Spool Performance B58 Engine Build

After countless requests, we're officially launching our B58 Engine Build Program.

We’ve debated offering this service for a long time. Frankly, the market is saturated with shops undercutting prices so low that building engines at that rate simply isn’t sustainable — not if you want a quality product. That’s why we never listed it… until now.

But over time, we've had more and more of our customers come to us directly — people who trust our work because they've seen what we’ve done in the BMW, Mercedes, McLaren, and Audi space. We’ve built a reputation that spans globally, and some of our most loyal clients, especially those running our parts, didn’t feel comfortable going anywhere else. After building several B58s privately for customers who had issues or failures elsewhere, we decided it was time to open this option up.

We’re only offering starting from a Stage 2 build — because frankly, like our transmission kit, Stage 1 doesn't make much sense for what these platforms are capable of. We’ve also seen a growing number of head failures tied to OEM or even ARP 2000 head studs, which simply don’t hold up under high boost and cylinder pressure. As the B58 platform matures, power is easier to make — what was once considered groundbreaking at 800–1000whp is now relatively common. That said, making power is only part of the equation — keeping it together is what counts.

Our goal is simple: to offer a reliable, power-capable engine that holds up under real-world abuse.

A quick reality check — built engines are not lifetime engines.

This is important. When you opt for a built engine, you’re getting a motor that can handle more stress, higher power, and tougher conditions — but that doesn’t mean it’s indestructible or will last forever. These engines are pushed harder than factory ones ever were. More boost, more heat, more wear. Over time, they will require service, refreshes, or even full rebuilds depending on how they’re used. That’s just the nature of high-performance builds.

When you purchase this engine, you're acknowledging that. It will outperform your stock engine in every way, but like any high-performance component, it comes with responsibilities. Abuse has consequences — and longevity is always tied to how the engine is treated.

We’re not here to sell you a fantasy. We’re here to give you something that works.

Our Stage 2 is made to hold up to 1200HP.

CP Carrillo Race Pistons | Heavy Duty Wrist Pins  
CP Carrillo Race Rods | Upgraded Bolts  
ARP Custom Age 625+ Head Studs  
ARP2000 Main Studs  
Spool Race Rod Bearings  
Spool Race Main Bearings  
OEM Head Gasket + Spool Fire Rings  
Upgraded ARP Bolts | Oil & Girdle | Pulley  
Custom CNC Cylinder Head Porting  
Custom Hand Porting  
GSC S2 Cams  
GSC Valve Spring with Ti Retainer  
GSC Valves

Our Stage 3 is made to hold up to 1500HP.

Italian RP Platinum Line Pistons | Heavy Duty Wrist Pins  
Italian RP Platinum Line Rods | Upgraded Bolts  
ARP Custom Oversized Head Studs  
ARP2000 Main Studs  
Spool Race Rod Bearings  
Spool Race Main Bearings  
OEM Head Gasket + Spool Fire Rings  
Upgraded ARP Bolts | Oil & Girdle | Pulley  
Custom CNC Cylinder Head Porting  
GSC S2/S3 Cams (Will reach out to customer for preference)  
GSC Valve Spring with Ti Retainer  
GSC Valves

Stroker upgrades available (3.2L/3.4L) , please contact sales@spoolperformance.us for options and pricing.