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2007 Porsche 911 Carrera S M97 3.8L Engine Rebuild

This is a 2007 Porsche 911 Carrera S engine rebuild performed last summer. Luxury auto dealer contacted us with an inquiry and consultation inquiry. They had a beautiful 911 Carrera on the lot. The car ran great without any sign of problems. One day upon engine start-up there was white smoke from the driver tailpipe and a light engine misfire. Upon vehicle inspection it was agreed the engine shall be removed for further investigation. Internal engine damage was anticipated and eventually found. Upon cylinder head removal on Bank 2 the damage was found. Cylinder 5 liner cracked from headgasket mating surface down to the base of the water jacket. The piston dome was washed out with coolant which also washed out oil lubrication on cylinder walls leading to piston skirt and cylinder bore scuffing.

The following work was performed to restore the engine of this beautiful machine to new condition:

Cylinder Block:

  1. new cylinder block from Porsche
  2. oil pump disassembled, cleaned, inspected, gears and their clearances measured, compared to specification, found to be in good working order, lubricated with engine bearing assembly lube, reassembled, and installed on engine
  3. new crankshaft main, rod, and thrust bearing from Porsche
  4. all new piston rings from Porsche
  5. replace one piston with new unit from Porsche
  6. all miscellaneous o-rings, gaskets, head gaskets, and seals
  7. all bearing clearances checked and recorded
  8. all piston to cylinder bore clearances checked and recorded
  9. all piston ring gaps checked and adjusted as necessary
  10. new cylinder head bolts installed
  11. new crankshaft carrier bolts installed
  12. new connecting rod bolts installed
  13. piston dish volume measured and static compression ratio calculated

Crankshaft:

  1. crankshaft washed and micro polished
  2. all journal sizes measured and compared to factory specification
  3. crankshaft found to be in good condition and reused

Cylinder heads:

  1. camshaft cleaned, inspected, and journals micro polished
  2. cylinder heads disassembled, cleaned, and inspected
  3. cylinder heads deck milled equal amount and hand stoned with lapping stone to prepare for metal head gaskets
  4. valves reground using Kwik-Way valve refacing machine
  5. valve seats lapped in by hand and sealing checked
  6. cylinder heads reassembled with new valve stem seals
  7. combustion chamber volume measured and static compression ratio calculated
  8. after head installation on block, cylinder leak down checked

Pictures of the rebuild:

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2009 Aston Martin Vantage V8 engine rebuild

I would like to document an engine rebuild I did last summer on a 2009 Aston Martin Vantage V8 4.7. Engine was seized due to oil starvation and spun main bearings. Even with all bolts loose on the main bearing girdle and me hanging on a 3 foot breaker bar off the crank pulley it would not turn.

I called Lake Forest Sports Cars in Lake Forest, IL for parts. Right away I was told they can sell me everything needed except engine bearings. Those were not available at all. I could have went next door to Imperial Jaguar but I had a better idea in mind. I contacted ACL bearing company to discuss custom bearing options. In the end of the day I was able to source main and rod bearing in tri-metal contruction from the ACL Race Series.

Original fasteners in the engine were torque to yield design. This means fasteners have to be replaced every time then are tightened and loosened. Official Jaguar and Aston Marin literature suggest main and head studs can only be tightened 2 times before requiring replacement. I contacted ARP for custom fasteners. Head stud option from ARP was possible at a cost of almost $1000 for a set. It did not seem bad for custom made studs but the lead time of almost 10 weeks was a definite turn-off. I talked to ARP about main stud as well and they were of great help. They were able to provide main studs at a very reasonable price and short lead time.

I contacted CP/Carillo for forged piston and connecting rod option. Cylinder bores were worn and AM does not offer an oversize piston option from the dealer. I sent a sample piston, pin, clips, and ring pack to CP for measurements. Three weeks later I had a set of forged piston in 0.5mm oversize. Carillo made a set of connecting rods as well. They are H-beam design and actually lighter weight than the stock powder metal units. Carillo rods were made in custom small end size, crankshaft rod journal was machined in custom size, so that an off-the-shelf ACL Race Series rod bearing could be used.

There was a lot of machining involved in repair of this engine. Oil starvation cause then engine to seize, crankshaft damage, camshaft damage, and cylinder head journal damage.

Block machining:
1. cylinders bored/plateau honed
2. crankshaft main journals align honed

Crankshaft:
1. rod journals spray welded
2. rod journals reground to custom size
3. main journals reground 0.010″ under also for custom size bearings
4. custom wood-ruff key machined from 4140 chrome molybdenum steel used for retaining oil pump gear

Cylinder heads:
1. camshaft journals polished(luckily did not require grinding)
2. cylinder head journals align hone to size(way too much oil clearance)
3. cylinder head machined for exit of align hone mandrel in Bridgeport mill
4. cylinder head plugs machine in a CNC to be used after head is align honed

So far the engine has 2,000 miles and runs flawlessly. The car had to go back to the dealer only to have the transmission recalibrated. Flywheel was lightly resurfaced and the clutch engagement point had to be calibrated by a tech.

Pictures say a 1000 words so I will proceed.

Engine disassembled for inspection to find the following carnage:

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2009 Jaguar XF Supercharged AJ34S engine rebuild

STORY:

Local luxury car dealership contacted us regarding an engine rebuild for a 2009 Jaguar XF, supercharged model. The engine starved of oil, developed a major rod knock, and spun several main bearings. Complete engine rebuild was in order. Cylinder bores were severely scored and distorted due to lack of lubrication. Custom CP pistons were designed and manufactured specifically for our application and engine bored 0.5mm oversize. Crankshaft rod journal were severely worn and had to be pre-ground, spray welded, and final ground to size. Jaguar does not sell oversize bearings, thus every journal had to be restored to standard OEM size. There was a lot of bearing material in the oil pan and extensive cleaning/flushing necessary before engine reassembly. Engine reassembled using Clevite bearing guard lubricant. Engine break-in performed using Brad Penn 30W “Green Oil”.

PARTS LIST:

  • CP 86.5mm forged pistons, pins, rings, and c-clips
  • OEM parts:
  • oil pump
  • oil pick up tube
  • rod bearings
  • main bearings
  • thrust bearings
  • main bolts, M10 long
  • main bolts, M8 long
  • 3 new connecting rods
  • valve stem seals
  • head gaskets
  • valve cover gaskets
  • front cover gaskets
  • lower oil pan gasket
SERVICES AND MACHINING:
Block
  • Bore/hone block to size
  • Hand stone deck to prepare for metal head gasket
  • Align hone crankshaft main bearing bores
  • Pre-grind, spray weld, final grind crankshaft rod and main journals
  • Balance and micropolish crankshaft
  • Measure all bearing clearances using micrometers and bore gauges
  • File fit piston rings using Childs & Alberts piston ring grinder
  • Replace front and rear main seals
  • Measure piston deck height
  • Measure piston dish volume for compression ratio calculator
Cylinder Head
  • Disassemble, clean, and inspect all components
  • Check all valves for runouts using v-block and dial indicator
  • Reface all valves using IDL valve machine
  • Hand stone deck to prepare for metal head gasket
  • Check valve spring pressure using Rimac valve spring tester
  • Grind valve shims
  • Replace valve stem seals
  • Hand lap all valves and check seal
  • Reassemble heads
  • Measure combustion chamber volume for compression ratio calculator
Pictures of engine build:
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Differential welding service Mazda Miata

This is a differential we welded for a local drifter. The car is a Mazda Miata. Stock open differential would not work at all and a Torsen differential was too unpredictable for the customer’s liking. This open differential was supplied for welding services. Our differential welding service is different from most people. While most think it is acceptable to remove the back cover, “degrease” the gears with brake cleaner, and proceed with welding, we do not think this is a reliable solution. Our differential welding service involves complete disassembly of the differential, washing and inspecting of components, and reassembly. We check gear backlash before disassembly and afterwards. If it is our of spec, we fix this as well.

We offer this type of differential welding service for $150.

Goal:

  • Weld differential
Labor:
  • Remove differential cover and check gear backlash before disassmebly
  • Label all components and disassemble differential, remove ring gear
  • Clean all components in a parts washer
  • Inspect all components for wear
  • Weld differential
  • Reassembled differential and check gear backlash
Pictures of the process. Click an image for details.
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Differential welding service Lexus SC300 SC400

This is a differential we welded for a local drifter. The car is a 1997 Lexus SC300 5spd. Stock open differential would not work at all and a Torsen differential was too unpredictable for the customer’s liking. This open differential was supplied for welding services. Our differential welding service is different from most people. While most think it is acceptable to remove the back cover, “degrease” the gears with brake cleaner, and proceed with welding, we do not think this is a reliable solution. Our differential welding service involves complete disassembly of the differential, washing and inspecting of components, and reassembly. We check gear backlash before disassembly and afterwards. If it is our of spec, we fix this as well.

We offer this type of differential welding service for $150.

Goal:

  • Weld differential
Labor:
  • Remove differential cover and check gear backlash before disassmebly
  • Label all components and disassemble differential, remove ring gear
  • Clean all components in a parts washer
  • Inspect all components for wear
  • Weld differential
  • Reassembled differential and check gear backlash
Pictures of the process. Click an image for details.
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DIY: Z32 Nissan 300ZX caliper rebuild and service

Today we show the process of rebuild a set of calipers off a Z32 Nissan 300ZX. These calipers were removed from a 1990 300zx, so they are all aluminum front calipers meant to be used with 26mm wide rotors. The rebuild process for all 300ZX calipers will be the same. We rebuilt both front and rear calipers. master cylinder rebuild procedure coming soon.

We can perform the following service at a cost of $200/pair. This price includes the cost of parts, paint, and labor.

Goals:

  • Rebuild front and rear calipers
  • Improve caliper appearance
Parts:
  • OEM Nissan front and rear caliper rebuild kits(seals, o-rings, dust boots, retainers, and grease)
Labor:
  • Disassemble front and rear calipers(remove c-clips, dust boots, pistons, o-rings)
  • Degrease all components in parts washer
  • Mask off piston bores in each caliper half and media blast completely
  • Mask off piston outer surface  and media blast inside of the piston and dust boot mating area
  • Clean caliper halves in parts washer after media blasting
  • Mask off calipers again and prepare for painting with high temperature ceramic paint(powder coating is optional)
  • Reassemble calipers with new OEM rebuild kits.
Below are pictures of the rebuild process:
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IHI VF40 and VF46 turbo comparison

IHI is the main supplier of OEM turbocharger to Subaru auto company. Although there are abundance of different turbo models across Subaru, they are mostly same turbochargers with slight variations. Today we will look at similarities and difference of the IHI RHF5H VF40 and IHI RHF5H VF46 turbochargers.

IHI VF40 is a turbocharger most commonly found in a Subaru Legacy GT, Forester 2.5XT, and Outback for the 2005-2007 model years.

IHI VF46 is a direct replacement for the VF40 on the 2008-2009 model year vehicles.

Similarities:

  • All internal components are the same. Both turbocharger use the same RHF5H rebuild kit: (journal bearings, clips, oil seals, retainers, fasteners, and thrust components)
  • Turbine housings are the same
  • Bearing housings are the same
Differences:
  • Compressor housings are different– Subaru claims to use a “new” 5 arc design which greatly improves flow and turbo response. Upon measurement of both housing the A/R ratio and internal volume seems to be very similar, thus this claim by Subaru seems to be more of an advertising gimmick than an actual engineering improvement.
  • Compressor wheels are different– inducer and exducer diameters are the same, total blade height and count is the same as well. Difference is in the height of the exducer blade tips. VF46 blades are slightly shorter, about 2mm. This prevent purchase of a VF40 CHRA and mating it with a VF46 compressor housing.
  • Wastegate actuator mounting is different– VF40 uses 3 of the 6 retaining bolts to clamp the actuator, while the VF46 uses only 2 of the 5 bolts to perform the same task. There is no advantage or disadvantage to either design. just noting a change.
  • Compressor seal plate is different– VF40 utilizes a smaller compressor seal plate than the VF46. VF40=119.36mm, VF46=130.07mm
Below you will find pictures of components compared: