mtcookson Posted February 27, 2006 Share Posted February 27, 2006 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! Quote Link to comment Share on other sites More sharing options...
260DET Posted February 27, 2006 Share Posted February 27, 2006 Crankshaft Eagle rods are well priced, I'm going to use them in the DET, mainly because of their lighter weight. Which should benefit the bearings a bit. Quote Link to comment Share on other sites More sharing options...
mtcookson Posted February 27, 2006 Author Share Posted February 27, 2006 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. Quote Link to comment Share on other sites More sharing options...
Guest Jason84NA-T Posted February 27, 2006 Share Posted February 27, 2006 I have both early ET, late ET and DETT rods sitting right in front of me. I agree completely, the only substantial difference is the wrist pin diameter. W series ET are about the same size as non-w, but are obviously full floating instead of press-fit. I think the only reason a lot of the ET guys run DETT rods when they put in forged pistons is purely to get the use of the very slightly larger wrist pins. I agree that the rod bolts from ARP are a good upgrade as they should be replaced anyway, and for the $60 the kit costs from summit it's a good investment. Again, a lot of this information I already out into the new turbo FAQ. I'm not sure if you have read it yet, but you are probably as used to working with VG's as I am... so your input would be valued if you have time to take a look at it. -Jason Quote Link to comment Share on other sites More sharing options...
mtcookson Posted February 27, 2006 Author Share Posted February 27, 2006 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. Quote Link to comment Share on other sites More sharing options...
260DET Posted February 27, 2006 Share Posted February 27, 2006 From the spring 1996 edition of Z car Magazine, an ad by Class Action Motorsport for 300 to 1000 hp Z31 engines for sale as used in IMSA GTO and GTP competition. Z Rotax block, Carrello(?) rods, billet crank, Cosworth pistons, roller rockers, titanium valves etc etc, weight 280lbs. Be nice to get hold of one of those engines Quote Link to comment Share on other sites More sharing options...
Silent Posted February 28, 2006 Share Posted February 28, 2006 soo. in thinking, the 93-95 vg pathy blocks should be the same in general right? or did nissan do the trick of getting cheap again. have always thought about putting a turbo on my pathy, but just wasn't sure how it stacked up to the z31t bottom end. let alone getting a tranny to hold it {auto is nice for traffic} Quote Link to comment Share on other sites More sharing options...
mtcookson Posted February 28, 2006 Author Share Posted February 28, 2006 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. Quote Link to comment Share on other sites More sharing options...
Silent Posted February 28, 2006 Share Posted February 28, 2006 are they using the pathy heads too? ie long block, or just the short block and the intake manifold? Quote Link to comment Share on other sites More sharing options...
Guest Jason84NA-T Posted February 28, 2006 Share Posted February 28, 2006 I believe it was Ken who made 450RWHP using a pathy block. The heads are the same, and his were only lightly ported as I recall. He made that power on a JWT 4-bar, so ovbiously there was plenty of room for improvment. He was using a Z31 lower and pathfinder upper intake. Quote Link to comment Share on other sites More sharing options...
Silent Posted March 1, 2006 Share Posted March 1, 2006 hmmm damn. 500 hp pathfinder 4wd drag radials on all corners. this sucker would be quick! Quote Link to comment Share on other sites More sharing options...
mtcookson Posted March 2, 2006 Author Share Posted March 2, 2006 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 Quote Link to comment Share on other sites More sharing options...
desert dog Posted March 2, 2006 Share Posted March 2, 2006 The VG30DETT rods are beefy. Especially after comparing it and the pistons to other VG30 components. The crank end of the Maxima rod looks to be substantial as well. From what I have read the VG30DETT rods are the same as the VG30DE's... Nice pics... Quote Link to comment Share on other sites More sharing options...
mtcookson Posted March 2, 2006 Author Share Posted March 2, 2006 Yeah, VG30DETT and VG30DE rods are the same... actually I think the VE30DE has the same rods as those as well. Quote Link to comment Share on other sites More sharing options...
Beck Posted March 2, 2006 Share Posted March 2, 2006 VG30DETT VG30DE VE30DE Same rods, exact same part number in US. Quote Link to comment Share on other sites More sharing options...
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