torque converter multiplication. All testing done by our group confirms the 6.1L auto is quicker (stock) by 0.2s in 1/4mile.
-- The new 6.4L is a different story. We worked aggressively to ensure the torque curve was very linear. Our drag test numbers confirm that both are within hundreths now.

Would there being any hesitation with the new 6.4L Hemi with MDS upon take offs or acceleration? Being that the 6.1 has the straight build she pulls and has no hesitation off the line or upon the roll on speeds.

Nope, your all set. The minimum speed for MDS in the 392 Challenger is 35mph. Transition speed from V4 to V8 depends on how far you press the gas pedal. Faster transitions with more gas the end you should not feel any hesitation.

First off thanks for taking the time to answer our questions. Any chance of having more gear options in the Getrag....maybe something along the lines of a 3.23-3.55? Seems like such a big jump from 3.06 to 3.73

Honestly we've gone at this one a few times and it hasn't made much progress. I guess we spent too much time working out the upgrades in the axle to handle the 392 engine. Not that we've given up. If I recall correctly from previous discussion something around 3.3 has the hottest demand.

What do you guys think? If you were going to put down some hard earned cash, what ratio would you want most?

What is the purpose of the plastic belly pan on the Challenger? Aerodynamics? What would be the negative effect, if any, off removing it?

The plastic belly pan does indeed help the aerodynamics of the vehicle. If you notice it also holds you brake ducts.

What new capabilities are provided with the new engine management controller in the 2011 Challenger? What capabilities are lost?

More regulatory capability for diagnostics and feature content is typically what drives a new engine management system. Basically new name/new box...

What is lost? Hackability.

s any mpg benefit (or possibly an explanation on how an mpg benefit might emerge) when accelerating at around 2700 rpm vs. gradual acceleration at 1800-2200 rpm, as far as achieving good city mpg figures in typical use?

Generally speaking, you'll have better mpg at lower rpm unless your seriously lugging the engine. Best city FE = light pedals, short shifts and get it into 5th or 6th gear as soon as you can.

Once again I would like to thank you guys over at SRT for taking the time and patience to answer all of our curious questions. We feel honored that you have chosen our wonderful forum.

I realize the bean counters do everything possible to keep these extraordinary machines competitively priced, but I'm sure that your also aware they are still far out of reach for the majority of your customer base. This recent economic downturn has left a lot of us craving for the raw power and the attention an SRT package brings.

So cutting to the chase here's my question: What do you guys think about upbadging? meaning applying SRT visual cues such as OEM SRT hood scoops, badges, bumpers, fascias, wheels and fake Brembo caliper covers to a non-SRT vehicle. Do you believe it gives the SRT a bad image and tarnishes your reputation when a lesser car such as a Camry, humiliates an SRT clone out in the streets?

I have noticed this has been becoming a recent phenomenon lately and would like to know your take on it. Thanks

You'll never get rid of the clones. I must say, I grin when I see a V6 with an SRT8 hood, its definitely a huge compliment to the SRT styling. Anyone that knows performance GM/Ford/Dodge knows the clones in each ... the people who don't know are of no concern to me.
....someone having trouble selling an SRT Design PL SRT4 ??? LOL

When will the SRT group fix the issues with the Challengers stalling under braking/turning?

1) During a roundtable discussion earlier, the group acknowledged the issue

2) After my personal conversations with Jonathan at SRT, I got no help

3) It is still being ignored, or at least we as the consumer FEEL that way. Please set me straight if I am incorrect.

4) We have innumerable recounts of this issue from other Challenger SRT8 owners here and on multiple other forums. This is real, it is WIDESPREAD, and it is dangerous.

I love my car, but it has the potential to cause great damage or even kill my family as it does this. As you know, we can't just restart it... we have to STOP completely, put the car in PARK, then cycle the ignition. We can't even just pop it in neutral and restart while coasting... if the car starts, the tranny does not engage until it is restarted in PARK.

I want to keep faith in Dodge & SRT, but this is a SERIOUS issue, and there should be an honest RECALL of our vehicles before someone dies by stalling in a turn in front of oncoming traffic.

This is not an issue easy for us to replicate, I have been unable to do so with my dealer. I was advised to just go back to the dealer, let them diagnose it, then they would follow up with SRT. That is not a good idea.. they can't replicate it, and do not seem to have the diagnostic tools or skills to figure out why this happens.

Sorry to hear about the issues that you are having with your vehicle, but it is nigh impossible to properly diagnose a vehicle issue like this on an chat forum. As I said in an earlier post, I would strongly suggest you take your vehicle to your local dealer. It is possible that there is a software upgrade which applies to your vehicle. Additionally, if the problem is persistent and the dealer is unable to solve the issues, there is a process where the dealer network will interact with the design team to diagnose the issue. If you have taken it to a dealer but are not receiving the appropriate level of attention or expertise, I would suggest you try another dealer.
is there any way to get a flash file for an 06 srt instrument cluster that will include the new performance package pages.

now i have all the flashing tools but if i flash my current cluster with 08 +software the cluster stops working because it can no longer receive information from the pcm. however the digital screen will work and the performance pages exist. but the guages don’t work. again they are not receiving info. SoIi obviously have all the flashing tools is there any way to add those features to an older model cluster. My next step is 1 swop out pcm for newer model type i.e., 08+ and or
swop out fcm setup for a tipm setup found on newer 08 plus vehicles. when i mean swop out fcm I mean rewire etc.

Unfortunately, there is no software flash available for the performance pages prior to 2008My. Also, the two sets of hardware are not compatible with each other.

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Part 4 of 4

Can you share this information for the 2009 and 2011 Challenger SRT8 6-Speed?

I only have the 09 Challenger info right now. The only difference are spring rates, front is 260 lbf/in and rear is 653 lbf/in.

I know they are Federally mandated at time of production & sale, as I used to install them on Grey-Market cars in the 80's, but how can we disable the excessively loud, mind-numbing "Key in the Ignition" chime? I've been thru the service manuals numerous times, with no luck...not to say I didn't miss it. Is it a "Programming Thing"? Do the police Spec cars have them? Thank You, D.C.Winters in Colorado

Due to the "Federally Mandated" nature of the chime, we cannot sell a vehicle without it and thus, we don't have a programming trick to turn it off or turn down the volume. Sorry about that : (

You can write your congressman though...

Does the new 392 use the same piston and rod material as the 6.1? (powdered metal)

The pistons and rods are different between the 6.1L and the 392 for geometry. Both rods are powdered metal. All new piston casting and all new rod forging.

Can you provide part # for new motor mount on 2011SRT Challenger?


Is this improvement the result of the new manifold, a cam change, or tuning in the ECM?

All of the above! The 392 has a much better intake manifold that generates a lot more torque below 4000rpm, yet still pulls like crazy >6000rpm. Cam profile, larger stroke, larger bore, and a great calibration team!

Don't really have a question--I know you cannot talk about future products. So, here's a request. Please bring the Viper Powered Challenger to market!!

.... write to Dodge and demand it. The one we have is getting lonely and needs some siblings !

Is the 2011 6.4 a completely new engine block different from the 6.1 block and capable of a larger bore that the 6.1 block

First of all, why is there a bug crawling on your page?

The 6.4L block is an all new casting with different machining. The 6.4L bore is larger by .9 mm but the block is not designed for bigger bores than that (even though people can and do increase the bores).

Yes, that is accurate even though it is kind of hard to see with the scaling. It should line up to 470lb-ft @ 4200rpm.

09 Challenger SRT8 automatic.

I've looked all over and found different answers. So, what percentage of drive train loss are we looking at?

Well if ya got some time we could definitely spend a long time going over this broad topic. The hard truth is it depends. I know that might not be what you want to hear but I'd be doing you a disservice to tell you some simple single number. The parasitic losses of each component can change rather dramatically depending on several variables. Obviously temperature has a big effect and each part responds differently.
rpm and torque also have a big impact. Most industry standards look at this from a fuel economy point of view so the torques are very low compared to what you might see on a track or a dyno run. The big hitters in the drive train are trans and axle. A manual tran is very efficient and will typically be better than 95%. An auto trans is not nearly as efficient but still better than 90% when the torque converter is locked up. If the converter is open all bets are off. The axle has a bit more losses than the manual trans due to the heavy fluid and sliding interface of a hypoid gear set and ends up somewhere around 92%. Tires and bearings strip off a good deal of energy to but I digress. To make a long story endless... A typical dyno run uses 15% losses for a RWD car and that's a pretty good ballpark number.

Perhaps if the question was introduced this way: What, in the past, has been the reasoning in the past SRT8 models and the current 392 models to not super/turbocharge the engine from the factory?

There was lots of pressure on getting the bigger hemi on the cubic inches - above 5.7L. Speed to market also plays a major part. The 6.4L was the natural bump from the 6.1L as we went to a common FEAD with the. 5.7L.

On average, how much more gas is consumed from the 6.1L than the 5.7L? Is it much of a difference?

Fuel consumption varies from driver to driver and from drive cycle to drive cycle. The two engine packages are roughly within a few MPG's of each other according to the federal ratings.

You guys were out testing at Speedworld in Az.without details were satisfied with the testing of the 392 Challys and did you break any axles? This is what I'm finding as the weak link with irs.

Busted.... we were out at Speedworld last week. Love that track. We completed hundreds of runs on the 3 cars we brought. Did you happen to catch the massive smokey burnouts and 600 lbs of ballast we placed in the cars, trying to break something.... Not one broken part all day -- as rugged as it gets gents! We are very pleased with the results on the track..... I'm sure you will agree when you run the 392.
Did I mention I love my job !

Is the "Fuel Saver Technology" on the 392 the same thing as MDS? If so, how come you didn't just call it that? Thanks again!!

Yes they are one in the Marketing Term.

Can you define what a leak down check is? Am i looking for an air leak around intake area? Also what are your feeling about installing a cold air intake? I have heard the stock air box is as efficient as the K&N CAI. Your thoughts please.

A leak check is a diagnostic test with special equipment to measure the sealing of the rings and the valves. MOPAR sells a cold air intake but the stock parts
is pretty good for filtering and low restriction.

Can you share this information for the 2009 and 2011 Challenger SRT8 6-Speed?

Same motion ratios.

2009: 261 front, and 669 rear

2011: 284 front and 778 rear

I’ve heard the there was a difference make in the ring gap of the pistons in 2009. before that everyone was saying that 6lbs of boost was safe to run when supercharging. With this new ring gap change I’m hearing 10lbs is safe with a good tune.. any thoughts?

Really? I'd love to see that data!

Are the 2006 6.1L injectors the same as 2009 5.7L Eagle injectors?

The current 5.7L injectors are the same as the 6.1L injectors.

What do the 2011 392 injectors flow

470HP worth

I have a 2008 Charger SRT8, and when backing up with the wheels turned all the way left or right, there's a vibration/shudder in the steering wheel.
Dealer states (starOnlineResult) that this condition is felt due to the harder rubber composite in the Goodyear Formula 1 tires in cold weather.
I've driven in cold weather before with other high performance vehicles/tires and never experienced this issue, why on these cars, and why with these tires ?
Do the newer vehicles have different high performance tires now ?
Can we get a recall on these tires for replacement tires ?

The pop is caused by front castor. There is nothing wrong with the vehicle, or the tires. You are feeling stick/slip on tire patch as it differs left/right. The dealer is partially right that the vibration is induced at tire patch. As for competition, all high castor vehicles have this same condition when reversing at full lock on steering.

My only question is what is the big hold up with getting the sold 392 IE orders to dealerships.

We started building right before holiday, keep in mind new Charger launched at same time so plant has to ramp up slowly to ensure quality . . . etc. we are shipping to our eager customers.

Also, why do I have a squeal when under light breaking? Been to the dealership about this twice, and both times I was told they are racing breaks and it's just the nature of the beast. Upon researching, It appears to be an issue with the shim vibrating.

Your dealer is correct. Slight brake squeak is possible if they aren't being used to their full potential. For the brake squeal, you should try braking harder to increase the pad temperatures. In the winter, the pads drop below their normal operating range. Drive the car harder.

You ran a 12.44 @ 110mph at Infineon with an automatic 392. Did you guys touch anything on the car at all in terms of tune or fuel type do achieve that time? 12.44 is damn fast for this car.

What is the best time you have run with a manual trans?

We didn't modify the car at Infineon at all. It ran with F1 stock tires and standard premium fuel (91 octane). The manual and automatic both ran 12.6 flat last week. (temps were a little higher). The 392 is a beast on the dragstrip -- blast to drive !

What is the best time you guys have gotten out of a non street legal tune with the 6.4.

The irony is that we only test street legal tunes on our tracks. In truth, we go to the tracks to test our production tunes/chassis for track durability to ensure when you go on the track, there are no surprises.

Is there a reason SRT doesn't go to a tire that's wider than a 255 in the rear from the factory for L-series cars?

It's always a struggle for design office to use a smaller, fuel efficient tire on the base car, and nice big, wide performance tires on the SRTs while using a common wheel house and make both look awesome.

Now that Ralph Gilles is the head honcho over there in Design Office, and in charge of the Dodge Brand, maybe he can put his magic touch on some new patentable solution! Go Ralph!

Did you guys get a chance to throw some drag radials on a 392 and run it by any chance?

Yes we tried the new Nitto 275/40s. The F1s (stock) were quicker than the Nittos - no lie. We were launching the manual at 4500rpm with medium clutch release. It may have something to do with overall driveline changing with change in tire RPM.

Can the new 6.4 heads be used on a 6.1 block? How do they compare to the 6.1 and eagle heads?

Thanks again everyone for taking your time to come on and do this again!!

We started a pretty great racing series, how about you guys put together a car and come out an get beat up on by your customers!!

The heads will screw on but there's differences for chamber volume and valve heights so they are not an easy switch. The new heads flow more but I don't have the numbers.

What does the new 6.4 fuel pump flow

200 L/hr

What do you think of installing a 5.7 police package oil cooler on the 6.1?

During the development of the 6.1L Engine we did evaluate the need for an engine oil cooler. Our testing resulted that we did not need the oil cooler. We did find that going to the 392 that it was required.

Premium Member
2,418 Posts
Q - My only question is what is the big hold up with getting the sold 392 IE orders to dealerships.

SRT Engineers - We started building right before holiday, keep in mind new Charger launched at same time so plant has to ramp up slowly to ensure quality . . . etc. we are shipping to our eager customers.
IF that were true, Larry (Valataria) would have his by now!!!!

Premium Member
1,556 Posts
SRT Engineers said:
What is the safest way to gain power in the 6.1, other then going with a SC or turbo?

Move to a lower altitude.
WTF? Yeah I know it's true and funny but come on guys...:fight:

1,077 Posts
I kinda like the wit in their answers. :browsmiley:

What irks me is people ask over and over again about future products when it was clearly stated don't ask because they can't comment. :bash:

Premium Member
3,548 Posts
What irks me is people ask over and over again about future products when it was clearly stated don't ask because they can't comment. :bash:
My 5th grade teacher always reminded us school kids that there was no such thing as a stupid question. That Q&A session with the SRT Engineers is testament to just how wrong my teacher was. Because of numskulls asking downright silly questions, the more poignant questions got left unanswered due to time constraints.

.:::: just shaking head ::::.

I kinda like the wit in their answers. :browsmiley:
Yeah, "Move to a lower altitude," "Go read the manual" and my favorite, "Why is there a bug crawling next to your name." All pretty funny.

7,566 Posts
Good to know they like the TVS2300 (Magnuson) supercharger haha.


LX Padiwan
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Originally Posted by fargo59

what are your thoughts on the Eaton TVS supercharger?

Its the most efficient supercharger that I've ever read shows that supercharger technology is certainly not primitive and this particular supercharger is nearly as efficient as a turbocharger. Good Job Eaton!

3,532 Posts
and they answered the break squeal question. I always said the squeal was caused by the brake pad vibrating against the caliper piston or the mount. Its what ive been taught and what Ive found when I put the brake squeal mush on the backs of the pads. their answer was to use the brakes HARDER to heat them up.

well, the two ideas (theirs and mine) are consistent cause when you heat them up, the metal expands and then the space between the two parts that are vibrating closes resulting in no squeal. so heating them up stops the vibration by making the clearances tighter. the brake squeal goop just dampens it.
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