Welcome to the RACER Mailbag. Questions for any RACER contributor can be sent to mailbag@racer.com. We love to hear your comments and opinions, but letters that include a question are more likely to be published. Questions received after 3:00 PM ET each Monday will appear the following week.
Q: I have been following competitions of all kinds all my life. I kind of miss the unknown possibilities of a blown engine during a race affecting the outcome with these near armored engines (unless it was someone I was rooting for).
I’m looking forward to another fun weekend with the IndyCar circus and other fans at Mid-Ohio, and I wonder what (if any) problems the new hybrid powertrain systems create? What could go wrong with them that could cause some sort of engine failure?
Mike Nikishin, Burgettstown, PA
MARSHALL PRUETT: We’ll have to run the first hybrid race to get a better idea of the problems that might arise. Thousands and thousands of test miles have been covered, but we’ve never gone a full race distance with 27 cars and with car contact and all the other normal things that happen and get confused between the green and checkered flags that can shake and rattle the ERS .
We may have an ESS or MGU failure. An ESS problem isn’t necessarily the end of the world, but a stuck or broken MGU, as it connects to the engine’s crankshaft via the input shaft, can cause a hem. Overheating of the ERS module — ESS or MGU (or both) — can cause damage.
The MGU is the main susceptibility zone at the beginning of hybridization. There’s nothing wrong with that, but IndyCar doesn’t want to push it too hard, so the power figures are kept a little low. When IMSA went hybrid, there was an expectation of all sorts of ERS issues, but it never became a serious problem. There were occasional hiccups, but nothing widespread.
Some final words for me here, but the IndyCar final spec ERS has done a lot of work and reliability has been pretty good, so based on that reality I would expect Mid-Ohio to continue the trend. Put another way, it would be a surprise if all the reliability we’ve seen with the final-spec ERS goes out the window, leaving half or more of the field parked and smoking on the side of the road Sunday.
Q: I realize charters are a foregone conclusion at this point in IndyCar, but I just don’t understand why the series is so adamant about adding them? I totally understand why teams want them, but it doesn’t make a lot of sense to me from a series perspective — it’s not like it’s struggling to attract car owners and interested teams right now. Why go through all this trouble, turn away potential interested parties and reward charters to incumbent teams? Now they don’t have charters and these same teams show up every week and there’s a full network. If this was 2007 I could see how charters would have value to the series at a time when it was hard to get a full grid every week, but are they really worried that a bunch of teams will up and leave now without a charter system?
I’d rather the series take the opposite stance and lean into the competition — embrace the hustle! You can run a road and street course, qualifying with Round 1 split into three groups — the top two from each group automatically advance to the Fast 6. The bottom two or three from each group go into last-chance qualifying like Indy for the final spots on a network that would take the place of the now-controversial Fast 12 segment. That would certainly make qualifying even more exciting and force teams to up their game if they want to keep playing — which can only be good for the product, considering this is a pro series.
Matt, Nazareth, PA
MP: I’ve had the same struggles to find the overwhelming reasons to create charters, but we know that team owners would like their records protected so that starting positions are guaranteed in every race – except, thankfully, the Indy 500 , which they pulled after receiving a lot of backlash from fans — is something they’re going to get.
And adding free market monetary value to their records is another thing they won’t turn down, so that’s what they’ll get too. This all fits in with the spec-oriented direction the series has been going for many years. Eliminate as many areas of potential failure as possible, such as multiple tire suppliers and multiple chassis suppliers, so that no one is at risk of choosing the wrong supplier and thus it is almost guaranteed that you can compete at the highest level.
It also protects your ability to compete in all but one race, while allowing newcomers to be the only ones at risk of failure and possibly going out of business. This is not the racing spirit I fell in love with.
Without the guaranteed starting positions, the charter works for me, but maybe I’m looking at it the wrong way.
Charters bring obvious benefits to teams, but perhaps at the cost of competition. Phillip Abbott/Motorsport Images
Q: As an engineer, I have no problem switching between US and metric units to make comparisons. However, many fans on social media are completely confused by IndyCar’s insistence on using the long-standing US power and torque units for the ICE, but metric for the ERS. Frankly, I think this is a deliberate deception to cover up how underpowered this ERS is in practice compared to everything that was promised.
Power is torque times rpm plus any necessary conversion factors. 30Nm of torque at 12,000rpm is equivalent to just under 51bhp, an awful lot short of what the originally stated targets were to begin with.
The series will allow 105 kJ of energy expenditure per lap in Iowa. This is equivalent to 50 hp. in 2.8 seconds, assuming the driver is able to pack and deploy that much with everything else going on during an 18-second lap — and a 100% efficient MGU, which we know isn’t possible.
The capacity of a standard rechargeable lithium battery on an owner-level weed killer is 30 watts. One Wh equals 3.6 kJ, so this pack contains 108 kJ of energy. Obviously, I don’t expect Hinch to make that comparison on screen, even though it’s realistic.
A gallon of E85 contains about 94,000 kJ of heat energy, and a turbo engine at full throttle can achieve 40% efficiency in converting heat energy to kinetic energy on the drive shaft. 105 kJ is only about as much energy as the ICE puts out the back end from burning 0.14 ounces of E85.
I’m a fan of the Turbine Age series and I’m really having a hard time understanding the hype surrounding this “development”. It’s a mass of complications with precious little benefit compared to allowing a bit more turbo boost, OEM marketing efforts be damned.
Steve Jarzombek
MP: I hear you, but there are a lot of limitations that IndyCar has placed on itself by sticking to the same chassis because there was no room to build a robust high-voltage lithium-ion battery solution. Left with a small gap to fill the bell, what Chevy and Honda have come up with is, as I’ve said many times, a miracle in a package. But due to the extreme limitation of space to put ESS and MGU, they were not able to make a monstrous ERS that delivers gigantic horsepower and torque.
The series says it can go up to 150 hp. with the unit one day so that would be great. But it starts at a modest 60 hp. and 33.2 lb-ft of torque to maintain the reliability achieved with the MGU.
First and foremost, this is a marketing exercise, not a thorough technological study by IndyCar, Chevy or Honda. The aim is to give its current and hopefully more car brands in the future the relevance they need to stay or join the series. So far, from 2013-23 (and half of 2024), no manufacturer wanted to join IndyCar until it was hybrid.
The new ERS package may not deliver the jaw-dropping performance we were hoping for – at least initially – but I’m focused on what the switch to hybridization can do to attract more car companies to the series.
As for the units of measurement, I expressed the concern and need for the series to Americanize everything related to ERS units. Newton-meters and kilojoules just don’t matter here, so hopefully the advice was taken.
