In our last story, we gave you a sneak peek and a technical overview of the parts we were going to use on our naturally aspirated VQ37VHR engine with some special help from Jim Wolf Technology and Z1 Motorsports. Now its time to assemble our engine and get it ready for installation in this 370Z. First lets go to Jim Wolf Technology to see how our heads were prepared.
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The VQ37VHR cylinder head is a complicated part. The VVEL or continuously variable intake valve lift and timing system adds a lot of complexity to the engine build. We first did our valve job with a CNC Newan valve seat cutting machine that opened up the valve seats for a larger Titan truck exhaust valve. The Titan valve is sodium filled for better cooling and is 1 mm larger for better flow. The Newan machine cuts the seat and blends it into the intake port and combustion chamber in a smooth radius which really improves the flow.
To finish the complex VHR head we went to Jim Wolf Technology as they are experts in all things VQ. To get a perfect valve seal, JWT lapped our valves with a torque plate bolted to the head. The torque plate simulates the distortion of the head being bolted to the block
The torque plate was installed on the heads with some used OEM gaskets and OEM torque to yield bolts.
Here JWT’s Clark Steppler installs the toque plate on our heads. Afterwards our valves were lightly hand lapped to the seats to make a perfect seal.
Now Clark bolts the head to JWT’s flow bench to see if our heads flow like some of the ones they have done for some of there race program VQ builds.
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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