Field Update: The Path to First Pour on the Gen III HEMI CGI Block

ACEINC Engineering Blog · Field Update 01 ACEINC Engineering Team · May 2026 · 6 Min Read

Two months ago we kicked off the Gen III HEMI CGI block program with what looked like a clean path on paper. It hasn't been a straight line. Here's where we've been, what changed, and the production plan that's going to put real CGI blocks into customer engines this year.

If you're new to this program, start with Series 01: The Gen III HEMI CGI Block for the why, Series 02: CGI Metallurgy Deep Dive for the material science, and Series 03: CGI vs Gray Iron vs Aluminum for the technical comparison. This Field Update is the manufacturing side of that story.

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01 The Original Plan: Tupy Foundry

We started with the assumption that Tupy Foundry would handle our castings. After deeper diligence on capacity, CGI metallurgy capability, and the economics of low-volume runs, it became clear Tupy wasn't the right fit for what we're building. We pulled the plug rather than force a partnership that would have compromised the block.

The first lesson of this program: the right answer for a 3,000+ horsepower CGI block isn't always the obvious answer.

02 The Pivot: Build Our Own Foundry?

The next move was to scope our own foundry from scratch. We started designing the equipment package and quoting out what a Brighton, Michigan facility would need to pour CGI in-house: melt deck, magnesium treatment system, sand handling, real-time thermal analysis, the works. Vertical integration is core to ACEINC, and pouring our own iron is where we're headed long term.

But the timeline and capital required to stand up a foundry from a clean sheet don't align with getting blocks into customers' hands this year. We needed an interim path that ships product while we keep building toward full vertical integration.

03 AFS Casting Congress: The Network Pays Off

Three weeks ago, we were on the floor at the American Foundry Society Casting Congress. The conference reconnected us with old colleagues, and David, the AFS president, made a series of introductions to equipment suppliers and industry experts that changed the trajectory of the program.

The biggest connection: Nigel Yeomans of Metal Casting Development LLC (MCD Engineering Group). Nigel and I have worked together on engine block programs in the past, and he now consults for companies running casting projects. He walked us through what's actually possible at our volumes with partners that already have CGI capability today.

From there, Nigel introduced us to ferrous foundries that fit our startup goals: shops with the right metallurgy capability, the right capacity envelope for our launch volumes, and a willingness to pour development blocks alongside production work. That short list is what set up the partnership we landed on next.

04 The New Path: ICC and J&B Machine

Two key Michigan partners came out of that work.

International Casting Corp (ICC). ICC can pour our block in Grade 35 cast iron immediately, and they can run our SinterCast Mini system to convert pours to CGI for validation builds and production. Same tooling, similar cores, two materials. Grade 35 for the early development pours, CGI for the validation and production blocks.

J&B Machine, Fowlerville, Michigan. J&B has the spindle capacity and the experience to handle CGI. We met with them to scope the machining package, lock in tooling strategy, and set up the workflow from raw casting to finished, CMM-verified block.

Both partners are in Michigan. The supply chain stays tight, the iteration loop stays fast, and the product stays 100% USA-made.

05 The Production Plan

Here's the next twelve weeks.

Weeks 1 to 6 · Solidification Modeling and Core Package Finish solidification simulation and the core package design. This is the engineering work that determines how the metal flows, where shrinkage and porosity will form, and how the cores have to be configured to deliver clean castings. The core package gets right or every downstream step suffers. No shortcut.

Weeks 6 to 9 · First Pour at ICC in Grade 35 3D print the sand cores. Pour the first blocks at ICC in Grade 35 cast iron. This validates the geometry and core package before we commit CGI material to a pour.

Weeks 9 to 12 · CGI Validation Pours Pour 5 blocks in CGI using the SinterCast Mini at ICC. These are the first true HEMI CGI blocks ever produced. They go on the dyno for the validation schedule: cylinder pressure, thermal cycling, deck distortion, main bore stability, the full abuse.

Week 12+ · First Production Run, Hard Tooling, ACEINC Facility Once the validation blocks pass, we 3D print enough cores for a 25-unit production run. At the same time we start cutting hard tooling for sustained production and move operations into the ACEINC Brighton facility.

06 Why This Path Wins

Three things at once:

1. It ships product. The 25-unit production run is real product, real revenue, and real builds in real engines.
2. It de-risks the metallurgy. Pouring Grade 35 first lets us prove the geometry before we commit CGI to a casting. CGI is unforgiving. Validating in iron first is the right call.
3. It stays on the vertical integration roadmap. ICC and J&B are the right partners for now. Hard tooling and the move into our own facility are the bridge to running this work in-house.

07 What's Next

Solidification modeling is active right now. Core package files head out for 3D print quotes within 4 to 6 weeks. First Grade 35 pours at ICC are 6 to 9 weeks out. CGI validation pours follow immediately, and the 25-unit production run lands inside 12 weeks.

We'll keep posting as the first castings come off the line. The factory floor at ICC, the dyno cell, the first CMM verification. You'll see all of it.

The HEMI CGI block isn't a concept anymore. It's a schedule.

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ACEINC · PERFORMANCE WITH HEART · Brighton, Michigan