June 14, 2006 SRT Engineering Thread

Discussion in 'SRT Engineering Q/A' started by Jay Herbert, Jun 11, 2006.

  1. Jay Herbert

    Jay Herbert Enthusiast

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    A group of SRT Engineers will be monitoring (only) this thread on Wednesday, June 14, 2006, from 6:00 p.m. EDT–8:00 p.m. EDT. They will answer any* questions posted here during that time. You can even carry on a live discussion with the SRT Engineers by posting back and forth during this time period!

    A few more details

    1) This forum will be open for posting questions during the time period stated above, about thirty SRT Engineers will be answering the questions, so start thinking up those questions now.....

    2) Post all Questions WITHIN THIS THREAD. Questions posted individually/outside of this thread will not be answered.

    3) ONE, 1, uno, question per post please

    4) *SRT will not answer any questions "pertaining to future product". Please respect this, and understand it is corporate policy.

    5) Enjoy.

    This forum/thread will be opened for posting just before 6.
     
  2. Jay Herbert

    Jay Herbert Enthusiast

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    A special thanks to SRT Engineering and the VCA National officers for making this discussion possible. Enjoy.
     
  3. JonB

    JonB Viper Owner

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    1) Please consider swapping the Left-Right SRT10 E-brake actuators, so that they are not aligned "elbows out."
    In this way, a wider array of aftermarket (lighter) wheels can be chosen.

    2) I prefer the water temp gauge at the TOP of the gauge stack, not 3rd down. What decided ?

    3) Howcum 'oil starvation' is still an on-track issue with Gen-111, as with some Gen 11? Can't you design this oil pickup issue away?

    4) TV, SVE, PVO (you guys!) led the way with the GTS-ACR and Ride Heighth Adjustability. The Z-06 nor almost nothing else has it. Please bring it back when you think of future products you cannot discuss here....

    THANKS for being here..See you at VOI! Jon Brobst

    Hi Jon.....
    1...we can look at that but we may find that there is hidden costs involved.

    2...we felt the most important gauge was oil pressure because that indicates the health of the motor.

    3....we are working on making the swinging pickup available through Performance parts

    4....we will not lose sight of the adjustibility
     
  4. Yellow32

    Yellow32 Viper Owner

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    Are there factory-sanctioned assemblies to change the

    Coupe's exhaust from the side pods to the rear? And, if

    so, are there 'new' side pods available that do not have

    the exhaust tip outlet?
    ===================
    Any ideas on how to make the gauges more useful when

    tracking the car? The vertical placement is beautiful but

    is hardly useful when tracking as I have to either move my

    right hand/arm off the steering wheel or move my head over

    to read the gauges. And, when tracking the car I have

    found it best to not remove my hand from the wheel (even

    on straights which is where I have to do my checks now)

    By 'ideas' I mean is there an optional way to arrange the

    gauges, maybe an alternate dash board. The three guages I

    care most about are the coolant & oil temps and oil

    pressure.

    ====================

    Will blueprinting the transmission really make shifting

    that much easier? And if so, whom do you recommend to

    blueprint it? (is this something Arrow does?)

    ====================

    What engine modifications can be done to give the engine

    the most power without resulting to forced induction or

    turbos? Blueprinting? new lifters? new manifold? Oh, and

    keep the car OBD2 compliant.

    ====================

    Would be nice if you could order the Quaife Differential,

    Moton Shocks and Baffled Oil Pan w/Swing pickup directly

    from the factory - I would like to see these options (or

    all together as an option package) on future Vipers.

    ====================

    Can you tell me if any Red and Black Stripe Coupes were

    produced for 06 (or are scheduled to be produced)

    ====================

    Lastly, on all the Coupes I have seen so far there is a

    defect in the rear glass that causes a distortion when

    viewing out the rear-view mirror (the glass is imperfect),

    has this been corrected, if not, will be addressed for

    future production?


    Thank you!

    John



    Let's see which questions I can help you with:
    - no plans for rear exhaust
    - no gauge ideas for you
    - Quaif, Motons, swinging oil pickup would make a very nice package...
    - Red with black stripes was available for order, but as we are still in production I can't tell you how many are going to be built - I think these will be pretty rare, especially with H-spokes
    - We are continously reviewing any quality issues and the glass issue is definitely on out radar screen
     
  5. SRT Engineers

    SRT Engineers SRT Engineers

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    Thank you also to the VCA for giving us this great opportunity. And we're open for business.
     
  6. MoparMan

    MoparMan Enthusiast

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    Regarding my '00 GTS with Belanger headers, no cats, SIM box for cat deletion, MP exhaust, smooth tubes, K&Ns.

    1) After the addition of the headers and the deletion of the cats the car is running rich. A scan of the PCM shows no errors, is it likely that the deletion of the cats is causing the rich condition or is there another cause?

    2) In regards to correcting the rich condition I'm considering either a VEC2 or a DC Performance reflash of the PCM. Do you have any opinions regarding either option?


    The Mopar upgrade is designed for '03-'05's. We really can't offer you any help with your set-up.
     
  7. MoparMan

    MoparMan Enthusiast

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    Also, please consider adding simple mods that most of us do right away to the production car such as a short throw shifter, K&Ns, etc. An option for a Quaife in the rear end would be cool, too.


    Thanks for the suggestions. We work closely with Mopar Performance Parts and we'll add this to our list of "wants" from you guys.
     
  8. GR8_ASP

    GR8_ASP Enthusiast

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    Any thought or work to make a high temp / track compatible ABS sensor?
    In all of our track experience with the Viper we have never had a temperature related problem with the sensor - how are you using the car.
     
  9. Jay Herbert

    Jay Herbert Enthusiast

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    This was asked elsewhere, but fits here well:

    1) Is the Comp Coupe Transmission the same as the stock SRT-10 Transmission?

    2) Have you ever tested any Modified T56's, like that which Rockland Standard Gear offers (rated at up to 1200 hp and 1000 lb-ft of torque)?


    understand you may not be able to answer (2)

    Jay old buddy,
    No and No
    The Comp Coupe trans is different as it has a cooler potential, 1-2 shift block out with the electronics, short shift package, and vespal shift fork pads. The Lemans Trans updates have been included in the latest production transmissions and will see additional upgrades down the road.
     
  10. MoparMan

    MoparMan Enthusiast

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    How much weight would be saved by changing from late gen 2 rims to the new five spoke SRT rims?
     
  11. GR8_ASP

    GR8_ASP Enthusiast

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    When ABS is in default what is the front to rear brake bias? Can it be adjusted to provide reasonable brake performance?


    The ABS system has no pressure bias via a prop valve or similar device. Full pressure goes to the rears and the EBD (electronic brake distribution) algorythms control the amount of rear brake. The system is tuned to give a <100ft stopping distance from 60 mph and maximizes the capability of the monster rear tires. The system is tuned for the production chassis setup.
     
  12. a-mechanic

    a-mechanic Viper Owner

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    Has anything been discovered as to why cat convertors are dying and then killing motors(overheating one side and seizing the rings) on the 04-05 models? I put it this way because it has been my experience cats don't die they are murdered, and if so what is the fix/problem?
    thanks

    I'm assured that no animals were harmed during testing of the Viper...
     
  13. 418viper

    418viper Enthusiast

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    Thanks for the support, several questions
    1) Is the cure for the oil starvation under heavy cornering to install the performance oil pan and pick up, or as some have mentioned on this site to drill holes in the pan baffles to allow drainback?

    2) Will changing the swaybar bushings to polyurethane make an improvement in cornering performance?

    3) When will the loose crank puller issue be resolved? Should we all loctite in the meantime?

    4) Please install a trunk release button inside the cabin.

    5) On the gen3 heads on the intake port floor just before the short side radius there is a depression. Is this to reduce fuel puddling???

    6) What is the minimum piston to valve interference (looking to install larger intake valves)?
    Thanks!!!

    On question 4 FYI the trunk release on the key fob will work with the ignition on if the car is stopped and the park brake is engaged.

    On question 6, our recommendation would not to go below 2 mm but 2.5 mm would be safer.
     
  14. Lee00blacksilverGTS

    Lee00blacksilverGTS Viper Owner

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    How does the weight of the new 2006 5 spoke wheel compare to the sidewinder/copperhead wheel?
     
  15. Jay Herbert

    Jay Herbert Enthusiast

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    Also, is the new 5 spoke stronger as the spokes go all the way to the edge of the rim?
     
  16. 2002_Viper_GTS_ACR

    2002_Viper_GTS_ACR Viper Owner

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    1. What is the difference between an srt-10 differential and a comp coupe differtial

    2. Early diffs were more prone to breaking, what did you guys do to beef them up, and what year did that happen, and was anything done differently for the 06 model year?

    3. Did the 2006 srt-10 Coupes get stiffer shocks or springs vs the srt-10 convertibles?

    4. What are the weights of the 4 different types of srt-10 wheels

    5. Any suspension changes for the 2006 srt-10 coupe over the srt-10 convertible, like sway bars, or any other type of suspension related change, or alignment difference?

    6. How much more rigid is the 2006 srt-10 coupe over the srt-10 convertible?

    7. What additional changes did the 2006 srt-10 coupe get, other then a hard top and subsiquent rear deck changes, anything in the interior, in the motor, in the driveline, etc?

    8. 04 (i believe) at least 05 srt-10 and later vipers have knock sensors, are they actually being used, what is their purpose? Will they back out timing if knock is present?

    9. from 03 to 06 srt-10/srt-10 coupes do the computers have any timing changes or fuel curve changes?

    10. How much hp or tq can a srt-10 stock tranny, diffential, 1/2 shafts and clutch take before being at risk for breakage?

    11. I dont suppose you guys have a clue on total production numbers for srt-10 coupes yet, ball park?

    Question 1 The Comp Coupe LSD Diff is a fairly expensive Ricardo race part very similar to what went to Lemans. The production unit uses clutch packs with an intergral pump which help to clamp the discs.

    Question 2 We continually upgrade components as the engine power increases.
    Metalurgy of selected components has been upgrade over the last few years.

    Question 10 Now you have to define what year the stock parts are from. If you believe a certain John from TEXAS, the driveline is bullit proof up to 800 HP although we would not agree. We apply the necessary upgrades when we raise up the power but cannot test with all the mods that our customers cleverly add on.

    Question 8 Knock sensors pull out spark and then add a small amout of fuel under high temperature conditions.





    Jon
     
  17. SRT Engineers

    SRT Engineers SRT Engineers

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    Thanks for the suggestions. We work closely with Mopar Performance Parts so we'll pass these along.
     
  18. SRT Engineers

    SRT Engineers SRT Engineers

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    The Sidewinder wheels save approximately 28 lbs per vehicle over the 2006 production 5 spoke wheels.
     
  19. SRT Engineers

    SRT Engineers SRT Engineers

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    Typically, a heavier wheel is tougher than a lighter wheel. However, the Sidewinder wheel passes all SAE standards.
     
  20. SRT Engineers

    SRT Engineers SRT Engineers

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    The knock sensors were added at the same time the Rams were launched to protect the engine from lo-octane fuel usage, especially while towing. The viper gained the sensors as the work had been completed for the Ram. The sensor will adjust timing if spark knock is present.
     
  21. Kai SRT10

    Kai SRT10 Viper Owner

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    How many tires can the stock tire pressure monitor system keep in memory?

    The system will only support four tires.
     
  22. DavidSB

    DavidSB Viper Owner

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    Great for you to join us for feedback.
    This is my first Viper and, while I love it (and track it often), below are a few issues that your group may be able to address:
    1. Rollover protection - an $80,000 500+ HP car should have real rollover protection. Even a basic Boxter has it. The lawn-furniture-quality aluminum roll hoops instill a false sense of security for many, nothwithstanding the warniing labels.
    2. One shouldn't have to change to a Comp Coupe oil pan to prevent oil starvation in high G turns.
    3. Many owners change out the shifter and shorten the shaft. I've seen - and just barely avoided - a missed 4th to 3rd shift into 1st. At best you flaten tires and more likely you'll loose control of the car and possibly overrev the engine. There are some simple fixes, such as the DC Performance shifter with a spring tensioning bolt, but the OEM shifter should give a more precise feel with a shorter shaft.
    4. And finally, don't loose sight of William Stout's famous dictum: “Simplicate, and add more lightness”.
    Thanks for all you work in making such a great car.


    1....lawn furniture should have such good aluminum.......

    2....we agree

    3....when you shorten the shaft, the efforts go up which can hurt the precise feel

    4...we are always looking for ways to go lighter....and we definitely like simple
     
  23. SRT Engineers

    SRT Engineers SRT Engineers

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    *DELETED*
     
  24. MoparMan

    MoparMan Enthusiast

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    Marko (Nev region pres) has the following suggestion for you: consider two piece rotors for the next Viper.

    Also, with Dan now at Mopar, give some thought to stage I/II/III type kits for the Viper, including the gen I and gen II cars.


    Dan? Dan who? It doesn't take long to forget us ........
     
  25. 2002_Viper_GTS_ACR

    2002_Viper_GTS_ACR Viper Owner

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    AWESOME !! so the computer must have been updated to work with the Knock sensors then in the later years right? I dont suppose you guys decided to get more agressive with timing, since knock sensors could be a great safety blanket.

    No the spark timing did not move... The 03-06's all run the same spark timing.
     
  26. SRT Engineers

    SRT Engineers SRT Engineers

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    only four.....
     
  27. Kai SRT10

    Kai SRT10 Viper Owner

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    I suppose you folks can see how this could be a problem for those who like to track their cars.

    The system will let you run five ignition cycles with no sensors present before is sets a fault. This was done to support you track guys. The key is no sensors. If it sees only one or two sensors your going to get a warning.
     
  28. 418viper

    418viper Enthusiast

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    If the tire pressure monitor senses low pressure is the engine horsepower then reduced?
     
  29. Kai SRT10

    Kai SRT10 Viper Owner

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    Here is an exerpt from a letter I wrote a while back to Mr. Helbig regarding my desires for the next generation Viper. You've probably heard all of these suggestions from other people, but I am going to repeat them again. Please keep them in mind when you are busy designing the next Snake.

    #1: Improved Oiling
    The Viper’s oiling system needs to be re-engineered. At my last open track day, my car lost the #3 rod bearing due to oil starvation. The rod shattered, the piston was smashed, and the cylinder sleeve damaged. This is not an isolated incident. Dozens of Viper owners have had similar issues with their cars when driving them on the track. I had even taken the precaution of installing an aftermarket “Comp Coupe” swing arm pan to help with oil pick up under high g-forces. Unfortunately, the design of the oil galleys is such that the #3 bearing is particularly susceptible to oil starvation, and the CC oil pan alone was not enough. I’m having my engine re-built, with coated bearings, forged internals, and am adding a 3 quart accusump auxiliary oiler to try and address this issue. This is both expensive and frustrating. I really believe that a Viper should be track worthy straight from the showroom floor. I don’t expect to be able to run the 24 hours of Lemans with a street car. However, I should be able to run my car at the occasional open track day and time trial without having to go out and buy aftermarket oil pans and accusumps. I shouldn’t have to worry about spun rod bearings and broken pistons. The oiling system is the weak link on this otherwise “bullet proof” engine.

    In your design of the new engine, improving the oiling system should be your top priority. Ideally, you should design the new car with a dry sump system. If the car is going to be taken to the track, a dry sump is the only way to ensure that the components get adequate oil 100 percent of the time. A dry sump will provide for increased reliability on the track, and will increase power as well. A serious sports car needs a dry sump. Without improved oiling, the new Viper will not be track worthy.

    #2: A better Differential

    The stock Viper differential has a couple of serious drawbacks. The spider gears are prone to failure, and when on the track, the dif tends to spin the inside wheel, (followed by a sudden lock) during fast tight turns. I replaced my stock differential with a Quaife torque biasing differential after about a year of owning the car. I was amazed at the difference that the Quaife differential made in the handling of the car. High speed corners were much smoother, and I could get power down on corner exits much sooner with the Quaife. Inside wheel spin was eliminated, and I also got rid of the unsettling mid corner “lock-hop” that the stock dif is prone to. Vipers have traditionally had a bad rap when it comes to snap oversteer. A good alignment and addition of a Quaife have made my Viper much more predictable and controllable on the track.


    #3: A real roll bar

    Get rid of the silly “sport hoops.” If you are going to sell a convertible with no stability control, over 500 ft-lbs of torque, and speedometer that goes to 220mph, you really need to equip it with a functional roll bar. This goes for both street and track. A real roll bar would make the car safer on the street, and would allow the car to drive at open track events without installation of an aftermarket bar. You can keep all the liability limiting warning stickers about how the Viper is an open car. Just give us some real roll protection.

    #4: Tire pressure monitor system that can handle multiple sets of tires.

    I’ve got two sets of track wheels/tires, a set of stock wheels/tires, and two drag wheels/tires. The stock tire pressure monitor system on my 2004 can’t handle this many wheels/tires. Please install a system on the new Viper that can handle multiple wheels/tires without requiring trips to the dealer to program the tire sensor control module.


    1.....we continue to look at ways to improve the reliability...the engine is the heart of the car

    2....the diff is also on our radar screen for improvements

    3.....we have too many lawyers to discuss roll bars

    4.....this is complicated because the system has to recognize different sets or combinations of sets of wheel/tire assemblies nothing on the horizon...

    Question 1/2 We have been running upgraded components in World Challange and Track Days with with very positive results. I can also tell you the production cars unmodified have seen thousand of track miles with good durability. We have also had guest World Challange drivers at our development track events with these products with very positive comments. Stay Tuned.
     
  30. SRT Engineers

    SRT Engineers SRT Engineers

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    No but it does give two stages of warning, first at ~20 psi, and then louder and more annoying at ~14 psi. Power is not effected, you should however consider decelerating on your own.
     

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