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Ok it’s been a hot minute since I updated this and I’ve got some juicy stuff for all you high hp guys, the VR38DETT ARP L19 studs came in. To start off with I took some initial dimensional information as a comparison to the VQ35DE ARP L19 studs To start off here side by side visual comparison of the washers used in each kit Their outside diameter is basically the same and the washers from the GTR kit will fit in the machined holes in the VQ35DE cylinder head no problem Obviously the GTR stud is larger and so then is the washer inside diameter Washer from GTR L19 kit in place in the VQ35DE cylinder head, and you might be wondering why I would even check? And the answer is that the OEM GTR head bolt had a larger flanged neck which does not fit into the little machines spots in the head without flushing the surrounding area with the bolt surface. Also there is a little interference with the actual cylinder head casting that holds the lifter buckets that you would have to grind down if you decided to use them I happened to have a few unused GTR studs so Here is the head measurement and as you can see it’s only a few mm larger but because of how long the bolt is and how large the bolt head diameter is if you don’t mill out a little bit of the casting for the lifter guide around the bolt hole you won’t even be able to insert the bolt all the way Side by side comparison of the VR38DETT and VQ35DE studs Compared the the VQ stud with the 3/16 Allen key The GTR stud hex is slightly larger and a 5mm Allen key is perfect for easy installation The GTR stud threads are longer than the VQ stud threads. This is the portion that threads into the block. the length of the GTR stud is significantly longer than the VQ stud, so at least the holes for the 2 front and 2 rear bolts for each head need to drilled 2-3mm deeper into the block to clear the camshafts and the holes must be threaded all the way to the bottom Side by side comparison of the VQ35DE L19,VR38DETT L19, and OEM GTR bolt
So the stud holes in the head are actually not large enough for the studs to fit through so they must be enlarged I decided to use this step bit and drill the holes very slowly by hand. The final step is 1/2” and the step right before it is the exact size of the OEM hole so it works like a guide It’s a snug fit This is what I use in place of drilling or tapping oil. It works really well and is a spray with a straw like WD40 Drilling out the holes even just to the next size up produces a significant amount of shaving. I decided to complete disassemble the heads before doing this to ensure I wouldn’t have any lingering shavings later 1/2” hole is a perfect fit Not a noticeable difference in size really but it will allow us to do what needs to be done BTW the thread length portion of the GTR stud. Here is where things get messy, the GTR studs are much longer than the VQ35DE studs and although some of that length is taken up in threading the GTR studs all the way into the block the studs are not threaded far enough down to just insert them and go There are 2 problems one is that the studs sit too high and will contact the camshaft unless the front 2 and rear 2 studs of each cylinder head are set 2-3mm deeper in the block that means that when you drill out the old threads in the block you need to increase the depth of the hole by 2-3 mm. It should be noted that if you go to far coy could drill into one of the oil lines in the block and you don’t want to do that Problem 2 is that with the stud in place the threaded portion for the nut does not go all the way down to the bolt surface on the head, I’m getting around this by ordering 304ss bolt spacers that have a high enough hardness on the rockwall scale that they won’t deform in use
If this is the path you want to follow the dimensions of the spaces I used are 1”od 1/2” id 3/4” length and you can expect to get them for about $19-24 each and you will need 16 One stud is done and I’ll get the rest finished here soon. I Should also note that the HR gasket I’m using are already large enough for the new studs so off the shelf HR gaskets don’t have to be modified
Small update
drilled out all the old threads from the stud holes and managed to drill deep enough to set the studs away from any valvetrain interference
I set the stop on the bit at 74mm but with the head gasket in place to protect the deck the hole depth is probably around 73mm The small line just above the stop on the bit is how deep the hole is from the factory so you can see roughly how much deeper I’m drilling the holes I masked off everything fairly well All the holes came out perfectly And here is why I masked everything off, just cutting out the old threads and enlarging the hole produced a lot of shaving
I’ll be taping the holes next then I can clean and start assembling
Holes are all taped and cleaned out, spent a little time after work inserting the GTR studs into the block, tomorrow I’ll start installing the cylinder heads
11051011[/url]]Beautiful Rinz - How do you like the mobile1 filters? I like wix and bosch but a buddy swears by those mobile1
I’m not particularly adamant on my filter brand I just happen to trust mobile1 more then the cheap brands, I consider both Bosch and Mobile1 to be top tier brands and would use either, where I live the mobile1 filter is just easily to obtain, I will say that I don’t use the filter for the 350z, I use the filter for the Pathfinder Vq35de it’s a bit larger but that’s about the only benefit
Well the heads did not go on today, ran into an unforeseen snag with the cam sensors. As you can see from the photo below the cam sensor is very close if not interfering with the stud. Action plan now it to figure out if I have another 2-3mm of depth I can drop the stud and if the stud that close to the sensor will cause the sensor to misread. I’ll keep you guys posted
Little update, the heads are on and torqued down with no issues, when tightening the nuts you can definitely feel how much stronger the studs and threads are. It’s hard to explain but I felt like the GTR studs were significantly more solid when doing the final torque round, I am quite pleased 😃 the two bolts that sit directly under the cam sensors were recessed another few mm and do not interfere with the cam sensors anymore. All mods and repairs are done now all that’s left is to re-assemble everything
The deeper studs got 3/8 spacers (left) while the rest got the 3/4 long ones (right)
for those that are interested in the documentation, you can safely drill the rear studs to 80mm deep without penetrating into the coolant line that runs down the center of the block but it should be pointed out that the bottom of the stud holes in the casting is right there in fact you will partially brake through it. Below I will post some pictures I took of a test block I used to test drill depths on. At 76mm you will just barely open up the side of the casting that is adjacent to the flywheel 80mm is open a bit more but still not penetrating the coolant line
76mm deep driver’s side 76mm deep passenger side 80mm deep drivers side 80mm deep passenger side
Do you happen to know how far away your head stud is from your cam sensors? I would think because the cam sensor uses the front of the sensor you should not have any problems, also does not hurt that the cam and cam sensor are only a few MM away from each other. It's more of a out of curiosity question nothing special.
Do you happen to know how far away your head stud is from your cam sensors? I would think because the cam sensor uses the front of the sensor you should not have any problems, also does not hurt that the cam and cam sensor are only a few MM away from each other. It's more of a out of curiosity question nothing special.
it’s about 4-5 mm away it’s hard to get a proper measurement tool in there to get an exact measurement but the cam sensors don’t even pick up the bolts where they are
Weekend update, the long block is fully assembled now and I’ve moved on to everything else, I did end up doing another wire tuck but this time I didn’t cut anything, I unraveled the harness and pulled the extra wire length through the firewall to hide back behind
Still not sure what to do with this side of the ignition harness as the oem sub connector and ignition condenser makes it messy
Small update, car is 95% reassembled with the remaining 5% being interior related. Started her up this morning, after a somewhat hesitant crank she started first try which is a first for any of my project up till now 😂 I moved her from the garage to the driveway under her own power so I could tidy up the garage. I am having an issue with the drivers side fuel level sender which thinks the tank is empty at half tank, I will probably have to replace it as I think I might have scratched the level contacts, I also ordered a chase bays coolant reservoir and a oil catch can for the outlet of the exa pump they will go in with the oil cooler once I finish the tune and engine brake in. As for tuning I’ll be focusing on regular fuel instead of high octane, there is just no need or benefit from it with the 8.8:1 static compression, of course when the turbo goes on that’s a different story and I’ll switch back to high octane. I forgot to take pictures of it but I designed and printed a firewall plate to slide into the slot by the battery to cleanly secure the 0/0 gauge power and ground alternator wires and the fuel signal line that goes from the regulator to the fuel pressure sensor, I plan to do the same for the now empty wire grommets on both sides of the engine bay that the wires for the headlight, horn, washer res, all passed through, since I relocated those wires out of sight the grommets are empty and don’t look good. The large bundle of wire from the main harness tuck fits snugly behind the beauty panel between the engine and fire wall there is just enough room under the ac lines for it all to fit
I will get some pictures when l work on it later today
Here are some pictures How she sits right now The new plate for the alt wires and fuel signal line
Printing plates for the other harness grommets so I can get everything looking much cleaner
I do have a new cold air intake to replace the factory air box but I need to modify it and paint it before I can put it on and it’s not super important atm
Took the car out for a short around the block drive, it’s painfully obvious that with the lower compression it’s producing less torque especially mid range, the electric power steering is a tad bit stiffer than OEM but still pleasant to drive. Loving the JWT clutch, wish I had put one in a long time ago. Still need to get the timing dialed in, I’m hoping I can get more torque from swapping to regular gas and getting aggressive with the timing. Also thinking I may need to ditch the fuel in the tank as it’s almost a year old
Well it’s back to square one, drove the car this morning and cylinder 2 stopped firing,
no codes yet but I’m guessing it’s the same issue as before. really disappointed and frustrated, think I will take a step back and figure it out some other time, I just don’t have the heart to work on it after this
Update: it’s actually cylinder 3 with P0303 and P0300 codes
Decided today that I need to pull the engine and strip it down to the short block. I’ve come to the conclusion that whatever is wrong is either beyond my knowledge or skill level. I’m going to take the heads back to the machine shop and have them do a proper valve job, check everything over maybe they can find what I can’t
05-14-2021, 07:17 PM
