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ALUMINUM BLOCK UPDATE FOR 2025

Merrill, MI – After 3 years of allowing aluminum blocks and learning about the pros and the cons, we have simplified our rule for the 2025 Season. Any car running an aluminum block will be required to weigh 1,500 pounds. We will not be requiring additional bolt on weights, we simply will require the car to be 1,500 lbs or more at the scales.

We are still a steel block group and ultimately the 2 largest pros for steel blocks are the motor longevity between rebuilds and the horsepower generated. However we made the decision to allow the aluminum blocks primarily for 2 reasons, availability and repairability. There has been industry issues with steel block supplies and at the end of the day you can’t typically repair a damaged steel block. So it’s up to our teams to weigh the pros and cons and do what is best for their team.

For more information on aluminum blocks and specs allowed, see the schedule listed below or you can find it in the GLSS rules under Section 12.1.2 Titled “Aluminum Engine Block Rules”.

12.1.2. Aluminum Engine Block Rules

1. List of Chevy aluminum engine blocks approved for GLSS Competition are as follows:
2. BRODIX® casting designation- letter A (std. cam location, std. bellhousing, std. pan rail), or I (raised cam location, std. bellhousing, std. pan rail) only.
3. SPEC logo on block is NOT to be modified and must remain 100% legible
4. Absolutely NO lightening of any kind allowed kind allowed
5. Standard or raised cam allowed
6. Oversized cams allowed
7. Roller cam bearings allowed
8. Minimum allowed deck height is 8.970”
9. Maximum allowed deck height is 9.020”
10. Oversized and keyed lifters allowed
11. Must be standard or GS-1 lifter location only. No exceptions
12. Must be standard oil pan rail
13. Full bellhousing must remain
14. GLSS approved Aluminum block part #’s as follows:
    Part # Bore/Main Cam
    8B 1000A 400/400 standard
    8B 1050A 400/350 standard
    8B 1100A 350/400 standard
    8B 1150A 350/350 standard
    8B 1000I 400/400 raised
    8B 1050I 400/350 raised
    8B 1100I 350/400 raised
    8B 1150I 350/350 raised
    Cam and lifter size must be specified while ordering

Great Lakes Super Sprints presented by Engine Pro and ARP will be back in action in April 2025. Stay tuned for more exciting information about our 2025 schedule and 2025 programs.

Check out Michigan CAT at https://www.michigancat.com/ and Ohio CAT at https://www.ohiocat.com/

Thank you to our sponsors and partners who are the ones that allow us to bring a great show to your local tracks. Please help us by supporting the sponsors listed below….
PErfit Corporation
Engine Pro & ARP Racing
Michigan CAT
Ohio CAT
Operating Engineers Local 324
MacAllister Rental
Beacon & Bridge Markets
Hoosier Racing Tires
Engler Machine & Tool
Jim Coffey and Sons Plumbing & Heating
Howard Johnsons by Wyndham
Specialty Fuels & Logistics
Environmental Waste & Recovery Service
Rescue Resources LLC.

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