A Look Inside, Technosquare’s Ultimate Street Car Turbo Nissan VQ35DE


VQ35DE turbo block
The VQ35 has an extremely strong main cap retaining system with a stout girdle and 4 bolts per cap for strength and rigidity. The main bores are checked to see if align boring is needed.  It rarely is with the VQ35DE engine which is fortunate because it’s pretty difficult to do so with a girdle type main cap system like the VQ uses.  The piston cooler oil squirter’s are easily visible here.


VQ35DE Turbo
Cosworth main and rod bearings are used. Cosworth bearings are tri-metal in construction for superior load bearing capacity.  The bearings are select fit just like the OEM Nissan parts for precise control of  clearances.  The bearings have increased crush for a tighter fit to the bore, a thinner overlay for better load bearing and 3/4 grooving for more oil supply.  The odd color is due to the lack of overlay plating which Cosworth omits for improved heat transfer.
Turbo VQ35DE engine build
Howard Watanabe of Technosquare measures the bearing bores with a bore gage.  You cannot measure precise bores for setting clearances with calipers and plastigage!
VQ35DE Turbo engine crank
Surprisingly when the crank on Cheston’s motor was sent out for magnafluxing (a method of crack detection that all used parts should be subjected too) a crack was found on one of the main journals.  This is very unusual as the VQ35DE has an exceptionally strong stock crank.  A brand new Nissan crank was used.  The oil feed holes were chamfered and the press in oil passage plugs removed and replaced with screw in plugs for reliability.
vq35de turbo motor WPC crank
Since the stock crank cracked, the new crank was WPC (a Japanese metal treatment process, to read details check this out) treated to help improve its fatigue strength.  The WPC treatment will help assure that this failure will not repeat itself. The milky look of the journals shows the WPC treatment which also reduces friction and helps hold an oil film on the journals.


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