CA18. Sounds like a name of some distant star or galaxy. But not….it is a name of small feisty engine, made before nineties…to propel one of the iconic small Nissan turbocharged cars. Sold in Europe and producing 175hp, it was a nice little car to drive, especially being RWD.
The owner of this one had a completely different wish. POWER.
First step was a bit different than usual. He actually changed the engine into small Nissan’s big brother, RB25. In the same time, owner decided to transplant the gearbox too. The only problem was….burnt piston.
So, the only natural way to progress was building the engine from the scratch and along the way, make it potent 600hp unit.
Then, we all know how RB25 is. Weak. Single small turbo. Less displacement than RB26. Small cams. Almost like neglected little brother.
So we addressed that.
In came the twins. BW EFR6258’s paired with bespoke Milletech exhaust manifolds and complete 3″ exhaust system, with HJS metal hi-flow cat included. All ceramic coated for corrosion and heat protection.
Intercooling was handed over to Mishimoto 4” thick racing unit. With both turbos blowing, a big unit is needed to cool the charge air properly.
Then…..the intake. What to do? As exhaust side was solved, the intake should pair up.
The decision was made. DBW ITB’s from BMW S54 engine, paired with bespoke Milletech intake plenum, all controlled with, of course, Emtron KV8 ecu.
Milletech welded ITB’s to RB25 intake flange, keeping the water-cooling, and paired all to plenum. Custom made high flow injector rail was made, as long with vacuum tank, so the brakes could still work as stock.
Head went through major overhaul. Polish and ported by CHP, it received a pair of Tomei Poncams and 24 oversized Supertech valves with bronze valve guides. HKS stopper head gasket keeps the combustion pressure under control, tightened by ARP head studs.
Wiring, ECU, sensors….
Complete control was handed over to Emtron flagship ECU, KV8. All available sensors were added to engine and around, to keep everything under control, as much as it is possible. Knock sensors added for individual knock control, dual Wideband lambda sensors used for perfect air-fuel control. EGT sensors added to keep an eye on exhaust temperatures and dual turbo speed sensors monitor turbocharger compressor speeds. All is monitored on the digital dash, armed with many alarm functions. Emtron’s KV8 communications through CANBus works perfectly.
Control of the fuel pump, fans, but also power windows, side repeater, headlights….was handed over to PMU. CANBus communication between Emtron KV8 and PMU creates powerful and modern chassis control network. PMU powers up the whole car!
Tuning and result
Once all the things were polished, the end result was impressive. At 1.4bar of boost, engine made 580hp. Without any stress, it is one happy engine!
