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Dodge Viper: The Full Story of the World’s First V10 Sports Car (2020 and 2021)

If you have any corrections, additions, or updates, please contact me from the form on my home page. The new softcover version fixes any issues listed here and some which are not!

Reviews for the Viper book

Jim Donnelly wrote: “In 136 hardcover pages, it tells the story of how the odd couple of Bob Lutz and Francois Castaing brainstormed this Cobra revival, and goes through all the engineering studies, which sadly included a stillborn mid-engine prototype. ... we like it because it stands as an easily read model history and a very good quickie reference guide to the wild cars.”

RetroSpeed: “this is a great value, 136-page book, full of colour and written with an obvious passion. It also tells the reader everything he/she needs to know about what we may soon regard as the last real American rebel. I give it five stars, to go with the stripes.”

Classic Car Weekly: “David Zatz is a font of knowledge on the car technically; he's also well-versed in the politics at Chrysler that saw the car built...”

Classic & Sports Car: “a well-rounded and enjoyable book”

Retro Speed: “a great value, 136-page book, full of colour and written with an obvious passion. It also tells the reader everything he/she needs to know about what we may soon regard as the last real American rebel. I give it five stars, to go with the stripes.”

Autoliefhebbers.be wrote: ... “The many color photos and the useful index complete this fantastic book. Just like the Viper, gorgeous! ”

TXGarage wrote: ... “In its 132 pages, Zatz carefully documents the Viper’s development and subsequent offshoots. ... when first revealed, the Viper was still several years from production, and you would have thought the automotive buff books had – collectively – seen the second coming of Jesus.”

AutoWeek wrote: “... with the Viper out of production for a few years now, perhaps it is time to take stock of just what it has achieved for Chrysler, Dodge, and SRT, but without the rose-tinted glasses.”

Try it for yourself

Buy from:

• Bookshop.org
• Amazon •  Revised paperback edition; original hardcover also in stock
• Veloce (direct) (ebook available!)

Updates and corrections from Dick Winkles

Dick Winkles worked on the Viper’s powertrain for 21 years, from early in the project (with a six-year break from Viper from late 1993 to 1999) to near the end, when he retired in 2015. His corrections, in some case, conflict with our original sources, including other members of the Viper team and Chrysler press materials, but over time people remember things differently; and Dick is held in high regard by members of the Viper team and others within Chrysler. 

• The 2013-17 was coded ZD; the 2003-2006 was coded VGX originally, but was later changed to ZB. (This was an embarrassing point to get wrong, and is entirely my—the writer’s—fault.)
• Regarding the engine controllers: I did try to verify the story in the book, but it’s possible the person involved was either not checking very carefully, or did not remember the details.
      In any case, Dick wrote that the early mule cars used two Chrysler Single Board Engine Controller (SBEC) V6 computers, running their own special software; starting in early 1991 development and then, into production from 1992 to 1995, they used a modified SBEC V8 Engine Control Unit (ECU) with unique software and a separate Viper Ignition Control module (VIC). The VIC had all five of the ignition coil drivers while two of the V8 unit's existing coil drivers were re-purposed to run the two additional fuel injectors to supplement the eight existing injector drivers. All of the processing was done by the SBEC, the VIC was simply an output device.
      Coils were indeed borrowed from V6 and in line 4-cylinder engines but with the V10 cylinder numbers molded into the shell making them thereby unique to the V10. 
• Page 39: Dick said the changes were done to improve pass-by noise numbers and sound quality, but primarily so the exhaust back pressure could be reduced, netting more power.
• Page 46: Spark didn't change, but reduced overlap reduced idle combustion instability, which was required to detect idle and light-load misfire.
• Page 51-53: The section is mainly accurate but Dick was at Lamborghini Engineering, not HQ, working for Mauro Forghieri. One of his assignments was to try to reduce Lamborghini’s costs by switching from their pricey Magneti Marelli engine control units (ECUs) to Chrysler SBEC V6 controllers. He got an engine running there, to get the first V10 mule car running (with an iron-block V-10 engine) and the first three prototype cars (with aluminum V10s) until the production-intent control system was ready. He was sent back to Lamborghini for a month in Fall 1990 while the first all-aluminum Viper prototype engines were being measured and assembled as long blocks. The long blocks were shipped back to the United States to be final dressed and tested in Cell 13.
• Page 62:The original intent was to use noise cancellation, but the system couldn't stand up to the heat. The Viper always had four catalysts. The O2 sensors did not have heat issues; the second O2 sensor, downstream of the front catalyst, was needed for the OBD-mandated catalyst efficiency monitor.  The exhaust crossover was a last-minute fix needed to meet pass-by noise requirements, but it created a lot of heat issues. “Everything about the 2003-2006 exhaust system, from the exhaust manifolds to the crossover pipes, was a compromise.”
• Page 75: Piston pins were smaller and lighter, and got a bronze bushing with spiral locks - a full floating pin. With the old pressed in rod pins, there was sometimes scuffing of the piston pin piers and pin bore; this was eliminated with this change.
• Page 76: Dick wrote:
  • “Originally, the Mechadyne system allowed us to vary both the intake and exhaust valve timing . We built three test engines with dual VVT (one of these unique blocks now serves as a 10 bottle wine rack/table in my kitchen—I didn't want to scrap it!).
    Our main goal was to satisfy the EPA/CARB full range misfire detection requirement. We had found that only reducing valve overlap at idle and light load produced stable enough combustion to be able to detect misfire at those conditions. If we had used a traditional fixed cam we would have had to reduce overlap so much that we would have lost 100 hp or more. The VVT was the only viable path for stable idle and light load operation while maintaining top end power.
          This created a huge engineering task. We found through testing that the exhaust timing had the most significant effect on idle stability. Intake timing had a bigger effect off idle and low to mid range torque. We decided to use only the exhaust VVT control; this simplified the calibration workload and we didn’t yet have a reliable "nested" dual VVT phaser.
          Not having the ability to vary the intake valve timing, we positioned the lobe centerline at the optimum position for peak power and locked it there. In doing so, we gave up significant low/mid torque potential - as much as 100 lb-ft at some speeds, but we didn't really need more torque! We really didn’t widen the power band but we were able to maintain and ultimately improve the mid and high range - The VVT strategy did allow us to use more aggressive cam profiles and still maintain good idle and light load combustion. The VVT cam had both longer duration and higher lift than any of the previous Viper cam profiles, which improved power. 
          The emissions and fuel economy effects of VVT were not the primary drivers, misfire detection was. 
• Page 77: “The exhaust used double walled airgap tubular headers to increase flow...”  This is missing some pertinent facts. We had many more “knobs”  to turn with the VVT and ETCs, and used these to meet the pass-by noise requirements.
• Page 77: “new control system, provided by Continental, monitored the crank and cylinder positions up to six times during each spark; the computer, dubbed venom had 10 times as much processing power as the 2007 PCM...”
       The crankshaft position trigger wheel went from 10 position notches for 1992-2006 (one for each cylinder TDC) to 60 (minus two with a 2x wide notch) for 2008-2017. This resulted in crank position a pulses every 6 degrees of crank rotation rather than one pulse every 36 degrees that the older engines used. This provided much more accurate spark delivery but was really necessary in order to achieve full range misfire detection (from idle to redline—a huge undertaking for a large-displacement, odd-firing engine!). Thus, this high data rate and computation complexity (for misfire detection) drove the need for a much more powerful engine control unit microprocessor, a completely new ECU and all new software...all this for high speed misfire detection capability to meet the full range requirement. 
  
• Page 90: “Revised pushrods made it possible to find misfires”...We did stiffen the pushrods to improve valvetrain dynamics, which did improve power slightly, but they really had no effect on misfire detection. 
• Page 90: “They kept the side pipes, but got better exhaust sound via new seals, engine mounts, and bushings...” The catalyst got a new-technology “thinner” washcoat which reduced backpressure and we did much more muffler tuning for sound. The engine and trans mounts were changed from rubber to hydro mounts which reduced the vibration to the frame and thereby the interior.

From Maurice Liang

Maurice Liang, a founding member of both major Viper clubs, has written several books about the Dodge Viper, including one where he was embedded in the development process. He pointed out that the Gen II Viper did not have electric-adjustable pedals; it had mechanically adjusting pedals (the Gen III had electric ones). More corrections are coming.

Do you have other updates, corrections, or additions?

Contact me from the form on my home page.

Also by David Zatz:

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