chad bob

I'd like to work on the only fault i can find with my VQ30DD powered M35 Stag. It's just too damn quiet! All of my previous cars have had factory exhaust systems that let some rumble and snap crackle pop filter into the cabin, this made them easy and fun to drive. The Stag just 'wooshes' along with nothing but the tire noise to allow me to judge the road speed without a glance at the tacho. What I'd like to do is moddify the exhaust system so that I can at the very least hear some of that gorgeous rumble that I can faintly detect on take off. I'm not out to wake the neighbors nor change the exhaust tips, I just want to hear my motor! Now I was wondering if anyone has replaced the back silencer with anything less muffled? Does this allow more rumble to be heard or does it just cause droning? I was trying to avoid having to replace that massive 'coffin' muffler mid way down the exhaust line but if a back muffler swap causes droning then I may have to attack it's fat ass.

That sounds like a good idea, in the US they sell Direct injection cleaning kits with a spray for the manifold and a fuel additive. As far as the crank case vent, I'm going to install a catch can to take care of that.

Sounds good, write it up in my Di motor thread, I'd be glad for any thoughts. Crap! I thought that the 30 and 35 had the same bore with a longer stroke, ah well not that it matters.

I think VQ30 and VQ35's are only differentiated by the Direct Injection heads on the VQ30 and the extra stroke length of the VQ35. The bore dimensions are the same on both motors. I think the VQ25 has a smaller bore and stroke than the larger motors. In the future I want to put a VQ35 intake on my motor and also some aftermarket VQ35 headers.

I timed mine with the I phone 6.5 sec is rather impressive for a big wagon, my major gripe with the VQ30DD is that it has little torque below 3000RPM, the VVT kicks things up at 3000RPm and then you start going, but I found that the VQ25DET has balls from early in the rev range, big bonus.

It might be. -On long cruises with only a couple of hills and me in 'cruise mode' it gets 8-9L/100km -This weekend I drove up north, I was in 'lets just f***ing get there' mode and there were a lot of slow buggers around on steep windy roads so a lot of foot flat up hill passing (these VQ30's actually get up and go rather nicely) fuel usage = 12-13L/100km -Around town commuting to work etc I get 10-11L/100km Compared to a stock 250TRS the seat of the pants meter tells me that the VQ30DD isn't really that far behind on the performance scale they get to 100KPH in about 7.5Seconds, what does the VQ25DET do the ton in?

Hey guys, I was just wondering if anyone round here has a 300GT or 250GT V35. Reason I'm asking is that they're Dierct Injection and like most direct injection cars on the market (including my stagea) they may be in the process of or already on the way to fish town. So I have been hearing a few complaints recently concerning 'Gasoline Direct Injection' engines, particularly concerning vehicles from Toyota, Mitsubishi and Nissan. GDI has become rather popular in late model cars recently, notably the Mitsy 'GDI' and Nissan 'NEO Di' which seem to be the most prolific of the GDI vehicles, european examples are the VW 'FSI' system and also Opels new GDI system which is now widely used on late model vehicles without advertisemsnt. Now the complaints are mostly concerning poor fuel economy and multiple sensor failure with expensive repairs. This is strange because amongst a notable increase in power over similarly designed SFI (sequential injection) and Multi point injection motors, GDI motors usually have a rather impressive factory fuel consumption rating which makes them rather attractive to buyers. These buyers are often disappointed when they get to the pump with their new car only to find that it's been sucking fuel like a v8. It is rather hard to find information on why these NEW cars are costing so much to maintain and using more gas than expected, the funny thing is that performance also drops rapidly as the fuel consumption rises. Instead of providing an explanation, car companies remain tight lipped and owners get fed up with mechanic bills. So given the listed issues: -Poor fuel economy. -Decreased performance. -Injector and sensor failure. What is going on? What seems to be a constant in all examples is that problems start occurring once the vehicle millage passes 60,000Km. I discovered this while trying to research information on the VQ30DD motor in my Nissan, all the info I could find was in Japanese, but I did find the above information relating to GDI vehicles in general and also from personal accounts of friends with GDI vehicles. So I thought that since my car was GDI and was also passed that 60,000Km milestone, then it must be showing signs of whatever ailment has been plaguing other GDI motors. I thought that since the difference between GDI and MPFI motors was on the induction side, I would start there. It didn't take long to find the culprit, in fact as soon as I opened the intake manifold it was all too obvious.... SOOT everywhere! it was like black snow coating everything from the port side of the throttle butterfly to the valves, it was 1mm thick in places and not unlike the oil residue found inside the crank case of an old 2stroke lawn mower. This was a shock and totally not on for a car that was other wise in 'as new' condition, it took a can of degreaser and a water blaster to get the manifold back to 'as cast' condition, I then set about looking for the cause. The cause too was rather obvious, modern engines are being fitted with any manner of emission reducing gadgets, the most popular being the classic rocker cover vent breather and the horrible EGR or 'exhaust gas recirculation' system, both of these are designed to 're-burn' oil vapour and un-burnt fuel that would otherwise be vented into the atmosphere. When used in conjunction, the EGR and rocker cover vent supply both dense and water rich fuel soot and oil vapor back into the intake where they mix to create that lovely sooty crud, most of which goes back into the engine harmlessly as it's supposed to do, but much of it winds up stuck to the walls of the intake. Now in a normal SFI MPFI (sequential, multi point fuel injection) fuel is injected into the intake piping right behind the valves, 'Sequential' systems are designed to only inject when the valves are open, but there is still deflection and fuel vapor ends up joining the EGR and Rocker cover emissions back up in the intake, this is good because the fuel mixes with the vapors, dissolving deposits and making them less likely to settle. Of course since GDI engine injectors are inside the combustion chamber, on the other side of the valves, this means that there is nothing to stop the buildup of deposits, hence the GDI intake becomes more and more choked until the motor starts running rich and eventually large chunks of 'crud' become dislodged and end up passing the valves and become the proverbial 'spanner in the works' and this stuff does buildup into rather hard little lumps in places which wreak havoc on O2 sensors and injector nozzels. There you have it, the cause of our problems, since the car companies dont care about cars out side of their warranties, car owners are left scratching their heads and local mechanics keep this to themselves because business is booming! The only solution is, as soon as you notice your new ride becoming more thirsty, find a friend who knows motors relatively well or talk to your mechanic and ask them to check your intake once every 20,000Km or so as a standard servicing procedure. My car was not noticeably less powerful but it was using a little more juice than expected, hence my adventure into crud city. If you don't want to pay extra for an intake clean on every second service, there is a way of making your GDI vehicle crud free for life! Have a catch can installed on your rocker cover breather, this is a tank or 'can' installed in the line linking the rocker cover to the intake, vapors passing through the tank settle and this is where the oil deposits remain, leaving only clean dry air to enter your intake. In many cases this will only reduce the buildup slightly as there is still the deposits from the EGR valve, to fix this, I found an old exhaust manifold gasket and trimmed it down to fit the EGR pipe flange so replacing the original gasket seal, this creates a 'blanking plate' that effectively prevents the EGR from functioning but allows you to leave the EGR plugged in so that the ECU doesn't pick up any errors. These procedures will keep your intake crud free for life and will only slightly affect your vehicle emissions, the extra emissions produced by removing your EGR valve will be offset by the fact that your car will now run cleanly and efficiently without sucking down loads of fuel and smoking as the engine over fuels due to reduced breathing. A friends Mitsubishi 2000cc RVR was using 16L/100Km on average, the intake looked like a smoker's lungs when I got it off, the original 45mm intake was nowhere near that in diameter due crud, go figure.

Heh, yours does look like the evil twin with that body kit.

You got it, floats on watter like oil so it has to be lighter

Throw a 10mm socket in a cordless drill and you can have the door in pieces in 1 minute flat. It's super fast and easy to do, the whole fiddling session took me 5mins max and my window has been working for weeks now. It's worth the annoyance and a shite load cheaper than a new motor.

My power window on the drivers side stopped working too. If you pull appart the motor yiou will see that the springs on the brushes are too slack so the brushes are no longer running on the armature. Pull out the rotor and bend the brushes in, then re-insert the rotor and the window should go fine.

I was working out weight distribution / corner weighting on my track car a while ago and if you want to work out wet kerb weight you'll find that the Specific gravity of gasoline is 0.739, so that means that a litre of gas = 0.739Kg, so it's 25% lighter than a litre of water. So on a full 80L M35 tank you'd be looking at 59Kg

Hiya all, about 5 months ago I bought my first stagea. it's a 2001 M35 300RX (VQ30DD) with 70,000Km down, as I understand it you still can't get this model through compliance in Australia, too bad really it makes a great middle ground between the 250RS and the VQ25 turbo model. I'm a design engineer by trade based in Auckland so I'm the sort of guy who likes to pull things appart and fix my own problems before I take anything to a mechanic. So far I've found one or two issues with my wagon and managed to fix them in the shed. I'm keen on learning more about these wagons and sharing my own experiences of living with and maintaining my ride.