We use the top center method to measure cam timing. The engine is turned to a few degrees from maximum valve lift and the turning is stopped and the lift and the degrees are noted. Then the engine is rotated past maximum lift and when the valve lift is the same as the first time noted, the degrees are noted. The degrees are added and divided by two which gives you an accurate estimation of the point of maximum lift. This can be compared to the cam card. Typically the cams can end up being too retarded as head surfacing and block decking have that effect. If this is going on, it is corrected by using the adjustable cam gears.
Here is what the VVEL system looks like. A lot of complicated parts are going on here!
This is what the stepper motor control for the VVEL system looks like.
The VVEL control motor and linkage are installed one per head.
Next the valve covers are installed.
Then the front cover is put in place.
9 comments
Replacing with upgraded oil gear only is sufficient versus full upgrade of oil pump assembly and cover? Always pondered the value in doing so or maybe there’s a horsepower threshold so any insight is appreciated.
Basically the pump capacity is ok, the problem is the gears break at high RPM.
Kojima-san, thank you for sharing your insight so I decided to purchase the full assembly including the billet cover from Boundary. I also opted for their MartenWear for convenience since they also offer this service although there are other things I may reach out to you separately regarding WPC. Stay well.
Other than the bizaro heads the block looks similar to the VR38 and drag racers are pushing around 1100hp out of the stock block, 1700hp with sleeves, and up to 3000 on a billet block.
The VELL is trick but it locks you out of a lot of otherwise simple modifications.
It is pretty close to the VR. With tuning the VVEL system can give you a bunch of power.
What are the benefits from using the larger valves from a titan truck ? Was there any modifications done to make them fit ?
more flow. The seats must be cut for the larger valve.
Hi,
In the build you used the Titan valve is sodium filled for better cooling and is 1 mm larger for better flow. As the VQ35HR is similar will the same valves fit as was done on the VQ37VHR if so what is the OEM part number so that I can purchase them.
Thanks for your many articles on Nissans
Regards
Jim
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