mtcookson

Yeah, VG30DETT and VG30DE rods are the same... actually I think the VE30DE has the same rods as those as well.

Pictures! Left to right: 84-86 VG30ET, 89-94 Maxima VG30E, 90-96 300ZX VG30DETT Left: 84-86 300ZX VG30ET Right: 89-94 Maxima VG30E Left: 89-94 Maxima VG30E Right: 90-96 300ZX VG30DETT In these pictures the angles screw up the way the rods look. The Maxima rod looks the thinnest of all of them however it is the same thickness as the VG30ET rod (left). Left: 84-86 300ZX VG30ET Right: 89-94 Maxima VG30E Left: 89-94 Maxima VG30E Right: 90-96 300ZX VG30DETT Left to right: Z32, Maxima, Z31 (Yes... that piston from the VG30ET is scored all over. There is even a small chunk missing out of the side of it. Whoever messed with that engine before we got the car had no idea what they were doing... that thing was in such bad condition that I'm having to put in a totally different engine. I'm thinking they tried turning up the boost without adding any fuel and/or an aftercoole. There's a manual boost control in the car... yes in the car... without any supporting mods, so I'm guessing they definitely had no idea what they were doing.) Higher resolution: http://www.machzracing.com/pictures/vginternals1.jpg http://www.machzracing.com/pictures/vginternals2.jpg http://www.machzracing.com/pictures/vginternals3.jpg http://www.machzracing.com/pictures/vginternals4.jpg http://www.machzracing.com/pictures/vginternals5.jpg http://www.machzracing.com/pictures/vginternals6.jpg http://www.machzracing.com/pictures/vginternals7.jpg http://www.machzracing.com/pictures/vginternals8.jpg http://www.machzracing.com/pictures/vginternals9.jpg http://www.machzracing.com/pictures/vginternals10.jpg http://www.machzracing.com/pictures/vginternals11.jpg

yeah, i just had no way of doing it. i mean... i could have put the engine in but if it were bad that would have been a ton of wasted work. however, now that i know what the problem was i'm definitely putting the engine in now.

lol, definitely. This is a 84-86 Maxima VG30E that I'm going to put into a 300ZX Turbo. The original engine wasn't taken care of very well either and its pretty much toast... would need new pistons and such. I'd prefer using the Maxima engine anyways for the extra compression (9:1 vs. 7.8:1) as its not too overly high and should make some awesome low end power.

The VG30E in the Pathfinder should be identical to the engine in the 89-94 Maxima with the VG30E, which is the same as the VG30E in the 87-89 Z31. I believe one of the Z31 guys making something like 500 whp was using a Pathfinder block so you should be ok. I believe the manual transmissions offered in the Pathfinders were 90-96 300ZX manual transmissions, which are proven to be very strong. You should be able to use the 300ZX N/A 5-speed if you wanted to go that route. If you want to stay auto, most reputable performance transmission places can build up just about any auto tranny to handle the power. Did some measuring on the rods last night. I don't have the numbers written down but the Z32 rod is a bit thicker than the other two rods so that's likely where the majority of its extra strength comes from. Still, the stock rods are going to handle some abuse so if you're looking to pull a good amount of power, I'd skip past the Z32 rods and go with some aftermarket rods (Eagle, JUN, Tomei, etc. etc.) They should handle even more power but more importantly should weigh less which will help produce more power.

Figured out the problem... apparently whomever worked on this engine last flipped the cam gears around (left on right, right on left). I guess they just looked at the engine from the front and thought the right side was the driver's side and the left side the passenger (right is passenger, left is driver). Luckily the gears are only half a tooth off from each other so there shouldn't be any valve damage. I'm putting it all back together now so should hopefully have a running Z31 by the weekend.

When I was comparing the Maxima rod to the TT rod, the wrist pins looked identical. Actually, the pins themselves looked the same between all three however the TT rod had more metal where the wrist pin goes as did the Maxima rod. I don't believe I've seen the new FAQ yet but I'm definitely going to go take a look at it now. Its definitely amazing how well built these engines are from the factory.

Ehh... that thing isn't going to break. I'll have to read through my book again, but now that I think about it there's a good chance Electromotive made that 1200 hp using the stock crank. I don't remember them ever saying they made a crank for it but I'm going to read it again to make sure. Either way, that thing definitley won't be breaking for a very long time.

So, while working on my brother's Z31 Turbo I decided to pull a piston and rod out of the bad engine and compare it to a TTZ piston and rod. The only differences between the dish of the two pistons was there were 4 reliefs for the TT piston (for the 4 valves of course). The skirt of the TT piston was slightly shorter but not by a whole lot. (I'm going to attempt to cc the dishes of both to find the exact differences.) The rods were very similar. The Z31 rod was ever so slightly thinner... not really thinner as in the total thickness but, the very edges of it were flatter on the Z31 rod. Over all they were very close to being the same. The major differences were where the rod bolts to the crank and where the pin is for the piston. The early Z31 engines had pressed in pins whereas the Z32 used a floating pin locked in by clips. The top of the rod where the pin goes was slightly larger on the Z32 piston and where the rod is on the crank, there was a bit more material compared to the Z31. Also, while I was doing that I finally pulled a piston and rod out of my old Maxima engine to compare the three. The results were pretty damn cool. The rod of the Maxima is almost identical to that of the TTZ rod. Both use a floating pin and visually look like the same size (I'll measure them tomorrow if I can get out there). The beams of the two rods looked identical. The only major difference was, again, where the rods connected to the crank. The Z32 had slightly more material than the Maxima rod. What does all this mean? This means that the Maxima rod will likely handle a good amount of abuse before it goes. We actually already know it'll handle 400-500 whp in a Z31 without issues (Pathfinder block, stock internals, should be identical to the Maxima block). The Z32 rods supposedly will handle 600 hp. I wouldn't be surprised if the Maxima rod could get damn near close to that. What else could this mean? Well, this also would likely mean the Z32 rod isn't a very substantial upgrade. If the only differences are in the cap, your money would likely be better off going to some aftermarket rods (Tomei, JUN, JWT, Eagle, etc.) I'd say likely the first thing to go (besides the pistons of course) would be the rod bolts. You could put in some ARP studs to be on the safe side but in the end, these things will likely handle more than enough power for some extreme fun. Basically after comparing all of these setups tonight, if you're looking to make good power do not worry about the stock rods. The pistons will definitely be the first to go so I'd put in some good pistons first (http://www.brcperformance.com for high quality, excellent priced pistons). From there if you think you'll be making enough power to hurt the rods or better yet just want to reduce the weight of the internals, you can get some good aftermarket rods. Really that'd probably be the only reason to get them, is for the decreased weight. Maybe if you're planning on making some extreme power (500+++) then a full build like that would definitely be in order. The Maxima engine is a W-series VG30E so it is basicaly identical to the 87-89 300ZX engines. The VG30E's from the Pathfinder and pickup trucks of the same years should be the exact same as well. I know the last year the Maxima had the VG30E was in 94 in the GXE models. I believe the Pathfinder and pickup might have gone a bit longer with it before the switch to the VG33E, but I'm not positive. Either way, this should keep those of you worrying about hurting these VG's from freaking out too much over how much power it'll handle. Have fun!

i made a mistake on the DE(TT) combustion chamber cc's. i believe its actually closer to 49.5 cc. i believe you'd see roughly a .7 decrease in the compression ratio if you used a DE(TT) piston in a E(T). i'm not possitive but from what i've been able to add up that's roughly the difference.

Basically what happens when you vent metered air is the engine will run very rich when you lift the throttle. If for instance you're driving hard then lift the throttle to stop/slow down most of the time the engine will die due to running rich and you'll need to restart it (unless you blip the throttle to keep it going while doing that). Another thing that can happen is it can run rich enough to bog the engine between shifting gears so that you won't have full power potential in the next gear. It can be detered using a programmable ecu or piggy back fuel controller but the easiest way would be to just recirculate the air back through the intake.

You can use the rods but the pistons would likely hurt you more than help out. The combustion chamber of the VG30E(T) is quite a bit larger than the VG30DE(TT). 55 for the E(T) vs. ~44 for the DE(TT). The VG30DE pistons would probably do a bit better than the TT as they would come out to roughly 9:1 however they're designed for an engine with 4 valves and therefore has 4 reliefs for the valves. Since the sohc VG has 2 it normally has 2 reliefs (turbo models use a dish). I'm not sure... but there may or may not be interference with the reliefs. You can actually get some custom pistons made by BRC (http://www.brcperformance.com) for very reasonable prices. Being that they've made some for the Z31 guys in the past there's a good chance they already have all the specs to make them pretty quickly. That would likely be your best alternative.

They both seem like equally stout engines. I personally prefer the VH45 because Nissan tends to put out a bit more power stock for stock compared to Toyota. You also get an increase in displacement and they're proven to be extremely stout. Like you mentioned above though, there might be a bit more aftermarket support for the Toyota engine. However, I believe there might be some more stuff coming out for the VH with the sudden surge of VH swaps that I've noticed. In the end, I don't believe you can go wrong with either engine. They're both very strong and have their good and bad points so it's basically up to you.

do you guys happen to know the opening/closing times when the vvt is on and off? i've been trying to figure out the best way to set the vvt on an n/a motor with some boost and am not sure which would be best. for instance, an n/a motor likes a lot of overlap and from what i understand when the vvt kicks in there is a large increase in overlap. is it the opposite for a stock turbo engine (vg30det(tt))?

yeah, no one ever went against the fact that those engines have forged cranks and rods that i know. its the vg30e(t) that people weren't sure about. it has a cast crank and forged rods from what everyone can tell.

I wouldn't consider custom manifolds a lot of modification compared to making a supercharger setup work. I know someone makes a kit for it (in australia i believe) and as mentioned in the first post there's a kit being made but if it were a custom setup there would be a lot more modification required. I'm sure there would still be quite a bit of modification to make the setup work. Not to mention it would likely be more expensive and would likely never have the power potential of a turbo VG unless it were a screws style s/c (whipple, lysholm, etc.) making it very, very expensive.

I'm actually not for sure but I'd say they're likely all the same. I've never searched for any JDM VH's so I don't know all of the differences.

I believe they were in the Cima and they were in the Nissan President for sure. I can't think of any others at the moment.

I should add that this engine has been sitting in the garage for a while as well. It hasn't been cranked over in at least 6 months I believe. It does have oil in it and surprisingly the oil looks real good (previous owner must have got an oil change before pulling the engine I guess )

When doing a compression test, should the compression numbers always be in spec even if its not spinning very fast? For instance, I have a VG30E that I'm unsure of the condition. It supposedly burned oil however when taking it apart I found a good amount of oil in the intake manifold which makes me think possibly the PCV was bad. Anyways, I only had it sitting on the floor and did a compression check as it sat. Somewhat cold, maybe 50 degrees or so, intake off, one exhaust manifold off, no accessories on it nor even the crank pulley, really the only thing on it was the timing belt and the flywheel and starter. We used a battery charger to test it and it wasn't quite spinning as fast as it would when cranking the engine in the car... maybe 150-200 rpm if that. The readings were only around 120 or so, some at about 90 psi. Basically I'm trying to figure out if the engine is indeed bad or if the readings were quite off due to the circumstances. Thanks in advance for any help you guys can offer.

I have an old Mazda rotary pickup that I'm going to redo (eventually) and I'm actually thinking about putting a VG30E in it (possibly with a turbo). I'd either use the KA24 or the VG30 as those have tons of low end power and both can handle quite a bit of power boosted. Not to mention they are very inexpensive anymore.

Yeah, the VG30 is an awesome engine. my brother wants me to put one in his S14 so I'll likely be doing a similar setup in it as well.

The idea I've always had for a turbo setup in an early Z with a V engine was to route the manifolds forward and put the turbo in front of the engine. That would give you so much free space you could use the biggest turbo you could find up there. I've only figured this out by looking at everything but do you believe this would be an option?