LN Engineering Comprehensive Porsche Engine & Machine Shop Services

LN Engineering offers a wide range of engine machining services to support the RND Engines and Flat 6 Innovations Porsche engine rebuild programs. This includes any custom machine work you may need for your next Porsche engine repair, rebuild, or restoration project. Our machine shop specializes in performing work on air-cooled and water-cooled Porsche engines, however we also provide the same services for any engines that may require specialized services that our machine shop is able to accommodate for your next performance engine build. Whatever machining services you need for your engine rebuild, LN Engineering has professional-grade equipment and decades of knowledge and experience as most everyone on our team are car guys through and through.

LN Engineering is a proud member of and contributor to the AERA Engine Builders Association.

Automotive Machine Shop Services

LN Engineering’s automotive machine shop offers services like Nikasil cylinder reconditioning, aluminum engine block repair and sleeving, connecting rod reconditioning, crankshaft polishing, engine balancing, cylinder head remanufacturing, and more. Each automotive machine shop service is completed by our experienced professionals, using high-quality equipment and their years of expertise to ensure the job is done right the first time.

Cylinder Reconditioning, Case Machining, and Aluminum Engine Block Sleeving

When an engine needs to be rebuilt, cylinder bores need to be inspected for ovality and taper (cylindricity) as well as for proper surface finish. Although Nikasil is very durable, there are times where the plating needs to be stripped and redone to restore a cylinder or bore. Likewise hypereutectic aluminum engines including Porsche engines using Lokasil or Alusil blocks can be bored out and Nikasil plated or may need to be sleeved to correct for any cracks or there is irreparable damage to the cylinder walls, like from cylinder bore scoring. Unlike other companies that use cast iron or steel cylinder sleeves, LN Engineering pioneered the use of aluminum Nikasil plated cylinder sleeves that improve the strength and cooling over other sleeves that reduce performance and longevity. Oversized aftermarket pistons may also be used if the bore, cylinder, or sleeve is larger than the stock bore, providing added performance through increased displacement and compression ratios over stock. Worn aircooled engine cases may require align boring, provided oversize line bore bearings are available, especially magnesium 911 engine cases, that also require shuffle pinning and the installation of cylinder head stud inserts. To ensure leak free operation, case decks should be resurfaced and can also be opened up for machine-in cylinders and o-ringed. This can allow you to save money by reusing the same engine block or case compared to having to buy an expensive factory replacement parts that provide no improvement, or worse, are no longer even available at any price.

Cylinder Head Inspection, Cleaning, and Machining

Cylinder heads can sustain damage such as cracking or become warped due to engine overheating or head gasket failure. An initial assessment ensures the cylinder heads are crack free and do not have any hidden defects. Heads are also checked for warpage, especially in cam bores, prior to cleaning. Our cleaning processes include vapor and soda blasting as well as ultrasonic washing. Cleaning the heads to remove carbon deposits like those found in clogged secondary air injection (SAI) ports or baked on oil residue is often required. Resurfacing the cylinder heads is necessary to eliminate any irregularities or waves, ensuring a leak-free fit against the engine block. This process involves milling, turning, or grinding the contact side of the head until it is perfectly flat and meets original equipment specifications. The gasket surface is machined with CBN tooling to achieve the necessary finish for MLS gaskets. If resurfacing exceeds these specifications, the combustion chamber might become too shallow, risking piston contact with the heads or valves when they are open. Valves are meticulously cleaned, stems are polished, and valve faces are ground to ensure smooth operation. Valve guides are checked for wear. Worn guides are replaced using a honing process to achieve an optimal finish, preferred over reaming, especially for small diameters like 6mm. Valve seats are inspected, replaced, and cut using our Serdi machine and our custom-developed multi-angle and radius cutters, valve seats are precision machined to enhance performance. Valve stem heights are checked and adjusted as needed to maintain critical clearances. Springs are inspected and tested to ensure consistency and reliability. Opting to port and polish or twin plug the cylinder heads as part of the repair can not only restore them to nearly new condition, but also promote improved performance. After a thorough cleaning, the cylinder heads are reassembled with new valve stem seals. Assembled heads undergo vacuum testing to ensure they are sealed correctly and functioning properly. You can rely on our skilled cylinder head expert, who has over 40 years of experience, to expertly restore your engine’s cylinder heads.

Connecting Rod Reconditioning

Connecting rods are crucial for engine functionality, and any imperfections can diminish engine performance. If your engine is undergoing a rebuild, it may be possible to refurbish and reuse the connecting rods, but we do recommend upgrading the connecting rod bolts. The reconditioning process involves cleaning the rods, testing their hardness to confirm the metal’s strength and composition, magnaflux testing for cracks, and checking for straightness. Additionally, the rod bolts and end cap bores are examined for stretch and roundness. Rod bolts are replaced and the caps are ground and big end bores honed to restore the housing bores to factory specifications. Once reconditioned, the connecting rods are ready for reuse in the engine rebuild. Our machine shop also offers services to press and hone new pin end bushings as well.

Crankshaft Polishing, Grinding, and Balancing

If a crankshaft is damaged by normal wear or a bad bearing, it may be able to be refinished and reused. Most Porsche crankshafts don’t need to be ground and can simply be polished as part of the reconditioning process, assuming the crankshaft is straight and has been magnafluxed to make sure it’s not cracked.

If the crank does need to be ground, crankshaft grinding is a process that removes a small amount of material from both the rod and main crank journals to return the crankshaft to OEM specifications, if possible. Most crankshafts can be ground, but some do require heat treating to restore journal hardness to ensure proper longevity. This may require the use of undersize bearings to ensure proper engine operation or even line bore bearings if the block needs to be resized at the same time. The crankshaft and entire rotating assembly can also be dynamically balanced during the process to help ensure the engine runs smoothly. Having a crankshaft polished or even ground can be less expensive than replacing the crankshaft when rebuilding an engine, so let our experienced professionals handle all of your crankshaft polishing, grinding, straightening, machining, and balancing needs.

Other Automotive Machine Shop Services

Our machine shop provides a range of sought-after specialty services required to properly rebuild any Porsche engine. If there is something you do not see listed on our website, you can contact LN Engineering directly to inquire about specific services you require.

Let LN Engineering assist you with your Porsche engine repair, rebuild, or machining project. We stock most everything needed to rebuild your air-cooled or water-cooled Porsche engine, making LN Engineering a one-stop shop for both Porsche enthusiasts and industry professionals alike.

Our Capabilities

At LN Engineering, we are equipped with state-of-the-art machinery featuring Haas 3, 4, and 5-axis CNC machines with Renishaw probing systems to meet diverse machining needs across various materials and can work with Solidworks, Fusion 360, and Mastercam for modeling and CAD/CAM.

With these advanced tools equipped with Renishaw probing and thru-spindle coolant, we deliver precision parts across various industries, maintaining the highest standards of quality and efficiency. LN Engineering also has laser marking capabilities and a dedicated temperature and humidity controlled QC lab and clean room with calibrated precision measurement devices from Sunnen, Mitutoyo, and other high quality instrumentation including VeriSurf CMM and laser scanning for inspection and reverse engineering.

Our Services

LN Engineering is a family, women, and minority owned and operated company with a long history of product quality and customer satisfaction. Our experience developing and manufacturing aftermarket automotive components has aided us in acquiring our vast knowledge of design and machining further bolstered by the skills of our seasoned career machinists with decades of experience. In our facility, our team utilizes 3D CAD drafting, which seamlessly integrates with our CNC CAM program to transfer designs directly to our CNC machines. Our skilled team members assist clients in resolving product issues, reverse engineering existing products, enhancing designs, and creating prototypes. Our experienced staff collaborates closely with you on your projects, guiding you from the initial design and prototype development to full-scale mass production.