CARS Midwest Tour Adopts National SLM Rules for 2027

Wisconsin super late model racing spent the last three seasons solving the exact problem Kevin Harvick says he wants to solve. In January 2024, the Midwest Tour and a cluster of Wisconsin and Illinois tracks signed on to one shared rule book so a team could tow from Slinger to Madison to the Dells without re-weighing the car or swapping the spoiler. Now the tour is leaving that book for a national one. Unifying the rules is the easy part. The harder question is which unification wins.

The confirmed news: the ASA Midwest Tour, which will race as the CARS Midwest Tour starting in 2027, will adopt the current ULRA Super Late Model rules package next season, the tour said in an Oct. 15 release datelined Woodville, Wis. That follows Oct. 9, when Spears CARS Tour West co-owners Kevin Harvick and Tim Huddleston and Marty Melo’s MDM Promotions announced that ASA, the Championship Racing Association and CARS Tour West would run under one sanctioning body. The three parties “now share ownership” effective immediately, and the merged body starts Jan. 1, 2027, with seven series under the CARS Tour banner. Melo stays on as owner and managing member.

Melo framed the Midwest switch as fixing a fragmented map: “For too long, competitors have faced different rules depending on where they race.” Harvick went bigger: “Our goal is to establish a uniformed rules package nationwide,” with the stated aim of eventually crowning a national champion in both Pro and Super divisions. Teams also got a raise. Every CARS Midwest Tour super late model race will pay at least $10,000 to win and $2,000 to start. The tour’s 2026 purse announcement listed $5,000 to win and $725 to start at six regular stops, so that’s double the winner’s check and close to triple the start money at those tracks.

Two rule books that look alike until you open the hood

The release gives no line-by-line specs; details are promised before 2027. The closest public reference is the 2026 super late model specifications posted for the ASA STARS National Tour, whose file is labeled as the unified super late model rules. Set it beside the 2026 Midwest Tour rule book and the gaps are not cosmetic:

Induction. The Midwest book is built around the Holley 4412, a 500-cfm two-barrel, with a 650-cfm four-barrel reserved for the GM 604 crate and Wegner 5.3-liter packages. The national book runs gauge-legal 750-cfm Holleys on the SSPE, sealed and ACE packages.
Weight. Midwest base weights run from 2,700 pounds (LLM Concept, iron head and block) through 2,725 (Chevy and Ford ACE) to 2,750 for most sealed and crate packages. The national book lists a 2,800-pound minimum base weight, with officials free to add or remove weight on sealed engines. Both cap left-side weight at 58 percent.
Fuel. In the Midwest, the 604 crate runs pump gas, 93 octane maximum, and built engines may use race fuel up to 110 octane. The national book names Sunoco Standard 110 as spec fuel for all events and bans street pump gas.
Engine menu. The Midwest list includes the LLM Concept, Wegner sealed engines, LST 6.2 and the GM 604 crate. The national book lists SSPE, McGunegill, Hamner by PME and Progressive sealed engines, plus the ACE. It sends crate engines to National Pro Late Model rules.

One line in the national book shows how much the Midwest already mattered. It allows the ACE engine “as commonly used in the ASA Midwest Tour” with a 750 carburetor. That’s probably the template for how Melo intends to keep what he called “a rich history of unique engine combinations.” The open question is what happens to the packages the national book doesn’t list, especially the LLM and Wegner combinations that sit at the light end of the Midwest weight chart.

The Slinger problem

Here’s what a Wisconsin team should watch. Slinger Super Speedway’s 2026 super late model rules carry the same unified weight chart, the same 4412 two-barrel requirement and the same Hoosier ST-1/ST-2 tire call as the Midwest Tour book. That’s by design. The 2024 regional agreement brought in Dells Raceway Park, Slinger, Jefferson, Madison International, State Park, LaCrosse Fairgrounds, Grundy County, the Midwest Tour and the Alive for 5 series, with the pitch that teams no longer had to rebuild the car between nights.

If the tour moves to 750-cfm carburetors, a 2,800-pound base and spec Sunoco while the weekly tracks stay put, that work runs backwards. The car that wins a weekly feature at a home track would need changes to race the tour on Saturday. For a one-car family team, that’s carburetors, spacers, ballast and fuel every time the series comes to town. Seven of the 11 dates on the 2026 Midwest Tour schedule were in Wisconsin. The tour can’t afford to be the odd one out at its own venues.

The likely fix, and this is analysis rather than anything announced, is either a phased transition with Midwest-specific allowances or the weekly tracks following the tour to the national book. Either way, the tracks now hold leverage they didn’t have a month ago.

Consolidation cuts both ways

The case for one national book is real. Super late model racing’s crown-jewel races draw from several regions, and a shared package lowers the barrier for traveling teams and gives engine builders one target. It also explains Harvick’s national-champion talk: you can’t crown one if the regions run different cars.

The risk is the other kind of consolidation. One ownership group now controls the national tour, three regional super late model tours, the pro late model tours and the Track TV streaming rights for all of them. A single rule-maker means regional quirks that survived because nobody upstream cared about them now need someone’s approval. The ULRA itself said in its November 2025 pro late model release that “substantial changes” were expected for 2027, with new engine packages developed alongside the Sealed Engine Alliance Leaders. That’s the same year the Midwest joins.

One naming note: neither release ties the new CARS brand to the zMAX CARS Late Model Stock Car Tour, the series whose title fight we covered last week.

What to watch this winter

The technical bulletin. The weight assigned to the LLM, Wegner and 604 packages will show whether the Midwest gets a real seat at the table.
Weekly-track rule books. If Slinger, Madison or the Dells publish 2027 rules that track the national package, the transition is real. If they don’t, teams are buying two setups.
Engine-builder pricing. A move from 500-cfm two-barrels to 750-cfm four-barrels is a parts-and-dyno bill, and those bills hit the smallest teams hardest, the same budget squeeze now reshaping development programs higher up the ladder.
Schedules and Track TV pricing, promised in the coming weeks.

Wisconsin already proved short-track teams will sign on to shared rules if the rules fit the cars they own. The new owners have the money and the momentum. What they need now is a rule book Slinger can live with.