With a pretty complete engine, we mounted it to the 5-speed Weddle S5 sequential transaxle and started to build the exhaust and induction. I know that the even-fire nature of a flat-6 and the evenly spaced 120* pulses lend themselves to two separate exhaust banks with 3-1 collectors, but for the packaging of this car an equal length, tuned 6-1 system was a better fit. I worked with some industry colleagues to calculate the best
primary length and diameter, then I got to TIG welding all the stainless.
The intake already had the IRIS deleted from the previous forced induction setup so we left it that way. This engine isn’t going to spend much time at low RPM anyway. The air filters are twin Unique Metal Products centrifugal filters common among desert racecars and industrial equipment.
Just about all the AN plumbing and wiring is done now and we’ll be headed to the dyno soon. Engine management is from an old MoTec M48 and HEX6 ignition, Sakata Milspec harness.
Here is a complete list of the components in the build. To sum up, we wanted a low-stress and reliable flat-6 for this car hence going back to NA, big bore sleeves, and a little higher compression. We hope it makes good power and sounds mean.
Build sheet:
Darton Sleeves - 100mm bore
Flex plate cylinder hone and align bore by Danzio
CP Carillo forged pistons
Compression Ratio - 11.6:1
Cometic MLS head gaskets - .040”
ARP head studs
Delta Camshafts - 272 duration
Stock forged Crankshaft - refurbished by Marine Crankshaft
Crower H-beam connecting rods
ARP Rod bolts
ACL race bearings - mains and rods
CP Carillo wrist pins
CP Carillo pin bushings
CP Carillo piston rings
Wrist pin oil squirters
Ported cylinder heads - full valve job clean up skim cut by Paradise Motorsports
Top feed fuel rails and injectors
External LS1 ignition coils
Aviaid Dry Sump pump
Custom billet aluminum dry sump plate
Sakata Motorsports Milspec wiring harness
MoTec M48 ECU
MoTec IEX/HEX 6 ignition
KEP flywheel
KEP stage 3 pressure plate
KEP adaptor plate
KEP 6-puck clutch disc
NGK Platinum plugs
OE Subaru lifters and gaskets
Custom Stainless Exhaust
FAST 1 Bar MAP
Dual UMP filters
DeatschWerks 450cc injectors