M20 Head & Engine Guide
From a stock-style rebuild to a high-horsepower turbocharged stroker, there’s more than one direction to take your M20 engine. But what separates Touring, Super Sport, and Race, and how do the standalone cylinder heads compare with the long block engine packages? This guide walks through the head work, component choices, and bottom-end differences that set these offerings apart.
Jump to: Cylinder Heads | Long Block Engines
A Cylinder Head Or A Long Block Engine?
A standalone cylinder head lets you pair our head work with your existing bottom end or one built by a local engine builder. Our long block engines combine a rebuilt cylinder head and bottom end in one assembled package, with the specified parts, block preparation, and machine work included.
Each long block includes the corresponding Touring, Super Sport, or Race cylinder head, but some components that are optional on a standalone cylinder head come standard on the engine package.
Comparing The Cylinder Heads
All three are built on an OE BMW 885 casting. Each receives cleaning and pressure testing, precision resurfacing, new Supertech valves and guides, new seals, and replacement rocker arm hardware, eccentrics, and studs. The differences are in the port work, springs and rocker arms, and available camshaft and valve options.
Touring: Stage 1
Our Touring head is a stock-style build for street cars, high-level restorations, and lightly modified M20s. It’s unported and includes new Febi OEM replacement rocker arms, with a choice of valve springs. It’s also the only level offering a new OE-spec camshaft for a factory-specification rebuild.
Touring? No, we don’t mean the wagon. The name is a nod to vintage “touring” engine builds, where the emphasis is on dependable running, smooth power, and enjoying the miles behind the wheel. That’s the spirit behind our Touring builds. Increased cargo capacity, however, is not part of the package.
The Touring head is also a foundation for stock-style race builds, including Spec E30, PRO3, and applicable NASA, BMW CCA, and SCCA classes. Racing customers should confirm their class rules before selecting build options.
Super Sport: Stage 2
Our Super Sport head features hand-ported and polished intake and exhaust ports for improved airflow, helping your M20 make more of its performance potential.
Choose new OE BMW dual valve springs or BimmerHeads performance dual valve springs, paired with Febi OEM replacement or KM Cams forged steel rocker arms.
The Super Sport head is where BimmerHeads started. In 2011, we listed a hand-ported M20 885 cylinder head for sale on the R3VLimited E30 forums. It wasn’t called Super Sport then, but it was the first of the heads we still build today.
M20 Super Sport 885 Cylinder Head
Race: Stage 3
Our Race head combines our most extensive hand-porting and polishing with combustion chamber polishing, a step reserved for Stage 3. Built for improved airflow to support high power output, it’s the head we recommend for high-horsepower stroker and forced induction builds.
BimmerHeads performance dual valve springs and KM Cams forged steel rocker arms are included on every Race head, rather than offered as optional upgrades.
Exclusive to Stage 3 are the larger 284 and 284/280 camshaft profiles and the +1mm oversized Supertech valve package. For builds calling for maximum flow, the oversized valve package includes larger intake and exhaust valves and the machining required to fit them.
Comparing The Engines
Every long block engine we build is run-in and tested on our custom-built engine stand before shipping. We break in the camshaft, check for oil leaks, and inspect our work before the engine leaves the shop. We take the time to get each engine right, not just get it out the door.
Touring 2.5L
Our Touring engine brings the same stock-style approach to a rebuilt 2.5L long block, suited to street cars, high-level restorations, lightly modified builds, and stock-style racing.
It pairs a Touring-spec cylinder head with a bottom end built with Mahle 84.5mm pistons, a reconditioned OE BMW crankshaft, and new ARP connecting rod bolts.
As with the standalone head, you can select an OE-spec or performance camshaft. Choose new OE BMW dual valve springs or BimmerHeads performance dual valve springs.
Super Sport 2.5L
Our Super Sport engine brings hand-ported head work and an upgraded valvetrain to a 2.5L long block, offering a step beyond a stock-style rebuild without going to a stroker.
The Super Sport engine comes standard with BimmerHeads performance dual valve springs and KM Cams forged steel rocker arms, bringing together the upgraded valvetrain options offered on the standalone Super Sport cylinder head.
Choose Mahle OEM 84.5mm pistons at the factory 8.8:1 compression ratio, or Mahle Motorsport 85mm forged pistons at 10:1 for a higher-compression, naturally aspirated build. Either piston package is available with OE BMW head bolts or ARP head studs.
Race Stroker
Our Race engine pairs our Stage 3 cylinder head with a bottom end built around our M20 Stroker Kit, including CP-Carrillo forged pistons and Molnar H-Beam connecting rods. It combines increased displacement with our most extensive head work for a high-horsepower naturally aspirated or forced induction build.
As with our Race head, the Race engine’s camshaft and valve options include the Stage 3-exclusive 284 and 284/280 profiles and +1mm oversized Supertech valve package.
Choose 2.8L, 2.9L, 3.0L, or 3.1L displacement. Our standard compression ratios are 10:1 for naturally aspirated builds and 9:1 with the turbo upgrade, with custom ratios available at no additional cost. The turbo upgrade adds heavy-duty pistons and wrist pins, along with Molnar Power-Adder connecting rods.
Whether naturally aspirated or turbocharged, every Race engine comes standard with ARP head studs, an ARP main bolt kit, an oil pan baffle, a Gates Racing timing belt, and a billet timing belt tensioner.
Finding The Right Combination
Some camshaft profiles are offered across more than one build level, but the camshaft is only part of the equation. Port work, valvetrain components, displacement, and compression all help determine how the engine performs.
We’d love to hear about your car, how you use it, what’s already been done, and what you have planned down the road. Our goal is to help you choose the right combination for your build, which doesn’t always mean choosing every upgrade. Whether you’re considering a cylinder head or a long block engine, we’re happy to talk through what makes sense for your needs now and your plans for the future. You don’t need to have it all figured out before reaching out.
Each product listing covers the available configurations, full specifications, current pricing, production timing, core requirements, and shipping details. For installation references, valve clearances, torque specifications, oil recommendations, and break-in guidance, see our Spec Sheet.