[Mike Delahanty]

Here’s the explanation behind the HP and weight figures that are in the NHRA Classification Guide for the 2015 Mustang EcoBoost.

First some background.

The engines that power new cars today make more HP per cubic inch than those of the 60’s, 70’s and 80s. The engine designs are optimized to get every possible MPG and HP in production form. Many of the race engine blueprint “tricks” that make power in an old Stock or SS engine have been incorporated into your street car. In addition, the advertised HP ratings from the manufacturers have gone up to reflect these performance improvements. As you can imagine, there’s not much HP improvement left to take advantage of when building a new Stocker or SSer. For a number of years, racers have wanted to build “new” stockers from production cars but the high HP ratings (and weight) discouraged them.

Last year at Indy, the drag racing reps from Ford. Chevy and Dodge met with NHRA to discuss this issue and seek a solution that would at least make it “reasonable” to build a new production Stocker that was competitive. After reviewing performance data from the new cars and examples of new cars in the guide it was agreed that the NHRA HP rating for the classification guide would start at 85% of the factory advertised HP. This took effect for any new car added to the guide from that point forward – like the 2015 Mustang EcoBoost that was recently added.

In addition to the HP discussion, weight was also addressed. There is upwards of 500+ pounds of wiring, emissions hardware and other content that can be legally removed from a new car when prepping it for Stock - and even more for SS. Again - with the objective of making it “reasonable” to build a competitive new car, it was agreed that the shipping weight would be 85% of the manufacturers advertising curb weight. This too took effect for all cars added after Indy 2017. BTW, finding “shipping weight” today is not like it was in the past.

It’s important that new production cars be part of Stock and SS – and not just the CJs, COPOs and Drag Paks. Please note there was no plan, “deals” or arrangements to rig the HP or weight to give the new cars an advantage. I was one of the reps in the meeting and I run a 1964 Stock Eliminator car.

One disclaimer – the above HP discussions did not touch on or address any of the HP ratings for the cars that compete in the Factory Stock or SS classes since these are not production level engines.