SRT Engineering Chat HERE on September 9th!

[Westxsrt10]

I'm having a problem with the CEL tripping on my 08 after the installation of the Belanger header exhaust system. I have checked the entire system over many times for leaks, pinched or overheated wires ect. These two codes keep coming back. PO 420 "Catalyst Efficency below threshold" Bank 1, Bank 2. Can my stock ECU be recalibrated to stop the Check Engine Light from appearing? I know of others have this exact proplem.

 

[Mopar Boy]

if you have a Gen IV you should always run a 0W-40 or 5W-40 unless at the track when a 15W-50 might be in order

Does that hold true for the Gen 1/2 motors as well? If not, what is recommended for the older cars street and track?

 

[SRT Engineers]

viperbilliam asked: "How different is the exhaust system from Gen III to Gen IV? They appear to be very similar. The only difference I know of is the air gap header. Mufflers, cats, and diameter sizes the same? If so, how do you keep the resonance down without the crossovers?"

The systems are very similar but obviuosly, the Gen IV system no longer has the crossover pipe. The catalysts and mufflers are functionally the same. We were able to eliminate the need for the crossover pipe because of the Gen IV VVT system. Cam position has a big influence on exhaust sound/noise and we managed the system noise levels in this fashion.

 

[SRT Engineers]

I'm having a problem with the CEL tripping on my 08 after the installation of the Belanger header exhaust system. I have checked the entire system over many times for leaks, pinched or overheated wires ect. These two codes keep coming back. PO 420 "Catalyst Efficency below threshold" Bank 1, Bank 2. Can my stock ECU be recalibrated to stop the Check Engine Light from appearing? I know of others have this exact proplem.

The system is doing exactly what it is supposed to do since you have changed your catalysts to a different type of exhaust! The Mopar Controller should elininate this issue for you.

 

[SRT Engineers]

viperbilliam asked: "How different is the exhaust system from Gen III to Gen IV? They appear to be very similar. The only difference I know of is the air gap header. Mufflers, cats, and diameter sizes the same? If so, how do you keep the resonance down without the crossovers?"

The exhaust system is similar. The tube in shell (air gap) headers are a significant change. The crossover was removed, improving (reducing) backpressure and some rear bias weight. The exhaust noise, however, did increase slightly but still slithered in under the government restriction limits. Lots of additional tests and tweaks (remember we can adjust our valve timing and incidentally exhaust note / idle stability with the CamInCam) allowed SRT to bring the system to production. KCC

 

[SRT Engineers]

Martin asked:
Q: 3) "I read in the 2010 Chrysler Information pack that the new Vipers have a different 5th gear ratio. In the info pack, they indicated 2009 Vipers have a 0.80:1 fifth ratio as opposed to the previous 0.74:1 ratio. Is that correct and does it only affect the 2009 cars - or all Gen IV cars?"

A: The 5th gear ratio has always been 0.741 for Gen3 and Gen4.

 

[99 R/T 10]

What changes were made to the 08 suspension as compared to the 06 suspension with the elimination of the run flats?

I am curious too.

 

[SRT Engineers]

Bobpantax asked: "1. Hi. It's great to see that Fiat appreciates the value and importance of the SRT team.

We couldn't agree more...

2. I know that you cannot write about future product but can you comment on whether the Ferrari drivetrain engineers and the SRT equivalent are allowed to talk to each other? Is Mr. Winkles occasionally eating some pasta these days?

Winkles likes pasta well enough... but it has nothing to do with Italy in the way you infer.

3. Did you notice that Underground Racing has successfully TT'd a Gen IV with the VVT and Venom programming intact? Yes. They used a Motec controller also but quite an accomplishment - yes? With all of the supercharged Vipers running around with the stock Paxton system with a few program tweaks from D.C. Performance - some of them for well over 20,000 miles of trouble free, relaible driving, has any more thought been given to using a supercharger on the Viper or at least offering it as a factory option?

Sure did... anything is possible with a suitable application of cash. The motec is a very flexible platform indeed. We used an eariler version for the GTSR program. We think about power adders all the time... (even in our sleep sometimes)

4. Why don't you offer the ACR brakes as an option on the non ACR car?

We did on the VOI X edition vipers...

 

[SRT Engineers]

I'm having a problem with the CEL tripping on my 08 after the installation of the Belanger header exhaust system. I have checked the entire system over many times for leaks, pinched or overheated wires ect. These two codes keep coming back. PO 420 "Catalyst Efficency below threshold" Bank 1, Bank 2. Can my stock ECU be recalibrated to stop the Check Engine Light from appearing? I know of others have this exact proplem.

This would be a perfect application for the Mopar Controller. It was purpose built around head applications.

 

[SRT Engineers]

Chelseasnake asked: 1) "hi guys, keep up the good work my question is what is the break down of cars that came to canada for 08 @09 so far? i know of 08 production # in total, but not of us in canada.i know of 4 coupes for sure,2 08 and 2 09 as they are in my garage. thanks CANADA EH"

A: Sorry we don't have the data broken down for Canada. We definitely appreciate our brothers to the north. There are some passionate gearheads up there!

2) "Hi Guys What About The Problem With Some 09 Cars. Seems To Be A Noise From The Power Steering Pump When You Go Around Right Hand Corners Hard?"

A: Make sure your steering fluid level is at the appropriate level.

 

[SRT Engineers]

What changes were made to the 08 suspension as compared to the 06 suspension with the elimination of the run flats?

The entire suspension was retuned for the new tires (springs and dampers). Alignment specs. also changed.

 

[SRT Engineers]

ViperTony asked: "Recently the original water pump failed on my 2001 RT/10 with 16K miles. Thanks to Chuck Tator, I replaced it with an OEM. Was there an issue with water pumps on Vipers whereby the impeller stopped spinning at high RPMs and eventually stopped spinning altogether? If there was an issue, was it related only to 2001 Vipers? Thanks."

A: This is a pretty rare issue. If you've replaced the water pump it should be a good fix. There was nothing particular about the 2001 cars.

 

[ViperGeorge]

Several 08 owners have had hydraulic problems with the clutch. They had to be bled. My Viper Tech said that a factory tech told him to use Dot 4 fluid instead of the Dot 3 indicated on the cap. What is currently used in the Gen 4 and has the cause of the problem been fixed at the factory?

 

[Westxsrt10]

Chelseasnake asked: 1) "hi guys, keep up the good work my question is what is the break down of cars that came to canada for 08 @09 so far? i know of 08 production # in total, but not of us in canada.i know of 4 coupes for sure,2 08 and 2 09 as they are in my garage. thanks CANADA EH"

A: Sorry we don't have the data broken down for Canada. We definitely appreciate our brothers to the north. There are some passionate gearheads up there!

2) "Hi Guys What About The Problem With Some 09 Cars. Seems To Be A Noise From The Power Steering Pump When You Go Around Right Hand Corners Hard?"

A: Make sure your steering fluid level is at the appropriate level.

My 08 makes this same noise when turning sharply to the right. I have my power steering fluid at mid level between low and Max to avoid boil over. So its ok to run the level up to the top line?

 

[SRT Engineers]

Nader asked: 1) "I have just started doing some research on reaching 580 to 600 rwhp in my 04 Mamba. I want to stay naturally aspirated so I know high flow heads and custom cam with a small bump in compression should get me there. Do you have any recommedations on cam size or compression? Also any thing i should look for and stay away from?

2) My other concern is tuning the car. I have the new sct tuner and hardware so I figure I can get it tuned and run a few different tunes depending on the temp or weather. My question is what are the boundaries of the computer in my 04? She someone be able to tune the car safely and still maintain drivability?

I know these questions should also be asked to the tuners out there but I wanted to see what your opinions are first."

Hmmm. This is why we developed the Gen IV engine package. It has all the things (plus some) that you mentioned. With some tweaks it could do what you are looking for (Blatent ad for you to buy a new car) Seriously what you are asking can be done but it will take a lot of effort and significant funds to get there with your hardware/software without pressure or nitrous. KCC

 

[eucharistos]

Everyone on the team left Germany believing we could be running in the teens if we had more track time. If we had a week of 2-4 hours per day (and lots of fresh tires) the ACR could probably run in the mid to low teens, weather and conditions permitting.

made me giddy like a school girl

keep up the good work

 

[SRT Engineers]

ACRsnake asked:

4) Is there a way to change the air filter to a better flowing unit (Mopar ??)?

A: The stock air filter has a very high flow rate. There aren't any Mopar filters available. We don't think you'll realize any hp gians from a different filter.

6) 0W-40 oil is not available here , can i use 5W-40 instead?"

A: 5W-40 should be OK

 

[SRT Engineers]

Bobpantax asked:

5. You have a regular Viper and the ACR road course Viper. Why don't you have a drag strip version of the Viper? It seems like you could make the necessary changes - ability to sit and squat, diff strength, rear end ratio, half shaft tolerance, tranny linkage and a somewhat different tune without too much effort.

A: That sounds like a future product question. : )

 

[Venom08]

I recently had the seats, center console, etc. out of my 08 Viper. I was doing a small stereo install. Anyway, I did not disconnect the battery before I unplugged the seats and removed them, nor when I plugged them back in. I now have a airbag light that stays on when the car is cranked. It goes off after a few seconds upon start up, then comes on with a single chime. Then it stays on. I have tried to unhook the battery and let it sit for awhile hoping to "reset" things...no such luck. I am thinking that there is some kind of code that may need to be reset. I have double checked everything and all is the way it was. Is there a way to reset this light without going to the dealer? I did turn the switch to the ON position with the seats out as well while I was verifying that I had the window switches plugged in correctly (left and right) Could this have been when it threw a code? Thanks for any help.....

 

[JonB]

One of our CO members dispatched a deer this week.....gutted the jumping deer with the ACR wing.
The wing tore off and the decklid / glass destroyed. My question is this:

If PETA sues him, does the Dodge Warranty cover his legal bills since this wing is WILD but not wildlife break-away safe?!


>> Never mind... a LEGAL, not an engineering question?!

 

[SRT Engineers]

Bobpantax asked: "1. Hi. It's great to see that Fiat appreciates the value and importance of the SRT team.

We couldn't agree more...

2. I know that you cannot write about future product but can you comment on whether the Ferrari drivetrain engineers and the SRT equivalent are allowed to talk to each other? Is Mr. Winkles occasionally eating some pasta these days?

Winkles likes pasta well enough... but it has nothing to do with Italy in the way you infer.

3. Did you notice that Underground Racing has successfully TT'd a Gen IV with the VVT and Venom programming intact? Yes. They used a Motec controller also but quite an accomplishment - yes? With all of the supercharged Vipers running around with the stock Paxton system with a few program tweaks from D.C. Performance - some of them for well over 20,000 miles of trouble free, relaible driving, has any more thought been given to using a supercharger on the Viper or at least offering it as a factory option?

Sure did... anything is possible with a suitable application of cash. The motec is a very flexible platform indeed. We used an eariler version for the GTSR program. We think about power adders all the time... (even in our sleep sometimes)

4. Why don't you offer the ACR brakes as an option on the non ACR car?

We did on the VOI X edition vipers...

By the way, you can get the ACR rotors from Mopar:

P5155125 Rotors, Brake, Front Set, Two Piece Slotted Design, 2003-08 Viper
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P5155126 Rotors, Brake, Rear Set, Two Piece Slotted Design, 2003-08 Viper[FONT=ArialNarrow,Bold][FONT=ArialNarrow,Bold]​

[/FONT][/FONT]

 

[SRT Engineers]

Several 08 owners have had hydraulic problems with the clutch. They had to be bled. My Viper Tech said that a factory tech told him to use Dot 4 fluid instead of the Dot 3 indicated on the cap. What is currently used in the Gen 4 and has the cause of the problem been fixed at the factory?

Re-bleeding the clutch line is the first thing I'd look at if you are having issues with clutch actuation. And Dot 4 can help for high temperature usage.

 

[SRT Engineers]

OppositeLock asked: "I own a stock, street driven '09 roadster with 1k miles and have several questions:

(3) For a moment ignoring emissions regulations, where is the biggest compromise in the Gen IV engine (intake, exhaust, materials or tuning) and would that be your first item to change/modify for additional HP and TQ in an off road only environment?

A set of headers and the Mopar PCM would be the trick starting point.

(4) Which parameters does the Gen IV engine's ECU retain when it is disconected (i.e. fuel trims, etc)? And for how long?

All of them and "forever"... the data is stored in flash memory not in volatile memory as in the past. The adaptive adjust every trip, and adjust more rapidly if large differences are detected or the fuel tank has been recently re-filled.

 

[SRT Engineers]

#10 OF 50 asked: 1) "Any way to make more head room in the SRT-C? I need more than 2" to be able to wear a helmet! I would buy a new car, if it could be modified so I fit. What are your recommendations??

A: We can't officially recommend anything, but many taller customers use an aftermarket seat lowering kit to gain more headroom. The reason we can't officially recommend this is because we haven't tested this configuration to the government regulations.

2) Can you make some comments on SRT as a business? Is "SRT", with its multiple products, making enough money to stay in business and design future products?
Is there a "business case" for SRT to continue? Does SRT have any brand recognition?
(and I'm not suggesting SRT take off the Viper name like the MX-5 ditched the "Miata")

A: We are all proud to work at SRT and we feel that SRT makes a great contribution to the company. Sorry we can't comment on future product or profitablility. As far as brand recognition goes, SRT is growing as a respected brand among car enthusiasts. You guys in Viper Nation have played an important role in spreading the word. Thanks to all of you!

 

[SRT Engineers]

Lastly, please confirm the latest and greatest SRT oil filter part number for the Gen IV motors....there seems to be a lot of confusion on this. My owners manual says one part number and aftermarket suppliers of SRT filters list another

Gen III and earlier version of the SRT oil filter 05037836
Gen IV and beyond SRT oil filter 05038041

Moderator edit. Gen 4 part number corrected to later SRT Engineer statement.

 

[Y2K5SRT]

Bobpantax asked:

5. You have a regular Viper and the ACR road course Viper. Why don't you have a drag strip version of the Viper? It seems like you could make the necessary changes - ability to sit and squat, diff strength, rear end ratio, half shaft tolerance, tranny linkage and a somewhat different tune without too much effort.

A: That sounds like a future product question. : )

We will take Bob out behind the shed and beat him later.

 

[JonB]

..(4) Which parameters does the Gen IV engine's ECU retain when it is disconected (i.e. fuel trims, etc)? And for how long?

All of them and "forever"... the data is stored in flash memory not in volatile memory as in the past. The adaptive adjust every trip, and adjust more rapidly if large differences are detected or the fuel tank has been recently re-filled.

Fuel Tank Filled? As with 91 vs 93 octane? Or Empty vs Full? Why would the adaptive react more quickly after a fillup? If a guy wants to drag race, besides the "Empty tank" weight advantage, what is the PCM looking for and adjusting for with a full tank ?!?!

 

[99 R/T 10]

The entire suspension was retuned for the new tires (springs and dampers). Alignment specs. also changed.

So it begs the question, if the 2003-2006 guys get rid of their runflats(no longer available), how can they tune their suspension for optimal performance that matches the 08/09 Vipers?

 

[ViperGeorge]

So it begs the question, if the 2003-2006 guys get rid of their runflats(no longer available), how can they tune their suspension for optimal performance that matches the 08/09 Vipers?

Precisely the point of my original question. Thanks for clarifying it.

 

[SRT Engineers]

Bobpantax asked:

6. It's a bit off topic but how much tolerance is there in the Jeep SRT 8 stock tranny? Will it take another 100HP without a problem or is it too fragile for same?"

The a580 trans in the Jeep SRT-8 is has a torque limiter on it to protect from peak torques in 1st gear. From our experience the limits placed on the trans are quite conservative. Hard to say how long and it would last with an extra 100 HP, but it's probably a question of when, not if it will go.