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*Updated: 02/06/2022 5:26PM PST

Building a VG34 and installing it in my '88 Pathy


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This is the story of how I ended up building a VG34 engine for my '88 Pathy and how it all went together. I'll start with a little background on the engine, who "invented" the VG34, and what Nissan used it for. Please note that all of the installation information applies to a VG33 swap into a truck that came with a VG30.


Background: The VG34 was invented by Nissan Motorsports' engine builder Sly. He developed it for use in the factory off road race trucks that competed in the Baja 1000. For whatever logistical reasons they needed to be able to run Mexican pump gas in the trucks so they only wanted about 10:1 compression ratio. With this low of a CR flat topped cast pistons would be more than strong enough... and the right ones just happened to be in the VH45DE engine in the Infiniti Q45. The "Q piston" as it's known is 93mm in diameter with a 22mm wrist pin. A stock VG33 block is 91.5mm and the cylinder walls are *very* thick so boring 1.5mm (0.060") over does not require sonic testing. (Please note that the VG30 block's bore of 87mm cannot be increased for even stock VG33 pistons, the cylinder walls are not heavy enough!) VG30Is & VG30Es have 21mm wrist pins that are pressed into the rods. VG30ET and all DOHC VGs have full-floating 22mm wrist pins. VG33Es have 21mm full floating wrist pins. All North American VGs have the same length connecting rods and the same stroke and this makes it very easy to mix and match parts. The most commonly used rods for a VG34 build are the VG30ET ones. They are quite strong and good for more than 500hp with no prep work but they are heavy. VG30DE rods are much more common and lighter so they are a better choice unless massive power with boost is the goal, in which case Carrillo rods are the ticket. It is also possible to re-bush the stock VG33 rods which are good for 400hp and that is what I did.


My 'old' Pathy motor: I bought my Pathy with a blown motor. I pieced together an engine with the 60k mile bottom end out of my parts truck and a set of brand new early Z31 heads I had sitting on the shelf. This engine ran great it's whole life but about two years ago started pressurizing the cooling system with exhaust. It did not have a blown head gasket, it had either porosity in a head casting or a crack between a water jacket and an exhaust port. I put 130k miles on this motor in the five or six years I've had the Pathy. The truck used a little water when run hard but never overheated until the last 1000 miles or so. The leak apparently got much worse and I massively overheated it a couple of times. I mean it got hot enough to boil every bit of water out three times on it's last trip and I felt I was lucky to get home without using my tow truck!


The VG33ER: While looking for a HD automatic transmission for my friend Dennis' Pathy I saw a supercharged VG33ER engine and trans with 48k miles on Craigslist. I was broke so he bought it for the $800 the guy was asking, I went and got it with my Pathy:






For the record, that's a whole lot of weight in a soft-sprung Pathy on 33s with no sway bars! The drive home was sketchy to say the least. I had 150psi in the left air shock and 100psi in the right so the Pathy sat level, kinda. The harness was cut and there was no ECU or anything else not directly bolted to the engine. The plan was to swap the whole works into Dennis' '95 Pathy until we found out how much it costs in electronics to make one of these run in a vehicle it didn't come in.


I turned the engine over several rotations with a breaker bar on the crank nut before buying it and it felt completely normal. When I got it home I sealed up the intake and exhaust manifolds and stored it inside. A few months later Dennis traded me the engine for installing the SHD (Super Heavy Duty) S/C Xterra transmission into his Pathy. When we went to turn the engine to remove the torque converter I was unpleasantly surprised to find a tight spot. Damn, must be some rust in there somewhere!


Fast forward a couple months and my Pathy desperately needs a motor. So I pull the ER motor out and take the supercharger and related parts off (everything above the heads) and sell it on eBay... for a thousand freaking dollars! That made my day, let me tell you! So I proceeded to take the ER engine apart to see if it could be just be honed. This is what I found:




Actually, I didn't take a pic of exactly what I found. That pic was taken after I used my ridge reamer to knock most of the rust out above the pistons. At this point my hope was to hone it and put it back together.

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The really ugly cylinder honed out clean and would have been fine but number one cylinder had a rust pit about 1/8" in diameter half an inch down from the deck... not gonna work! Hmmm, it was time for Plan B: Overbore it to make a 3.4 liter!


The rest of this story is in pretty much the order I took or uploaded the pics so it may be a little disjointed in places as I work on one thing while waiting to get parts for another or whatever, sorry!


Dennis and I took the engine apart and he put each individual bearing shell into a ziplock bag and marked them with a Sharpie so I could put it all back together exactly as it was. The bearings all looked like brand new so there was absolutely no reason to replace them. I put the crankshaft in a garbage bag and sealed it up so it wouldn't need to be cleaned before re-assembly.


A mechanic friend gave me this 100k mile Q45 V8 about five years ago.




It's been sitting on a stand in my garage collecting dust until now. VH45 motors are almost worthless as they rarely fail and the cars they came in are super cheap so nobody fixes them. I tried to sell this a couple times but nobody wanted it... so I said screw it, and swiped the pistons out of it for my Pathy. The pistons looked great, with only very minor wear showing on a couple of them. I only needed six of the eight so of course I used the best six. I switched the media in my blast cabinet to corn cob and Dennis blast-cleaned the pistons for me while I worked on something else. They came out looking like brand new. The great thing about corn cob blast media is it takes carbon, paint, and just about anything else off but won't even take the shine off of a polished aluminum surface.


I dropped the block off at my favorite automotive machine shop where they work on American V8s exclusively... plus my stuff. :sly: The owner really had to look close to see that the piston I took for sizing was not new.


There was a little bit of rust, more like water stain marks, on some of the valve seats so rather than taking a chance I decided to have the valves and seats ground. I wanted to port the steps out of the exhaust ports and you really want to grind the seats last in case you mess up and ding a seat with a die grinder. Next up is some cylinder head info.


There are two styles of VG heads, the early V52/21V casting and the later 85E/OWO casting. The 85E castings came out in mid '87 I think in Z31s. These are the heads of the "W series" VG30 that everybody wants due to their better intake port shape and cams. The OWO heads are found on all VG33 engines and are the same casting as the 85E but use the larger 10mm exhaust studs. This pic is a comparison of port molds of the early vs. late VG heads:




You can see that in the early port the air rams into the far wall and has to make a 90 degree turn to flow past the valve into the cylinder. Not so good. The later heads are a HUGE improvement but left as-produced they do not flow any better because the exhaust ports are screwed up. There are big steps just above the valve seats that effectively reduce the diameter of the opening by about 3/16":








It's kinda hard to tell in the pics, but that bright ring 'inside' the exhaust seats is a step that should have been machined out. I have no idea why they left these steps, a slight change in the shape of the cutter used to cut the seat pockets would have taken them out with no increase in machine time. These pics are after I ported the steps out:








There were also some minor steps in the intake ports:




So I smoothed them out while I was at it:



Edited by Mr.510
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I also "ported" the spark plug drain channels since this motor is for a wheeler. Here's a before and after, you can see the casting mismatch and flashing was almost completely blocking the channel that's supposed to drain water out of the spark plug wells and into the valley:






I needed to re-bush my connecting rods for 22mm wrist pins so I machined a draw bolt tool to remove the old bushings without damaging the rods. This is the tool and the 21mm bushings:




Next up was turning some new wrist pin bushings from silicon bronze:




I cut the ID to exact size at 22mm and the OD for a .003" press fit. When they are pressed in the ID shrinks about .005, and that's what my guy wanted left for finish honing. These are pretty thin bushings so I made a draw bolt tool to install them without folding them into origami:




Bushing on the tool's arbor:




And pressing in a bushing:




The shoulder of the tool seats against the connecting rod ensuring that the bushing is perfectly flush:




Next up I drilled the oil supply holes through the bushings on a Bridgeport:




I took the rods and heads to my guy so he could finish hone the bushings and touch up my valves and seats.


The VH motor is a DOHC four valve so the valve relief notches aren't even close to being in the right place. I borrowed a friend's piston vise and set it up on a Bridgeport mill to duplicate the stock VG30's valve reliefs in the Q pistons:



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The mistake many people make here is that they duplicate the VG33s much deeper valve reliefs rather than those of the VG30. VG33s have huge valve reliefs as a means of lowering the compression ratio that went up when the bore size was increased. Contrary to 'internet wisdom' the deep valve reliefs and crap cams in VG33s do not make them non-interference, all VG engines can bend valves if over revved or if the T-belt fails! If you duplicate the VG33 valve reliefs in Q pistons the piston crown is scary thin at the bottom of the reliefs and the compression ratio drops to a bit less than 10:1 I would guess. Down the road a little ways I intend to turbocharge this engine with a stock Z31 turbo pushing 5-7psi with no intercooler so scary thin piston crowns were not even remotely acceptable! I CC'd a piston so I could accurately compute the compression ratio. The six valve reliefs together total 0.8 CCs:




Next I went and got my block, heads, and rods. We ran the block and heads through the Hotsy high pressure parts washers at a friend's work for a couple hours to make sure they were squeaky clean. The start of assembly at last! The two oil drain back diverter plates that keep the oil from the heads from pouring on the crank overhang the enlarged bores:




I marked them in place with a Sharpie:




And increased their radius using the bottom wheel of my belt sander. Here is one installed:




After putting the oil diverter plates in it was time for the crank! I polished the rear mail seal surface lightly and dropped it in with my favorite engine assembly lube, Hilton's Hyper Lube. There is electrical tape on the rod journals to protect them in this pic:




Jalapeno Pringle Power for the WIN!




Jalapeno Pringles are the official snack food of VG30.com!




I didn't think to take any pics of the rods and pistons before I put them in. But here they are installed:




Next I put the valves in the heads. The VG33ER valves are ceramic coated from the factory which is pretty darned cool. They also don't have the Nissan logo on their faces like virtually all Nissan valves clear back to the '60s. Smooth valve faces is a good thing as there are no 'hot spots' to cause detonation. Valves installed in a head:




I tell everyone they can generally get away with cheap aftermarket junk parts on their Pathies except for three pieces that MUST be Nissan factory parts: The timing belt and both head gaskets. Of course I used Nissan head gaskets, and the heads are on:



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My Pathy had W series Z31 cams in it so I wanted to use them in the VG34. They are the best stock cams in the North American market. So the next thing I did was pull the VG30 out of the Pathy:




Upon removing the RH cam I discovered that the cam retainer bolt had fallen out and the cam had been walking back and forth in the head. It also had no oil pressure to lube the lifters for probably a very long time. This engine had a funky tick the last 100k miles or so that was not a collapsed lifter, I think it was this:




The rearmost lifter was keeping the cam from walking any further forward. It could move about 1/4"! That rear lifter was acting like a roller to keep the cam in place and you can see in the pic above where it ate into the rear bearing area. Funny how it cut the cam lobe profile into the side of the rear bearing journal! There was no other apparent damage to the head, the lifters or lifter plate, or the cam even though it had no pressure to pump oil out it's holes for a very long time. VGs are tough! I dug around and found a set of 85E heads on my cylinder head rack and stole the cams out of them instead. I didn't take any more pics of the inside of the motor.


The first clearance issue I ran into was one of the oil pump's bosses for the timing cover was in the way of my power steering pump bracket:




I just ground a notch in the bracket:




The next thing I had to deal with was the lack of a short-nosed 4x4 water pump for the VG33. The VG33's oil pump extends higher up on the driver's side to allow mounting of the oil filter housing. Here are the two pumps side by side:




I used the VG33 water pump gasket to mark the VG30 pump:




And cut the offending piece out on the bandsaw:




I also cut off that sharp point in the above pic, but didn't take a pic of it specifically. The VG30 water pump isn't thick enough where it meets the oil pump to use the stock round rubber seal. This is just there to keep mud and water out of the timing assembly so I used Nissan gooey gasket (silicone) instead:






The VG33 oil pump has the pickup tube attached on the opposite side of the crank as the VG30. I produce modified "crossover" pickup tubes for VG510s, Z31s, etc. and didn't know if I would have to build one for the Pathy swap. It turns out the '03 WD22 oil pan is exactly the same as the '88 WD21 oil pan except for a slight change in the shape of the angled surface where the drain plug is. The drain plug on the WD22 pan is slightly lower so more oil drains out when the plug is removed. The good news here is that the stock WD22 oil pickup tube fits perfectly in the WD21 oil pan so no modification is required. Here's the motor with the WD22 pickup tube installed and ready for the oil pan:



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Becuase I intend to turbocharge the Pathy at some point it will need a fitting in the oil pan for the turbo oil drain to connect to. I TIG welded a 1/2" NPT weld fitting into the RH side of the oil pan in the one spot a line could go between the power steering pump and the motor mount:




I intend to produce top-mount turbo headers specifically for the WD21 that locate the turbo more or less where the battery is stock. Chances are these headers will also fit WD22s since they are so similar. The thing is, I haven't prototyped them yet and there's a chance I'll end up putting the turbo on the LH side instead. There's nothing important there on TBI trucks (rusted out air injection crap) and the stock air box on MPFI trucks that probably can't be used with a turbo anyway. Just in case I also TIG welded a turbo drain fitting on the driver's side, between the motor mount and alternator/oil pump:




Both of the motor mounts in my Pathy were broken when I pulled the engine. I knew the driver's side was broken, that's the third one I've popped I think. This was the first passenger's side I've broken, must have been gettin' some in reverse! Low range is definitely hard on mounts. I didn't want to spend the money on the Rugged Rocks mounts plus I really don't want stiff mounts that transmit a bunch of vibration to the chassis. One of the great things about wheeling my Pathy is that it's quiet, smooth, comfortable, and loaded with every option. It's rough on the outside but the interior is really nice and the truck is completely civilized and a joy to drive on tarmac. Here's the solution to broken motor mounts:




The chain I used is 5/16 HD load chain. I chose it because the link length was exactly right, not because it's 700% stronger than it needs to be! The idea with chains on the mounts is that they do not effect the amount of vibration transmitted to the chassis unless I'm on the throttle in low range. So I end up with the best of both worlds: Smooth, low vibration operation on tarmac and mounts that will never break no matter how hard I abuse them... and I don't really abuse stuff anyway. If the two free links rattle I'll add a throttle return spring that pulls them forward to stop the rattle.


This is the prototype of my newest product, the VG33 Six Bolt Crank Adapter:




It's a billet aluminum hub that replaces the harmonic balancer on the VG33 and allows use of any of the six bolt VG30 crank pulleys. The small spot drill dimple is TDC for #1 cylinder. This is a feature the stock VG30 balancers should have had so you could tell which of six ways to put the damned crank pulley on so the timing marks are right!


This is the mill fixture I made in order to make the adapter as well as to be able to reverse engineer the timing mark locations. The fixture locates the part within 1/10 of 1 degree so the bolt holes end up in the right place and the engine can be properly timed:




And here's the Crank Adapter installed:




That's the VG33 lower timing cover. It has to be used as the bolt holes are in different places plus the hole for the crank pulley hub is larger than the one on the VG30 cover. The upper timing covers are the same except for the tabs for wiring and plumbing so I used my original ones.


With one pulley on the Crank Adapter:




And with the power steering pulley bolted on:




You can just barely see the aluminum lip that centers the pulleys when it's put together. In the truck you cannot see it at all. Production parts will be anodized to inhibit corrosion:




The timing pointer was way too long as the VG33ER had a super deep crank pulley with the outer section driving the supercharger:



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I pruned it back with tin snips and also bent it down as the VG30 pulley is much smaller diameter than the VG33ER one:




Looking straight down. You can see how the timing pointer is about right and the VG30 water pump pulley lines up perfectly with the crank pulley:




This is my customized RH valve cover:




I started with the VG33 one as I really wanted the filler neck. I cut off the vent connection at the front and also cut off the PCV elbow deal near the back. I welded a pipe plug into the hole in the front as it was a perfect fit and sawed the PCV nipple off a smashed 300ZX valve cover and welded it to the stub I left sticking up from the original PCV nipple. This way I can use the stock PCV hose and I don't have any stupid rubber caps or other crap to leak on the front of the valve cover.


This is a good trick, especially on 4x4s:




After the oil pan is installed fill in the gap behind the saddle seal with gooey gasket so mud doesn't pack in there and corrode the rear mail seal housing away until it leaks around the outside of the seal. I've seen some seriously destroyed RMS housings from corrosion over the years.


Time to bolt it into the Pathy! Here's a few pics of getting it in there:








Here it's sitting in place:




I replaced my steering box, power steering pump, and center link while the motor was out. I left the starter connected to the wiring and just sat it on the ledge under the radiator. The A/C compressor and alternator were left connected and sitting behind the LH headlight. The easy way to put a VG in, especially with an automatic, is to leave the RH exhaust manifold and motor mount off. This way you can easily see to line up and torque the torque converter bolts with a long extension while holding a wrench on the crank nut with your other hand. Getting the starter into place and it's wiring clipped in and installing the motor mount are much easier without the manifold there.


TBI mods: The TBI injection has a ceramic mixture preheater directly below the butterfly. It's an electric heating element that kicks on in really cold weather (I think) to heat the A/F mixture for better combustion. These heaters have a habit of getting crumbly with age. When a chunk falls out of the heater it generally destroys the engine. I highly recommend removing this on any TBI truck unless you wheel in Antarctica. Many people, even in Eastern Canada, have removed them with no apparent ill effects in any kind of weather. Here's the mixture heater though it's already been removed from the insulator plate:




And here's the insulator plate without it, shown from the top:



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The mixture preheater was riveted to the plastic insulator plate. I ground the heads off the rivets with a teeny cutoff wheel on my Dremel. This left some odd recesses and there was a step for an O-ring that would probably create some funky turbulence at the throttle plate. I ground the steps and stuff mostly out with a die grinder, making the bottom a large chamfer, more or less. Then I filled the rivet holes and the remainder of the O-ring step and other recesses with intake port putty. The next day I shaped that with a die grinder and then sanded it to final shape with a drum on my Dremel. The hole at the bottom of the insulator plate is now slightly smaller in diameter than the bore in the intake manifold. This whole project took about half an hour, so it was no where near as much work as it sounds! This is what the finished part looks like from the bottom:




Like 95% of the TBI intakes I see the EGR port was packed solid with carbon and had probably been non-functional for hundreds of thousands of miles. I've turned more than 50 TBI plenums into two barrel Holley carb intake manifolds so I've seen the inside of a LOT of intakes! Externally sanitized:




I put the intake on and started hooking things up:




And then I discovered this:




It's the tell-tale sign that the intake gaskets are too thin making the intake sit too low and mis-matching the intake ports by 1/8" or so. The VG30 gaskets are a piece of steel sheet about 1/16" thick with neoprene seals snapped into them. The VG33 gaskets are about .010 thick stainless steel with raised lips around the ports. I had read on a forum that you needed to use the gaskets that go with the heads, so if you've got 8mm studs run thick gaskets, with 10mm studs run thin gaskets. WRONG! Freaking internet wisdom. I take pics of all the stuff I do so people can see that I usually know WTF I'm talking about and they aren't going to get an unpleasant surprise when they can't get parts for several days. </rant> Anyway, VG33 intakes are machined wider so the ports line up when using the thin gaskets. The heads are all the same size. So if you've got a VG33 intake run thin gaskets. If you've got a VG30 intake run thick gaskets! After changing the gaskets:




The next thing I ran into was that the boss on the oil pump housing where the alty tensioner attaches is .300 thicker than the VG30 one. Hmmm, alty tensioner doesn't line up. I *thought* I could just put a spacer between the alty and the tensioner bracket like this:




My alty belt shrunk:




The VG33 oil filter housing sticks out from the block a bit so the atly cannot swing in as close to the block. When I got a belt that worked I discovered this:




The Alty belt rubs the tensioner bracket. Since the spacer between the alty and tensioner doesn't work I decided to make an offset alty tensioner real quick like. Because the atly can't swing in as far there would not have been very much belt adjustment so I decided to stretch the mount by 1-1/4 inches while offsetting it .300 to correct for the thicker oil pump boss. Fifteen minutes later I had this:




I then applied my patented "baked on enamal" by spraying it with engine paint while it was still around 500 degrees. Here's a few pics of the finished part:



Edited by Mr.510
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And bolted in place:




The VG33ER may have had a bracket that would just work but that was missing when we got the engine. My brother told me the VG33 altys have the tensioner boss offset closer to the block so the tensioneer bracket can be shorter than mine. I don't know if you could run the VG33 alty on the VG30 upper bracket with the VG33 tensioner?


Oh man, really? It had not registered in my head yet that the oil pump boss on the RH side was .300 thicker as well. The lower radiator hose steel tube bolts onto the oil pump. With the VG33 oil pump the steel tube interferes with the power steering belt big time. There may be a VG33 part that solves this problem, but I didn't have one so I did this:






Baked on enamel finish at the weld, and bolted in place:




I also had to squish the tube a little bit to gain clearance where the belt could rub at the top. This was largely due to my thermo housing hose being really thick so it might not be necessary with a factory hose. That was a five minute project, from the time the light bulb came on until I finished bolting it to the motor. I hope when people find bolt-on solutions to any of these problems they will post them in this thread! It's no big deal for me to make or modify stuff but whenever possible I try to find bolt-on solutions for all the people that don't own fab shops.


Trans cooler: When I did my '01 Xterra HD transmission swap I replaced the radiator so it had a good heat exchanger for the transmission. Massively overheating the old engine the last time out turned my ATF a little darker than I'd like and I can't use that heat exchanger anymore. My brother got me the wholesale hookup on a Hayden 24k pound rated transmission cooler. It's the plate type that apparently does a pretty good job of not over cooling the fluid in Winter:




While the engine was out I also drained the transmission, pulled and drained the torque converter, filled it with Amsoil synthetic ATF, and indexed it back in.


Well, that's actually about it. Everything you didn't see just bolted together the way it was designed too. When I first fired it the thing ran like crap. It was trying to run at about 300rpm but I was happy to see that even at at that low rpm it only took about five seconds for the oil pressure light to go out. I couldn't get it over 1500 rpm and figured I'd screwed up the TBI somehow. It turns out I had the distributor a tooth off! Derp. After that quick fix it fired right to life and purred like a kitten. I timed it to the stock setting. I had been running the VG30 advanced seven degrees and that made a definite increase in power. I don't need to push this new motor to the ragged edge as it should have plenty of power... for now. :cool:


In the video it sounds like either the alty is screaming for mercy or the T-belt is too tight. Neither is the case. It's just the way the mic on my D2 really picks up higher pitched sound. The engine sounds completely normal in person. I can't get the video link to work right so you'll have to click the link:




I've now put about 40 miles on the engine driving it around Seattle. The steering box I swapped in while the motor was out has a tight spot in the middle so I have not taken it on the freeway yet. All I can say so far is it hauls balls! It's the quickest Pathy I've ever been in, that's for sure. It has some serious snap, pulls hard to redline and has a huge increase in bottom end torque. I cannot stall my torque converter on dry pavement anymore as the truck starts crabbing sideways with wheel spin before it reaches 2k rpm. Stall speed is 2200. My butt dyno says if the VG30 made 150hp this one is well over 200. :) I look forward to surprising some ricer Honduhs with it! :aok: I will get some 0-60 and quarter mile times with the dyno app on my Droid 2 as soon as I get the steering fixed.

Edited by Mr.510
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Very cool. Your engine compartment is dirty though :laugh:


So, does it make a difference that you essentially don't have a harmonic balancer anymore?


I think I used the wrong intake gaskets... aftermarket ones were pretty thin... oh well.

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Cool stuff man! Im glad to see that Nissan guys both use very similar tactics when working on a engine rebuild. Though I have never done much more than a rebuild from small block, a few tricks you used I have used as well for a long time. If you ever decide to drive that thing for a long test drive, come down my way! I would love to check it out! Good work!

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Wow that is a great write up!!! :aok:


I wish i had the time and motivation you have!


Thanks man! It was fun to build. Removing and installing engines in Pathies is the hard part for me with my screwed up back. They're an SOB and one of the reasons I ran the old motor with overheating problems for so long!


Very cool. Your engine compartment is dirty though :laugh:


So, does it make a difference that you essentially don't have a harmonic balancer anymore?


I think I used the wrong intake gaskets... aftermarket ones were pretty thin... oh well.


People on facebook were giving me crap about the dirty parts bolted to my new engine. I'm like, this thing is gonna see maybe 100 miles of tarmac and then all that crap is gonna be covered with mud anyway so why waste time cleaning stuff that doesn't need to be cleaned? :lol: As far as I can tell there is no difference in felt vibration without the harmonic balancer. Many people have run aluminum 'power pulleys' on Z31s that eliminate the balancer and there doesn't seem to be any adverse effect on crank life or bearing wear. I am going to shoot a video comparing engine vibration between a stock VG30E and my VG34I just to see if a difference can be seen in the ripples in a glass of water. Worst case with the wrong gaskets you get a mismatch in the intake ports, that would probably only cost you 5hp on an MPFI motor. On a TBI it could be a whole lot worse since the fuel is already mixed with the air when it gets to that mismatch.


Impressive amount of work and knowledge in that build along with a great write up. Good job... :clap:


Now, let's see how it runs... :D




Thanks! Videos will be coming soon. Just gotta get the steering box sorted out so I can stand on the skinny pedal for more than five seconds at a time!



There are a couple things that I should have included that came to mind when I re-read the above. One is a comparison of bore and stroke:


VG30 87mm bore 83mm stroke 2960cc displacement

VG33 91.5mm bore 83mm stroke 3275cc displacement

VG34 93mm bore 83mm stroke 3380cc displacement


Another is compression ratio. The valve reliefs measure 0.8cc and the combustion chambers in the heads are 54cc. I forget the volume of the compressed head gasket but my compression ratio comes out to 10.312:1 so I call it 10.3 to 1. The increase in compression ratio is a much bigger factor in how much power it makes than the increase in displacement. At 10.3 to 1 it runs perfectly on 87 octane with the initial timing set to 10 degrees. I expect I can probably advance it a few degrees if I want to, but TBI motors don't have knock sensors so there is a little bit of risk in doing so. I did install a knock sensor under the intake in case I decide I want one... my brother once wired one up to make an LED light up as knock was detected and used it as a tuning aid on a race engine that was far too loud to hear pre ignition knock. I may do the same.

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Cool stuff man! Im glad to see that Nissan guys both use very similar tactics when working on a engine rebuild. Though I have never done much more than a rebuild from small block, a few tricks you used I have used as well for a long time. If you ever decide to drive that thing for a long test drive, come down my way! I would love to check it out! Good work!


Going to Evans Creek on Tuesday for it's first trail run and to test out my newly installed front LSD, you should call in sick and come along! :)

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I was all set to read and look at pictures. And then I saw the corner of the yellow Bluebird. Any more pics of it?


That's my baby. It's a 1970 Bluebird SSS Coupe'. Here's an old pic of it:




excellent write up

that cam looks scary :blink:


Thanks! Yeah, pretty wild. It's funny, I've pulled the cams out of four sets of VG heads recently and 2/3 of the retainer bolts were barely tight, like 20 ft. lbs. or less! Needless to say I used Loctite on the cam retainer bolts in this build! I'm amazed nothing broke or even wore out, especially that rear lifter and it's bore - they both look like brand new. You know that funky clack noise at idle in all my YouTube wheeling videos? Now we know what it was! :doh:

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I was waiting for this to get asked, and am kind of surprised that it wasn't the first question. How much money are you into it for? I know you have a bunch of things available to you that most people don't. I have access to or own everything i would need, so I am curious. I have been tossing ideas like this around in my head for a bit. Seeing this gets me motivated! Thanks for documenting and sharing!

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Awesome white up! You have skills and a lot of nissan knowledge, and parts. I have a VG33 to put in my pathy and would love to build it into a VG34 but I don't have the equipment to machine those pistons. Doesn't anyone make a .060 over piston for the VG33?

After seeing the problems people run into mixing and matching parts, my plan is to use a VG30 crank in the VG33 block then use a VG30 oil pump and other accessories. I should be able to remove the block plate, add the threaded fitting from a VG30 and put my oil filter on the side of the block like the VG30? I know most people don't like the oil filter next to the starter but it has worked for this long.

Thank you for all the pics, I knew the heads needed work but now I know exactly what to do.

I was planning on converting my fuel injection over to the VG30E setup before changing the motor, I'm surprised you used the TBI setup. That would be alot easier! Do you think you will need to reprogram the ECU to get the full extent of your motor, or are you not worried about it just as long as it runs good?


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