Rudi

I don't expect that much difference against the stock manifold on a bone-stock engine. On a highly tuned engine the power increase could lead up to 10% due to the shorter inlet tracks, improved velocity stacks and huge well shaped plenums. The inlets for the plenums are no less than 70mm, I tried to make everything as big as possible. I could make the manifold smaller for lower powered cars though, but an engine with ITB has no idle issues from a large manifold plenum. I think I can make it work with top feeds, to be sure I will take a look once everything is back in place. The PVC reroute can work, all I would have to do is weld 2 hose adapters to the intake manifold covers. Instead of doing the PCV reroute I would personally fit a high mounted oil catch can above the exhaust cover, lot's of space for that with this manifold ;) The plenum could be made from carbon fibre, the stock plenums weigh about 1550 grams per side. That includes the flanges and bends that hook up to the ITB's. Those cannot be made from carbon fibre, so the only weight advantage may come from the 'tank' itself. At best this may spare 800 grams for both sides. But it is something I intend to develop over time and depending on interest perhaps for this engine too. The advantage of using carbon is that it requires far less labor and ridge free shape as there is no overlapping. This manifold saves about 8kg's from the engine's weight. The Jenvey ITB's are also much lighter than OEM throttle bodies. The 2 stock TB's weigh 900 grams without hoses or linkages. The 6 Jenvey ITB's weigh just over 1000 gram, including all linkages! I am currently also designing a manifold very similar to this one, but far less complex with just 2 TB's fitted 'sideway pointing' like on the VR38dett. I'm going to roll that one on the dyno too. - - - Updated - - - I don't expect that much difference against the stock manifold on a bone-stock engine. On a highly tuned engine the power increase could lead up to 10% due to the shorter inlet tracks, improved velocity stacks and huge well shaped plenums. The inlets for the plenums are no less than 70mm, I tried to make everything as big as possible. I could make the manifold smaller for lower powered cars though, but an engine with ITB has no idle issues from a large manifold plenum. I think I can make it work with top feeds, to be sure I will take a look once everything is back in place. The PVC reroute can work, all I would have to do is weld 2 hose adapters to the intake manifold covers. Instead of doing the PCV reroute I would personally fit a high mounted oil catch can above the exhaust cover, lot's of space for that with this manifold The plenum could be made from carbon fibre, the stock plenums weigh about 1550 grams per side. That includes the flanges and bends that hook up to the ITB's. Those cannot be made from carbon fibre, so the only weight advantage may come from the 'tank' itself. At best this may spare 800 grams for both sides. But it is something I intend to develop over time and depending on interest perhaps for this engine too. The advantage of using carbon is that it requires far less labor and ridge free shape as there is no overlapping. This manifold saves about 8kg's from the engine's weight. The Jenvey ITB's are also much lighter than OEM throttle bodies. The 2 stock TB's weigh 900 grams without hoses or linkages. The 6 Jenvey ITB's weigh just over 1000 gram, including all linkages! I am currently also designing a manifold very similar to this one, but far less complex with just 2 TB's fitted 'sideway pointing' like on the VR38dett. I'm going to roll that one on the dyno too. BTW I can't edit my posts?

Thanks for the thumbs up everyone:thumbup: I'm quite happy with how it worked out so far, just the few small leaks and the noisy valve lifters hold it back now. I'm searching for replacements for the lifters now through my old stuff. I did want to test the manifold as a full OEM car at first. However, the noisy lifters and a couple of other small vacuum leaks held me back. I found that someone in the past had also installed very primitive bleed valves I was kinda worried they had made mods to the upper manifold as well. I decided to fix them along with the installation of this manifold. The car will later be rebuild to full OEM state.

- - - Updated - - -

An idle block was made for the AAC unit to attach to and links with the unit underneath the manifold. Eventually looks like this along with custom made hard pipes. With all parts fitted and the wiring harness modded to fit the engine fired up instantly. I did have trouble getting the idle down. I found out yesterday 3 welds cracked and need looking after. Other than that, I'm pretty happy with it. Now this thing will be seeing the dyno once all the problems are sorted out. I don't have a date set but I'm hoping within 2 weeks. After that, the stock manifold will be tested in the same way to note the difference. As of now, I can't offer this as a production part and I guess I need to become a trader here on the forum first. So for now, this is just scientific research LOL. I'll keep this updated. -Rutger

Some of you may remember I made an ITB setup for the vg30det engine 3 years ago. At that time, I also planned to make one for the vg30dett so I bought an extra set of 45mm bore Jenvey ITB's and this winter I started working on it. Because of the little space underneath the bonnet and the masses of hoses, wires etc. I needed to have an actual 300zx to test fit. A friend offered me his 300zx, it's an old one with 234.000km on the clock (even original engine) and it needed a timing belt. The engine runs OK but at idle wasn't very happy. I found some leaking hoses but they didn't really help after fixing, eventually I noticed the engine is consuming oil badly and probably makes low compression on at least 1 cylinder. The valve lifters tick like hell and I'm in the process of doing something against that before the car goes to the dyno. Will be one of the last trips this engine will make. Now we all know how complicated the OEM manifold and fittings are. The valve covers aren't really helping either. I decided to remove the large raised sections and weld in a new plate. The baffles were fitted back in (no pics). The coils were modified to sit lower and welded/bolted to the exhaust valve covers. I also made a custom oil filler. I removed some material from the base of the OEM lower manifold for a cleaner fit. The pipes were than welded upon. The exact angle etc. took long calculations and test fittings so I keep those to myself. The flanges were welded on and the ITB's could be mounted. Further test fitting of the Jenvey velocity stacks and clearance underneath the hood. Clears no problem. An idle collection manifold was made underneath the manifold, all copper lines with brass fittings no cheap ass hoses that can barely be used in such short bends. The complex plenums took 2 weeks to design and cut/weld. In order to link the cylinder banks I made a copy of the Jenvey OWK unit that pushes one wheel outside to line up with the other.

Late update. The fuel rail is a custom job, based on 16mm tube with a 3mm wall. The tubes were cut to size on a lathe and the holes drilled to exactly 108mm (stock vg30 cylinder centre distance). I had to weld pipes with a small angle as the Aeromotive FPR with the swivels was just a bit wider then the fuel rail ends. The wled on fittings point exactly forward though. The feed line comes from the front of the rail through 2 180* swivels with braided hose. The shop was out of stock on them, should be getting them next week. The water pipe leading to the interior heating don't fit correctly anymore, have to cut it 2cm shorter and weld it.

I have never driven a 300zx without the vtc and these cams. But if the cams are well setup with adjustable sprockets there should be no problem with these 260 and even the 270 cams.

The Tomei solid lifter procams require disengaging of the vtc. You can leave the stock pulley and solenoid in place but they won't do anything anymore as the oil passage through the cam is blocked.

At first I wanted to use the stock ones. However, there's 2 problems with them. First, they use a hose coupling for the injectors, both use barb style fittings. The new top feeds require a press-on fuel rail. Second, even if I got the stock rail to fit, the stock rail hangs on the injectors and therefore has no brackets. It would be very hard to weld them on since the rail is soo thin. I want to solve this by making a bunch of 11mm ID stainless pipes that slip over the injectors. The fuel rail will be built by either a square or round tube and welded on to the on the 6 pipes. The new rail will be much thicker and easier to weld brackets on. I will have to get them welded by an expert with backing gas to prevent those nasty 'burnmarks' on the inside. Turbo's are Porsche 996 should be good for at least 500rwhp. Engine has JE pistons/Eagle rods/ Tomei 260-10.25 procams custom manifolds 3" exhausts ATS carbon metalic clutch etc..

The manifold is not far from being done. Just need to make a fuel rail and vacuum ports;

Making more progress. The lower manifold has been tapped as well as the plenum floor. I had to cut small amounts from the sides of the stacks to clear the bolts. I could have build it so that the bolts would have lead through the stacks themselves and bolt it to the lower manifold, but this would have ment that the other 2 bolts for each TB had to be torqued down first, resulting in uneven pressure. The 'wheels' that you see up front link the 2 banks together with a steel wire, for a perfect synchronization of all 6 TB's. The aluminum plate is fitted with bronze bushings. Short video of how they work;

Slowly making progress. The lower manifold still needs to be tapped for the TB's to fit upon it, but the upper plenum is about done and I will be taking it to the welder this week. Making the plenum fit to the plenum flange, 5mm thick aluminum. The ground plate was 5mm too but I decided to double it's size for added strenght. The steel plate is 10mm thick and fully bolted to the flange avoiding warping during the welding process. It sits of center but gives a general impression of how it will look like. 2 Apexi bov's will be fitted to these coldpipes. This is one of the 2 exhaust manifolds I was working on, taking up much of the time for the plenum.

This might be a helpfull topic for people who want to build Tomei solid lifters and solid lifter profile cams. I've been working on these for a while and found several problems on the way that made the setup very difficult, and therefore worth explaining. I'm Dutch so please don't mind my spelling:slap: I'll start with some general info on these cams. The Tomei procam solid lifter cams are considered the best for the vg30, ca18 and rb20. This is cause the stock hydraulic valve lifters are replaced by lightweight (about 40% less weight) solid lifters. The weight reduction allows for a faster opening and closing rate and therefore more lift overall over the opening period. The problem with these solid lifters is that they require a clearence setup with shims that are sold by Tomei. This is a picture of a solid lifter and 2 shims. Notice how thin the walls are, all part of the weight reduction. The shim slides over the lifter to prevent it from coming loose. A comparison picture of a stock intake cam and a procam 260* 10,25mm lift. Notice the smaller radius of the cam. Stock is 32mm, Tomei is 29mm. Tomei designed their cams this way so no head grinding is required. The solid lifters are therefore also 1,5mm taller then the stock hydraulic lifters. It is said that decreasing the base circle of the cam may weaken the cam, but this only applies when the base circle is made smaller then the cam 'stem' itself. As you can see, this is no problem as the 'stem' is about 28mm. Tomei sells shims ranging from 1,70 to 3,00mm in steps of 0,02mm. The size you'll need depends on how old your stuff is and if your valve seats have been regrind. The intake cams require 0,45mm and the exhaust 0,38mm clearence. Why the exhaust requires less is not known to me. The clearence is quite large, most engines are somewhere in the 0,15-0,20mm range. The profile of the cams however allows for a cushion that brings the lobe smoothly in contact with the lifter to avoid wear. Since Tomei allows for just 0,01mm difference in clearence from the given values it is important that you use feeler gauges in steps of 0,01mm for a correct measurement of the clearence. I bought these from a Dutch store on the internet; Stuff that influences the clearence I performed several tests to make sure there are no differences. But there were. Temperature At first I took the clearences with the engine in my garage with subzero temperatures (-2* C). Next I took the same head in the living room (17* C) and let it warm up for a while. No less then 0,05mm increase in clearence was found. Since most manufacturers rate their parts to be measured at shop temperatures (around 17* C) I decided to perform everything in the living room. Head bolted or not? When one of the heads was bolted to the block I noticed a clearence increase of about 0,01mm. Not much but I think it's better to perform the tests with the heads on to be 100% sure. The head studs were ARP and a Tomei steel gasket was used for the record. Cam bolted to the head or not? With one of the cams fully bolted in place I found no difference in clearence vs if the cam was not bolted and pushed in position by hand. So don't bolt the cam down, it'll just wear out the bolts and head. Tomei sucks! Don't think just cause they're Japanese they take their work as serious as many Japanese car manufacturers. A friend of mine had been working on the solid lifters before and over and over he got different clearences. I found out why. At one moment I was testing if the clearences measured one day were the same the next day, with 2 different lifters with the same shims. They weren't, but in a particular way. One valve had 0,01mm added clearence, the other 0,01mm. What was wrong was that the lifters appeared to be of different sizes, no less then 0,07mm difference was found in between the largest and smallest. Here is a sheet I made with all sizes and a close up of the caliper; What I recommend you to do is measure each individual lifter and sort them to size. As you can see in the pic I used a caliper with 2 shims stacked, one placed correctly and the other with it's back against it. This works very well and avoids differences between recordings. A micrometer works even better but I didn't have one. What shims? A new head will most likely use thicker shims then a used head. One new vg30dett head I measured had almost identical clearences for all valves and required shims of around 2,68mm for the intake and 2,75mm for the exhaust. However, due to the large variations in lifter height it is important to take this into account for ordering shims. My own head with grinded valve seats required slightly smaller shims, ranging from 2,44mm to 2,70mm. To make correct measurements you must use the thinnest feeler gauges you have. However, this requires a range of shims to be used. What I reccomend is to order 2 pieces of the following sizes; 2,30mm, 2,60mm and 3,00mm. Unless your seats have been ground excessively there should be no valve deep enough to go beyond the 2,30mm shim. How to measure clearence I do not recommend the use of moly lube and other fat substances, regular oil works much better and can't influence the recordings since it flows much easier. The clearence should be measured with 2 lifters at a time for each pair of inlet/exhaust valves. Ensure you use 2 identical lifters and shims. Push the cam in position by hand with the lobe facing upwards. If a feeler gauge of 0,07mm slides in very easy but a 0,08mm with a bit of a push I note this as 0,075mm. Make a sheet and record each clearence. Note what shim was used and what size the lifter was. You can use lifters of various sizes to compensate for any large fluctuations between valve pairs. Why not cut the stems? SPLparts (where I bought my setup) recommended 24 3,00mm shims and have the valve tips shortened by a shop. However, there are 2 reasons why you don't wanna do this. First it takes a lot more time, and due to the complications thanks to the various lifter sizes the mechanic has to work hours to make it all fit. And you're paying all the time. Worse, a lazy mechanic may swap lifters and upset everything. If he grinds the valves too far they can be thrown away. The other reason is that grinding valve stem tips reduced the strenght of the valve. You really don't wanna have a dropped valve. My shop did not want to grind my valves as he needed to remove almost 0,50mm on some valves. Hope this helps. I will be trying to update it with more info, mostly on the cam profiles of stock vs procam. -Rutger

It's not really worth it. The vg30det is in fact not as good as the vg30dett. It's in the heads, the vg30dett uses a way better port profile on both intake and exhaust. However, the round exhaust ports on the vg30det allow easier fabrication of a custom manifold, since it's not required to press a round tube into an oval shape. This improves airflow as there's no diameter increase. The vg30det uses a different engine mount on the turbo side, like the Z31 turbo, the compressor entrance interferes with it. So Nissan moved the mount further up front and the cars these engines came in used different subframes. Even with an intercooler it won't be such a powerfull engine as the vg30dett. If you made a custom exhaust manifold you could push the turbo further to the firewall increasing airflow in the manifolds, but to be honest, it's alot of work and it's not really worth it. The stock intake manifold is way better on the vg30dett as well, unless you want to run 9500rpm ;)

Your stuff sounds mean:eek: I would have made the shafts in line though but you'll probably never notice the difference.

Jenvey describes a way which involves an airflowmeter, probably much like a carb tester. The idle and test takeoff points must be welded onto the runners yet, but since the fuel rail isn't complete either, that will go together. It's important to keep the vacuum hoses as short as possible or they will have to be made larger in diameter bringing it's own problems with it. I will be using a MAP based system with Tomei 260* 10.25mm procams. This won't do the idle behaviour any good but it will make up for a responsive engine:hyper: Will also prevent the problems with the AFM vacuum testing since no plenum is required. Can't wait to hear it rev without the plenum on top:eek: I also junked around 15kg from the lower end with the forged internals, carbon clutch and lightweight pulley.

Update on this one. Felt it was time to make some serious business of the intake manifold. Here's some pics of the progress so far. The plate was bent in all directions (shitty job) to avoid additional welds. The bends that form the sides for a smoother airflow path started life as 90 degree welding pipes, 3mm thick like the rest. These were cut in 4 pieces by hand with a figuresaw. I needed just 2 full bends to complete all 8 corners. The bends have a radius of 51mm, outer diameter 46mm. This model allowed the closest clearence along the velocity stacks. The inlets on both sides will be cut under a 65 degree angle and fitted with a 70mm entrance TB flange like adapter plate, connecting to another flange on the cold pipe. This is al done in order to keep a low profile for the hood. I could have used a straight design, but that would have required an oval entrance to keep surface up. Bending a round tube leading to it in an oval shape would have looked bad and upset the airflow (the coldpipe should be largest at the plenum entrance, not way before it). These are the TB's with just the full throttle arms sticking up. I may have to remove them as they stick out into the plenum floor. They're not that important either since they close the way after the 90 degree angle, so at WOT they will never be touched. This is the Jenvey spindle extender kit. I use it on the passenger side bank, I ordered extra parts for the other side (which uses a much longer shaft) but they have been on backorder for about 3 months now :rolleyes: The system will be bolted to the plenum floor for additional strenght. The aluminum thing bolted to the TB side houses bronze like bearings but it needs to be shortened, like with all other stuff with these TB kits, everything is DIY. Both banks have the operating wheel and the levers connect the banks for a perfect synchronization of throttle opening. The 3rd lever connects to the regular throttle cable. This is the lower plenum after welding and skimming the surface by a shop.

Thanks for the offer but I live in the Netherlands so I prefer a LHD car :D This won't fit upon a vg30dett. Maybe it would fit if you enlarge the dett ports at the heads but it will be alot of work and the flange area will be reduced increasing the chances of leaks. vg30det's are easy to come by. The sell for around 200-300 pounds for a very decent engine in Japan, an importer would be able to source one. Point is though, the exhaust manifolds won't fit unless you have them custom made. A friend of mine is making a set for the vg30dett, if he's done you'll see some pics of those soon as well :nana2: He's trying to keep a low profile so it might even clear the stock hood, with dual plenums as well.

I plan to put it into a Z32 slicktop 2 seater, and undo it from any not needed stuff for the track. I hope the bonnet does not require that much modifications ;) _cj_ :rofl:

Oh and the engine came from a Cima I believe, but it was also used in some of the later Z31's.

I paid 1440 euro's for the velocity stacks, the bodies and levers/springs and the TPS as seen in the pic. Since Jenvey is British, you'll probably pay somewhat less. I'm using Blitz 660cc top feed injectors, if I cut the 3 original 8mm mounting holes on each side next to the bodies a billet fuel rail can be fitted. Small extension tubes will slip over the injectors and into the fuel rail due the injectors being quite deep into the manifold. The vg30det has an identical lower end to the vg30dett. It has the same model heads with the same valvetrain and cams, timing belt etc. However, the inlet ports are larger but not that nicely shaped as opposed to the vg30dett, though I think that the short bend from the port into the valve seat is less sharp allowing for the air to stay attached better and not slam away along the valve. The exhaust ports are round which is good thing since it is not neccesary to 'oval' press the exhaust pipes, allowing a cleaner path. The water temp meter is fitted into the head, the vg30dett has the same provision but it is not machined. The bottom end has some small bolt/press on differences. The water pump and pulley are different, so is the crank pulley. The oil extension is not used since the oil filter is directly attached to the engine. The 2 holes normally plugged on the vg30dett next to the oil inlet from the filter have check valves.

Just got them last week, they are made by Jenvey, 45mm bore, 30mm tall. They're very compact and feature an ingenious lever and spring system which is very compact too. The levers currently face up but the bodies will be turned around so they face the engine, clearing the plenum floor for a low profile. The 2 banks will have to be preciously matched and I have yet to find a way of doing so. Some modifications to the lower manifold are required. Typical add on is the increased runner lenght, up by 50mm since the original plenum floor also serves as the runner end and the extra 30mm and 19mm from the velocity stacks + the new plenum floor (5mm) lengthen the system. This is in fact an improvement over stock since the stock system is extremely short. Nissan tried to compensate with a variable plenum design for the vg30det. The engine will see 2 Porsche 996 turbo's along with custom manifolds. It already has ARP head studs and Tomei steel 1.2mm head gaskets. I will probably also have the low end done with forged JE pistons and Eagle rods. Cams may be used if required. -Rutger

Well then entire axle needs to be removed from the joints, so I already done that...

What do you mean with a fly press? I cannot find a point to get a hold of the axle, just a ditch for the c-clip :( .

I have a problem with my TT rear suspension, the driveshaft refuses to leave the hub. It's stuck. Yes, I removed the 36mm nut, and then used a press to apply pressure on the driveshaft. After 3 tons of pressure still no movement. Anyone know how to solve this? And is this a typical 300zx problem? I had no problems with previous z32 NA and 200sx driveshafts, that use the same hub. It's not so bad if the driveshaft is stuck in the hub, as long as the axle can be removed from the joint on the wheel side. But this is stuck too. After I removed the bootband's side c-clip (as seen in the pic) the axle did allow some play towards the hub, but not further back. The manual is not very clear about it, just saying the joint cannot be overhauled. Is there a clip on the other side as well, and if so how do I remove it? Thanks, Rutger