1970 Pontiac Firebird, Pro Touring – 632ci Big Block!

This 1970 Pontiac Firebird now runs a 632-cubic-inch big block making 853 horsepower on pump gas, built by Bulletmotorsports with no expense spared and featured on a magazine cover. But according to commenters with apparent firsthand knowledge, the car originally ran a smaller Butler Pontiac engine already making 850 horsepower and running 9-second quarter miles, sparking a real debate about whether the swap was an upgrade or a mistake. Watch to see the build and decide for yourself.

Not every muscle car controversy is about horsepower; sometimes it’s about which engine had the right to be there in the first place. This 1970 Firebird now runs a 632-cubic-inch big block making 853 horsepower on pump gas, built with no expense spared and featured on a magazine cover. But according to one commenter who claims deep knowledge of the car’s history, that engine replaced something else entirely, a 541-cubic-inch Butler Pontiac V8 that was already making 850 horsepower and running mid-nine-second quarter miles before anyone touched it. What actually happened, and why some fans are still upset about it, says a lot about what perfection means to different builders.

The Engine Under the Hood Now

As it sits today, this Firebird runs a 632-cubic-inch Luchovich big block, one of the largest crate engines commercially available, built with AFR aluminum heads, all forged internals, a high-flow Edelbrock intake, and a Holley 1250 Dominator carburetor on top. According to Bulletmotorsports, the car’s build shop, a dyno sheet documents 853 horsepower on pump gas, a figure that puts this Firebird well beyond what almost any factory muscle car, Pontiac or otherwise, was ever capable of.

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The Engine That Might Have Been There First

One commenter, describing the car in detail, claims it previously ran a 541-cubic-inch Butler Performance-built Pontiac V8 making roughly 850 horsepower on pump gas and running a 9.28-second quarter mile at 147 mph, numbers that, if accurate, were already competitive with the current big block despite being a smaller, Pontiac-specific engine rather than a generic aftermarket crate motor. That same commenter pointed to other YouTube footage showing the car’s burnouts under that earlier combination.

Why the Engine Swap Sparked a Real Debate

For Pontiac purists, replacing a period-correct-displacement Pontiac engine with a Chevrolet-based big block, even one making more raw horsepower, can feel like solving a problem that didn’t exist. One commenter put it bluntly, arguing the car was already perfection before the swap, and questioning why a builder would trade a matching-numbers-style Pontiac engine for outside power just to chase a bigger number.

The Hood Scoop Controversy

Nearly as contentious as the engine swap is the car’s hood scoop, which multiple commenters singled out as the one element ruining an otherwise flawless build, with several specifically requesting a return to a factory-style shaker scoop instead. One commenter went as far as predicting that whoever owns the car today has likely already pulled the current scoop off.

From High School Daily Driver to Magazine Cover Car

Perhaps the most surprising detail in the comments comes from someone who says they personally owned this exact Firebird in the mid-2000s, using it as a daily driver through high school, before selling it to a builder identified as Brett Evans, who transformed it into the fully realized, magazine-cover pro-touring build seen in this video. That kind of documented ownership chain, from a teenager’s daily car to a no-expense-spared feature build, is rare to get confirmed directly in a comment section.

How Crate Engines Changed What’s Possible in a Build Like This

Large-displacement crate engines like the 632-cubic-inch Luchovich big block used here didn’t exist in anything like their current form when this Firebird was new in 1970, and their availability has fundamentally changed what a serious pro-touring build can achieve. Rather than sourcing and machining a period-correct block to oversized specifications, builders can now buy a fully assembled, dyno-proven big block and drop it directly into a decades-old chassis, which is part of what makes 853-horsepower pump-gas numbers achievable on a build like this.

The Pro-Touring Movement’s Approach to Classic Muscle

Pro-touring builds like this Firebird prioritize modern handling, braking, and drivability alongside big horsepower numbers, a philosophy distinct from restomod builds that focus purely on preserving period-correct looks, or drag-oriented builds that sacrifice handling entirely for straight-line speed. Bulletmotorsports’ description of this car as fully dialed in rather than wearing off-the-shelf parts signals a build aimed squarely at that pro-touring balance.

Why Provenance Disputes Like This One Matter to Collectors

When a car’s engine history is disputed or unclear, as the comment section debate over this Firebird’s earlier Butler Pontiac combination suggests, it can materially affect both the car’s story and its value to serious collectors, who often place a premium on documented, continuous history over an engine swap that breaks the chain, even when the replacement is objectively more powerful. That tension between raw performance and historical continuity runs through nearly every high-dollar muscle car sale today.

What a Magazine Cover Actually Means for a Build’s Reputation

Landing a magazine cover feature is one of the clearest external validations a pro-touring build can receive, typically requiring a combination of build quality, photogenic presentation, and a story compelling enough to justify dedicating print real estate to a single car rather than a roundup. For Bulletmotorsports, a cover credit on this Firebird functions as both a marketing asset and a quality signal to future clients considering a similarly ambitious build, since magazine editors are generally selective about which shop-built cars receive that level of coverage. That context adds another layer to the engine swap debate playing out in the comments: whatever the merits of the earlier Butler Pontiac combination, the car’s current 632-cubic-inch configuration is the version that ultimately earned the magazine’s attention and the accompanying dyno-documented 853-horsepower figure, suggesting that from a pure build-quality and presentation standpoint, the swap achieved exactly what Bulletmotorsports set out to accomplish, even if it came at the cost of the car’s earlier, arguably more historically interesting Pontiac-powered identity.

What Happens to a Car Like This Next

Firebirds built to this level of investment rarely stay parked for long, and commenters actively asking where the car is today reflect a genuine interest in tracking high-profile pro-touring builds as they change hands over the years. Given the car’s documented magazine coverage and its 853-horsepower dyno sheet, any future sale would likely draw significant attention from the pro-touring community specifically, regardless of how the ongoing engine provenance debate ultimately gets resolved among the enthusiasts still discussing it.

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