For camshafts we turned to Jim Wolf Technology for a set of their excellent, tried and true C2 camshafts. We have had very good luck with C2’s on SR20s with small frame turbos. The C2’s feature a really high lift of 0.500″ with a duration of 275 degrees. The JWT C series cams must be used with their springs.
The JWT springs’ harmonics are computer matched to the lift characteristics of the cams ramps to reduce high order harmonic excitation. With careful design, spring surge can be avoided with a fairly low seat pressure, lower tension spring. This gives you much less friction, lower wear and less overall stress on the entire valvetrain.
This design methodology is pretty unique to JWT and thus it is important not to mix and match JWT cams with other brands of valvetrain parts. JWT’s design technique makes their cams the most powerful and widest powerband cams for any given duration of any Nissan cams we have tested.
The JWT C2 cams are ground on brand new chilled iron billets that have rheological compatibility with the factory Nissan cam followers for a long service life. Close attention is paid to lobe base circle run out which helps ensure good cranking compression and a smooth idle.
We have found that we prefer to run the C2’s straight up although JWT recommends advancing the exhaust cam a few degrees to increase blowdown to drive the turbine and to reduce overlap.
JWT springs are made of exotic Kobe vacuum degassed chrome vanadium spring steel, the best, most inclusion free spring steel in the world. The springs are nitrided and shotpeened to improve fatigue strength. The JWT cams and springs can safely run up to 8000 rpm but we will limit our engine to 7500 rpm to reduce the chances of the rocker arms flying off on the rev limiter, a common issue with SR20’s when drifting.
Meet Freddy. Freddy is an ancient Greddy SR20DET Intake manifold that has been in the family since the late 80’s. Most lately Freddy served on the first iteration of Project LSR S13’s engine. We think this is the 5th or so car Freddy has been on. It has been on two friends street S13s and another friend’s drift S13 way back in the day before Formula D even.
Freddy is all corroded from Bonneville salt and has turned a weird color from dirt, seasoning from years of oil and old age. The Greddy logo fell off a few cars ago I think when the drift car got totaled. Freddy has the distinction of serving on one of the first dedicated drift cars built and has set a world land speed record.
Before Freddy got installed on Project LSR he got Extrude honed. This is where an abrasive paste is forced through the manifold at high pressures and velocities to port it out. Extrude honing can get where die grinders can’t reach. It is a little hard to see but the port runners are all nice and smooth and shiny from the process.
Freddy’s plenum is all smooth from the extrude hone process as well. At one time somebody had ported Freddy’s inlet to match a larger throttle body. I sort of recall that Freddy made 18 more whp on someone’s car with no other changes at some point. Freddy’s runners are about half the length of the stock manifold and the plenum is larger so it should wake up a FI SR20. Freddy is sort of the Red Violin of intake manifolds, traveling through time from car to car.