BILLET CRANK SHAFT

The JUN crankshaft made from shaving has flexibility in a design as compared with a forge product. A crankshaft designer can determine form satisfactorily. The JUN BILLET CRANK SHAFT is a genuine crank shaft with both the counter weight of ideal form and the excellent balance.

POINTS

The JUN crankshaft made from shaving has flexibility in a design as compared with a forge product. A crankshaft designer can determine form satisfactorily. The JUN BILLET CRANK SHAFT is a genuine crankshaft with both the counter weight of ideal form and the excellent balance.

Compatible with the Strength and the Lightness

A crankshaft is part which receive bent vibration and twisted vibration by explosive pressure and return inertia force, therefore crankshaft should keep strength for corresponding these conditions. This matter should be especially needed in the tuned engine with high power. But improvement of strength becomes to decrease response of engine if to add more fat without consideration. Both strength and lightness are realized by performing stress analysis. SCM440 is used as a material and processing corresponding to the material is performed. It has both strength and lightness by giving heat treatment and a special surface treatment.

The Finishing Touches

In order to rotate a crankshaft smoothly, the accuracy (The degree of a true circle, and surface roughness) of a pin journal becomes important. The crankshaft which polish finished pays careful attention to the degree of a true circle, the surface roughness, and transformation etc... and is wrapped. After a finishing surface treatment, it is wrapped and a friction loss is made into the minimum. Even if it is the weight form in which the rate of balance is excellent however, when the balance of the whole crankshaft is bad or bent, vibration occurs. Dynamic balance adjustment and bend correction were performed and the cause of vibration as much as possible is eliminated.

MATERIAL, FINISHED

JUN Billet Crankshaft VQ35DE

The Point of Lightening

A Common Crankshaft

A COMMON CRANKSHAFT

Since the portion which is distant from a rotational center (journal center) in order to make weight light is removed, the rate of balance falls remarkably.

The JUN Crankshaft

THE JUN CRANKSHAFT

It is got larger effect to have arranged weight in the position which is distant from a rotational center (journal center) when weight is the same. Therefore, the superfluous flesh near a rotational center as much as possible is remove.

The manufacturing process of a JUN BILLET CRANK SHAFT

PRODUCT LIST

ENGINE Method Stroke Weight CRANKSHAFT CRANK KEY*1 PLUG SCREW*1 REMARKS
PART # MSRP(yen)
NISSAN
VQ35DE Billet87.4mm
(+6mm)
--.-1003M-N009 JPY864,0001003M-N501(1)1003M-601(6)*2
RB26DETT Billet73.7mm
(Stock)
21.5kg1003M-N001GJPY453,6001003M-502(1)1003M-602(12) 
S20 Billet62.8mm
(Stock)
20.0kg1003M-N006 JPY594,0001003M-501(1)1003M-602(6) 
TOYOTA
4A-G(Z)E
 latest AE92
Billet77.0mm
(Stock)
12.5kg1003M-T004JPY410,4001003M-506(1)1003M-601(8) 
Billet83.0mm
(+6mm)
--.-1003M-T005JPY432,0001003M-506(1)1003M-601(8)*3
HONDA
B18C Billet87.2mm
(Stock)
15.3kg1003M-H003JPY410,4001003X-H501(1)1003M-601(8) 
K20A Billet86.0mm
(Stock)
--.-1003M-H004JPY410,400   
F20C Billet84.0mm
(Stock)
--.-1003M-H005JPY410,400   
MITSUBISHI
4G63 Billet88.0mm
(Stock)
--.-1003M-M002JPY410,4001003M-507(1)1003M-601(8) 

*1 Inside numeric of () right behind part number is the parts count which is necessary for a set.

*2 Stroke extened 6mm. Special connecting rods for stroker crank shaft is required.

*3 This crank shaft has a stroke of 83mm long. Special piston, rod, and so on for stroker crank shaft are required.