4RSTD Stock Engine MINI R53 | R52 | Cooper S | JCW

ENTRY-LEVEL REPLACEMENT
The 4RSTD engine is the perfect choice for clients seeking a reliable stock replacement. Whether your engine is simply worn out and in need of a rebuild, or has suffered a catastrophic failure, the 4RSTD replacement engine offers a straightforward and dependable solution.
Designed as a direct-fit replacement for the MINI Gen 1 engine, each 4RSTD engine comes fully assembled, from oil sump to rocker cover, and is prepared for smooth integration into your project. When paired with our Engine Installation Package, it provides a true plug-and-play solution to get your MINI back on the road, fast.

BUILT WITH PRECISION
The 4RSTD block features a carefully inspected bare cast block, precisely machined to accept 77.25 mm upgraded forged Wössner pistons, OEM connecting rods, OEM crankshaft, KING engine bearings, and a brand-new OEM-quality oil pump. The block is then paired with our 4RSTD cylinder head, built from a thoroughly inspected OEM casting and equipped with OEM-quality valvetrain components. During final assembly, the engine is equipped with a completely new timing system, including a brand-new timing chain, guides, tensioner, and timing gears. To complete the build, the engine is assembled using all-new gaskets, seals, and essential fasteners.

4RSTD SHORT BLOCK SECTION

COMPLETELY CHECKED
All engine blocks are thoroughly cleaned, inside and out, to eliminate any debris or residue from previous use. Each casting is then pressure tested and carefully inspected to ensure it is free from cracks, damaged threads, or other defects that could cause future issues. This meticulous process ensures that every block is in optimal condition and ready to perform.

MACHINED TO LAST
All engine blocks are precision-machined to the highest tolerances. Each block is bored and honed to accept oversized Wössner forged pistons, with bores finished to the correct surface roughness, straightness, and roundness, ensuring optimal piston ring sealing. The OEM crankshaft and connecting rods are carefully inspected and machined if necessary to ensure they meet the required tolerances. The block deck is then resurfaced to achieve maximum flatness and the ideal finish for a reliable seal with the MLS head gasket. Finally, each engine is painted to protect against corrosion and external elements.

BUILT TO HOLD
Instead of just replacing piston rings or using OEM-quality pistons, we install upgraded 77.25 mm forged Wössner pistons, offering increased strength and reliability, especially for vehicles running smaller supercharger pulleys or higher boost levels. Combined with new KING bearings and a precision-checked OEM crankshaft and connecting rods, the short block is built to handle demanding conditions with confidence.

4RSTD CYLINDER HEADS SECTION

ENTRY-LEVEL REPLACEMENT
The 4RSTD Cylinder Head is developed for MINI Gen 1 owners in need of a dependable stock replacement. Ideal for daily drivers and lightly modified cars, it’s the perfect solution when the original head is damaged, worn, or missing. Designed to match factory performance, the 4RSTD head is also compatible with basic upgrades like improved intake systems, smaller supercharger pulleys, intercoolers, and free-flowing exhausts. With factory-matched flow and OEM-grade components, it provides reliable performance and drivability, making it a solid foundation for any standard or mildly tuned MINI build.

READY TO PERFORM
Before machining, all cylinder head castings are fully disassembled and cleaned to remove any residual oil, carbon buildup, or debris from previous use. Each casting then undergoes pressure testing and visual inspection to verify it is free from cracks, warped surfaces, damaged threads, or other potential defects. Only heads that meet our quality standards proceed to the machining stage.

MACHINED TO LAST
The machining process begins with replacing all valve guides with our spec-designed guides, tailored for optimal fit and durability. Once installed, each guide is precision-honed to achieve the correct valve-to-guide clearance, ensuring proper stem lubrication and long-term reliability. The head is then fixtured in our in-house Serdi valve seat machine, where all seats are cut using a multi-angle valve job optimized for the flow characteristics of standard intake and exhaust valves. After seat cutting, the deck surface is resurfaced to create a smooth, flat finish, ensuring a reliable seal with the MLS head gasket. Finally, the cylinder head undergoes a thorough cleaning to remove any residual debris or oil from the machining process, preparing it for final assembly.

BUILT TO WITHSTAND
All 4RSTD cylinder heads are assembled using OEM-quality components, including standard-size 30.3 mm intake and 23.2 mm exhaust valves, OEM valve springs with matching retainers and keepers, and Viton valve stem seals. Combined with our multi-angle valve job, the valvetrain is delivered in optimal condition, ready for reliable performance.

ENGINE INSTALLATION PACKAGE
Make your engine swap easier and more cost-effective by adding our Engine Installation Package to your order. To ensure the best performance and reliability from your 4Revision Engines build, it’s essential to use high-quality components that protect your investment. Each kit includes the correct fluids, a belt, all necessary gaskets, a set of spark plugs, pulleys, and a belt tensioner, everything you need for a smooth installation. Compatible with all MINI Gen 1 engines, this package offers the right parts at a discounted rate, saving you both time and hassle.

POWER RATING
The 4RSTD engine is designed to match the power output of a stock MINI Gen 1 engine but features upgraded forged pistons for added strength and reliability. This makes it ideal for setups running smaller supercharger pulleys, improved intercoolers, colder intakes, and higher-flow exhaust manifolds.

WHAT’S IN IT

Short Block
Block – OEM-machined casting
Pistons – 77.25 mm oversized forged Wössner pistons
Crankshaft – OEM crankshaft
Connecting Rods – OEM connecting rods
Oil Pump – Brand-new OEM-quality oil pump
Bearings – KING main and rod bearings
Timing Kit – Complete new kit including gears, guides, chain, and tensioner
Painted Finish – Color on request

Cylinder Head
Head – OEM-machined casting
Intake Valves – OEM 30.3 mm intake valves
Exhaust Valves – OEM 23.2 mm exhaust valves
Springs & Retainers – OEM valve springs and retainers
Valve Guides – Specially designed sintered-metal valve guides for optimal fit and durability
Valve Seals – Viton valve stem seals
Camshaft – OEM camshaft
Lifters – OEM hydraulic lifters
Valve Job – Multi-angle valve job
Deck Surface – Resurfaced for MLS gasket compatibility