Project 350Z: Building a New Engine Part 3

by Mike Kojima

In our last edition of Project 350Z we started to assemble our VQ35DE and got the bottom end pretty much done.  Now we finish off our engine and take it to Church Automotive Testing to get our factory ECU tuned using the UpRev Osiris tuning package.

As we have stated before, our goals are not to build the most powerful NA VQ35DE but simply to freshen up our car's engine which had seen many street and track miles, making it good for more track beating. We also wanted to address early VQ35DE weak areas such as the oil pump and rod bolts and overall rod strength.  If we could get a little more power at the same time, that would be great.

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Our stock heads were in pretty good condition so we sent them out to have a three angle valve job with just a light touch up to the seats.  Since we are not really going for big power, we didn't bother with headwork.  If we were going to do big power, we would have went to the later VQ35HR heads which flow much better.
We reassembled the heads using our previous Jim Wolf Technology valve springs, the stock valves and decided to use genuine Nissan lightweight alloy DLC buckets from a late model engine.  The DLC buckets should work great with our WPC treated camshafts.  Like the valves, our valve guides were in real good shape and didn't need replacement.
As you can see our valves are still sitting high on the seats even after the valve job.  There is plenty of wear left to go here and the flow should still be fine.  When the valves get thin in the margins and sunk down into the combustion chamber, you have to start thinking about slightly oversize valves or even new seats.
The heads were placed on our completed block and torqued down.  With ARP studs we could use a higher tightening torque. With our newer VQ35HR gaskets with improved cylinder seal and water flow path, we figure this will be bulletproof.


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Wednesday, August 26, 2015 8:22 AM
Why not try some e85?
Wednesday, August 26, 2015 9:34 AM
The exact build I've been wanting to do! I would change a couple things like using the HR heads and adding the pathfinder cooling mod. I have to say I am very impressed with the power this motor made with the gas being what it is there. Awesome write up!!! Great job guys!!!
Mike Kojima
Mike Kojimalink
Wednesday, August 26, 2015 10:47 AM
E85 would be really cool for this engine but this is an economy build and we would have to discover the long term shortcomings of the OEM fuel system to ethanol exposure bit by bit.
Mike Kojima
Mike Kojimalink
Wednesday, August 26, 2015 10:50 AM
HR heads or a whole HR swap would really the way to go for the coolest NA setup but we looked into it and it would not be cheap. The hardest thing would be getting the ECU and wire harness of the HR. Our goal was to get HR Power for less money. This car is really fun to drive, the engine, suspension and brakes all feel great.
Wednesday, August 26, 2015 8:03 PM
Yeah I just rebuilt the fuel system from the fuel cell forward. Mine made some pretty good gains after e85 at 330 on that same dyno with a stock block.
Sunday, August 30, 2015 4:53 AM
This would be so killer in a G sedan. Wish you had some videos of it running.
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Monday, September 21, 2015 11:37 PM
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