PRUETT: Time To Untether IMSA's DPis and P2s

Image by LePage/LAT

PRUETT: Time To Untether IMSA's DPis and P2s


PRUETT: Time To Untether IMSA's DPis and P2s


The time has come for IMSA to award separate points for the pro DPi and pro-am LMP2 cars within its Prototype class. It’s also time for IMSA to end the fruitless attempts to make these vastly different styles of prototypes perform at the same level.

Implementing those changes halfway through the 2018 WeatherTech SportsCar Championship isn’t an option, but with 2019 as a reasonable start date, there’s more than enough time to map out a new and happier direction for the Prototype category.

IMSA’s ongoing practice has been to take the fastest P2 chassis and balance the DPi field to match that model’s anticipated performance, and from this policy, immense tension has arisen. Eighteen months in, the efforts to achieve parity on the stopwatch between factory DPis and spec P2s teams have not met expectations, and nor will it without taking drastic measures.

Ask any of the DPi teams, and they’ll tell you the current state of BoP with their cars is well past drastic… Shift over to the P2 contingent, and they’ll tell you that despite reassurances to the contrary, being able to capture overall wins is little more than a dream.

And that’s not a critical jab at IMSA’s technical department. The concept of balancing DPis and P2s was ambitious from the beginning, and as time has shown, it’s only become more difficult as the manufacturers continue to make their DPis faster while the P2s entrants remain moored to a set of spec rules dating back to 2017. DPis move forward, P2s are frozen in place, and the divide widens with each new race.

Through four rounds, DPis have taken 11 of 12 possible podium spots. On Sunday at Mid-Ohio, the best P2 entry came home 1m13.876s behind the winning DPi. It was driven by Sebastian Saavedra and Gustavo Yacaman, two young veterans of open-wheel racing, and in a flat-out race that went caution-free, they were just a few seconds from being lapped when the checkered flag waved.

Image by Galstad/LAT

Nearly one lap behind, it’s all the customer P2s had to offer, and that’s after back-to-back BoP changes designed to stop the runaway DPis. At the previous race in Long Beach, a late caution resulted in a 19-lap sprint to the finish. The best P2 was 19.686s behind the winning DPi when it crossed the line.

We have one style of IMSA prototype having big factory dollars spent in wind tunnels, engine dyno cells, 7-post shaker rigs, and on all the virtual testing money can buy –chassis simulations and aero CFD – while the privateer P2s, run mostly by small business owners, are no match for the cubic dollars and resources on display in the DPi camp.

And despite the frequent BoP alterations, the extra weight, reductions in horsepower and torque, and losses in fuel capacity have not stopped the headlining prototypes from Acura, Cadillac, Mazda, and Nissan from trouncing the customer P2s.

From the 14 WeatherTech SportsCar Championship races held since the start of the DPi/P2 formula in 2017, DPis are 13-1. That’s a 92.3 percent win rate. And barring the occasional result where a P2 creeps up into the lead pack of DPis, most races have highlighted another fact we’ve known all along: the average pro-am lineup in a P2 car is no match for the stunning speed and consistency most DPi driver rosters can offer.

We’re left with race results that continue to defy IMSA’s grand wishes for DPis and P2s to trade poles and wins on a regular basis, and it’s fostered the obvious need for a wholesale change in how the Prototype class is facilitated. Unshackle the DPis, let the factories race among themselves for overall honors, and give the pro-am P2s a championship within a championship where they are untethered from the manufacturer entries.

The current entry numbers skew heavily in favor of DPis, and that won’t likely change in the years ahead. Among the full-time Prototype entrants, Mid-Ohio featured nine DPis and five P2s. Once the Spirit of Daytona Cadillac DPi team returns for Detroit, the number should be back up to 10, giving DPis a 66-percent share of the class.

Image by Levitt/LAT

Just as IMSA has said all along that it would balance the DPis to match the best P2 chassis, it has also been consistent in saying it would not break from the spec rules for P2s to make them faster. As a result, Prototype’s majority has been dragged down to wherever the minority finds itself at a given track. Watching the race trackside at Mid-Ohio, the DPis were especially hapless in traffic, all thanks to the ongoing cuts in power.

The estimates vary from each manufacturer, but most DPis started the season with something in the 575hp range and have been wound down to approximately 515hp to give the P2s a chance. No wonder they’re struggling to get by GT cars. Knowing how the BoP sanctions have not given rise to P2 competitiveness, we’re faced with DPis running slower than possible for no reason.

And, in light of the frequent BoP changes, consider the money being wasted by DPi manufacturers to improve their machines while the series pumps the brakes on behalf of a few P2s. For any car companies looking into DPi, the budget-wasting precedent must be a concern.

Rather than continue to apply BoP changes that needlessly frustrate the manufacturers (rumors of a ‘come to Jesus’ meeting with IMSA on the subject made the rounds at Mid-Ohio) and fail to deliver the real-world competitiveness the P2 owners seek, it’s time for the blended DPi/P2 experiment to end at the conclusion of the season.

It’s up to IMSA to decide whether using driver ratings system for a pro-am P2 championship is needed. I’d suggest that with all the aforementioned shortcomings in budget, resources, and top-tier driver talent in most instances, ratings wouldn’t be required. A proper customer P2 team is never going to be a match for a factory DPi program. And if a major team – an Andretti Autosport, or similar – turns up with an all-pro P2 lineup, it wouldn’t be hard to call it what it is and move the team into the DPi championship frame.

IMSA has two distinct types of Prototype entrants, and celebrating those differences without making unreasonable technical alterations to one type of car is the first step towards greater happiness. Giving the pro-am teams a title of their own to pursue is the other.

When DPis comprise most of the Prototype grid, yet face regular sanctions and still continue to own the P2s, something has to give.