GTRNUR

Yes what Tony has said is correct. And yes you should remove the cover from your CAS and inspect it after you fit a cover and gasket/spacer. What you are looking for is the position of the trigger disc, and if it is rubbing on the optic sensor. If it is, you can carefully and gently tap the shaft back to its position in the CAS bearings where it should be positioned... so the trigger disc is central in its position in the middle of the optic.

Glad you caught it in time. I think you'll find a re-surface and some Hylomar will solve all your woes. Are you planning on doing a full tear down and re-assmelble, or just re-doing the top end? If your going to try just re-doing the top end it is still worth pulling off the main cradle and having a peek at the main bearing journels. Have a look at one or two rod bearing journels as well while your at it. Just so you can restore your confidence in the engine.

I generally prefer original parts as they fit better, rather than some cheap aftermarket thing. You can probably pickup a stock cover cheap 2nd hand from someone else that bought a clear one. You need this gasket too. http://cgi.ebay.com/ebaymotors/Nissan-OE-RB25DET-Cam-Angle-Sensor-CAS-Seal-Gasket-RB25-_W0QQcmdZViewItemQQhashZitem2eb20ef2f9QQitemZ200555819769QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories The gasket and the cover together are a spacer that goes between the cas mount and the cas. When its mounted properly it shouldnt move. You obviously need a timing light to align it correctly as well. The fan shroud is meant to pull air through your entire radiator, not just a small section in front of the fan. Larger cores have more coolant volume and when the air flow is sufficent they can lower coolant temps faster than a thin stock core. But because they are thicker cores the air flows through them less easily. So you actually need a shroud more for an aftermarket core for low speed driving than you would for a stock core. Above 80km/h the fan is mostly not in use. There is a lot more to it than that though. The thermostat of the engine, the engines ideal operating temp, the heatsync on the front of the thermally activated clutch fan, the rpm of the fan and the load of the fan itself all work together in concert to work properly. Nissan design these things very carefully and the complexity of it goes a lot further than most realise. This is why stock is best for reliability and consistancy, and also why most aftermarket/custom setups only work in specific situations. Modify something and you upset the balance Nissan created.

What you need is 1. New fan clutch (Get a davies craig one as mentioned above) 2. New radiator fan shroud 3. Timing belt cover with CAS sensor rubber seal 4. 3 bolts for the CAS sensor... not 1. All of these things are critical. 3 especially, as RB's are interference motors. All it will take is a bolt or socket dropped into the timing belt area and you will slip or break the timing belt and destroy your engine. What you have there is the downside of a modified vehicle. So many modified vehicles are mess with, without any comprehension of what happens when things go wrong... or with little to no regard for how Nissan designed them.

The viscous hubs is effective to 4000 rpm before it slips. There isnt a 12V fan in existance that can move the same amount of air that the factory fan can, and if there were they dont make an alternator big enough to drive it. The engineers that designed the factory cooling system know what they are doing. If its in good shape it works very well. Messing with thermostats messes with your tune too, so keep the stock temp thermostats unless your planning on making massive changes to how your tune works with temperature compensations. Just fix the factory setup and it will be great.

Yes I confirm this! I wouldnt consider an MLS gasket unless both surfaces are machined dead flat. Some machineshops use different tooling to shave/deck heads and blocks too. Its worth asking around to see who can do the best surface finish to the highest tolerance. Or just o-ring the cylinders and use a standard gasket and its even better than an MLS gasket.

Hylomar is an ACL product, and its a non-setting high temp silicon base sealant. You get it from supercheap auto or autobarn. Cheap as chips and worth its weight in mur. The acl product is intended for use on copper head gaskets, much like the copper spray, but it is definatly not copper.

Don't beat yourself up for having a go. There are many that wouldnt have gotten as far as you have already, and nobody gets their first engine 100% correct. A standard graphite syle head gasket will tolerate up to 0.007" of surface variation. Chances are the block was fine, but the heads are rarely perfectly square. The head being alloy tends to take on the distortion of the head gasket and block it was previously bolted too. Its called bruising, and is the main reason heads are shaved, so as to produce a dead flat surface to mate to the block. Having said that, a good coating of hylomar spray on the head gasket would have also guaranteed a seal. When you do re-fit the head, you should give the gasket a good 3 coats a side letting it tack off between coats, so its got an even shade of blue. The head stud torque will be fine, provided the block was torque plated to the same torque when the finish hones were done. So long as the bolt torque is at the recommended tension, and under the yeild strength of the bolt it will be fine. The blocks hold a hell of a lot of tension. The 1/2" studs in my engine are torqued to 110ft-lb.

Shutting down the engine immediatly from hot and checking the plugs should reveal which plug is being steam cleaned, though thats not a fool proof method, as steam cleaning requires some combustion to happen. If the cylinder doesnt fire at all, the plug will just be wet and smell of fuel. The scope will only spot damage after its happened. Having water in your oil is good enough reason to pull the head off and check the gasket is covering the water and oil passeges properly. Your going to have to do it to fix the issue anyway, so why delay... Did you do a test alignment of the gasket on the head and the block to make sure it covered the holes? What kind of gasket did you use? Was the block decked and the head re-surface before you put the head back on?

My guess is that the cylinder flame out is due to the water in the oil. What is happening is that when the engine is hot the water boils off the oil and ends up in you head and blow by re-breather hoses. Its then sucked into your plenum. The temp drop and pressure drop as the vapor enters the head causes it to condense back into water. Once there it will go the shortest path to the nearest cylinder where it will cause the engine to flame out. You can spot the issue by seeing which plug is too clean. If the grub screw on the VCT isnt leaking then its your head gasket, which isnt uncommon. Hylomar is your friend. A good spray on the gasket before torquing the head down is the only way to eliminate this sort of thing. Now the bad news... Chances are the water in the cylinders are causing a lubrication failure issue, and will be resulting in the rings scoring marks in your bores. Cylinder material particles will also end up in your oil, damage your pump, and your bearings. You need to pull the head off and have a look at the bores. With any luck you will have caught it in time.

You need to remove the circlip from the actuator arm and test the movement of the actuators without them pushing on the arm. If they dont operate identically then you should replace them both so they are matched.

As the TO4z is supposed to perform similar to a pair of GTRS's, it would be fairly safe to say it will start making boost below 2000 rpm, have a good .4 bar by 2500 and achieve full boost by 3800-4000. The right cams and head porting + tune will make this even more responsive.

No hurry... Just do a post when its off the car. Hope you dont lose anything in the floods. Water is a real pain in the ass. I had 2' of water through my workshop 2 years ago in the 100 year floods in Cairns.... Then I moved. Cheers, Ian

That makes 2 of us. Just ignore me. I read the reply wrong.

Im interested pending pictures and if you can have someone be a referee for you.

Sounds like the builder didnt re-torque after pulling the cams down to compress the valve springs. If it were a design flaw there would be hundreds of factory standard engines around with the cam bolts in the sump.

I'd be having a good look at your tune, and your EGT's. These manifolds shouldnt crack if your tune was correct for normal unleadded fuels. While switching to an alcohol based fuel in theory lowers combustion temps and EGT's, the way many people are setting up their E85 engines with higher compression means the common target afr charts dont produce an EGT that is in the safe range. Ive heard stories of melted exhaust valve guides in alcohol based fuel engines that run compression at the higher end of the scale, so it stands to reason that a moderate increase in EGT's could certainly cause stress cracks in in a manifold.

The old car vs safety factor is easy to deal with. Simply post the speed limit for the older car, and pass a law that says car manufacturered at such a year can exceed posted speed limits in x class of driving zone by xx km/h. The police(or privatised speed monitoring) can still have their flash for cash camera vans on the side of the road and photograph everything that exceeds the speed limits. And if they are able to read the number plate they surely should be able to identify the make, model and year of a vehicle and send out the appropriate fine(or not). They 'could' even allow for modifications to allow improvements to older vehicles so they are certified for higher speed driving... such as modernised hotrods etc. A suitable testing system can be devised and a sticker stuck on the windscreen. Its that simple! The reality is though that government would rather see everyone driving a prius and having no interest in motoring or motorsports at all. (yet the irony is that ALL the safety developments and technology developed in the modern car was developed initially on the race track). I wonder sometimes if there is some ajenda behind the closing down of so many motorsport facilities, and the constant rejections for construction of new ones. Shame Peter Whelan doesn't speak with a great deal of confidence. I think he would be torn apart if he were put in a debate with one of the anti-hooning extremist spokes people.

Nitto's new slogan for their oil pumps.... "Engineered to pump engine components... not just oil!"

Price drop $800 + delivery, or will trade for other parts that will suit my R34 GTR. Im after poncams and some gear to give my fuel system a boost.

Bump!

What you have described is very similiar to how I was 10 years ago. I'd platoed at a lean 76KG, and was on 6 meals a day + 3 protein shakes a day and creatine when training. I couldnt eat anymore as I was already eating when I wasnt hungry and hated feeling bloated. I'd do light weights and light cardio on even days and heavy weights on odd days and had sunday off. I was nearly triathalon level fit, and was strong for my weight but I wanted more size and had hit the wall growth wise. As it turns out I was doing two things wrong for my metabolism. I was naturally a skinny person, and I was over-training. Also becase of my fast metabolism my fat and sugar intake was way too low, so most of what I was eating was being used as fuel, instead of building size. I now dont do any cardio at all as it tends to immediatly put my body into a carbolic state, and I weight train 3 days a week at the most. I try and do a fast warm up using light and medium weights, and then step it up to my limit. And finish with a set of lighter weights to cool down. Im not using any protein or creatine this time, and have been just eating more lean chicken and eggs instead. 3 meals a day is all. And then there is the part that pisses my girlfriend off. I eat a huge amount of icecream for desert every night or just snack on it in the afternoon. I know this probably goes against what everyone says is good for you, but it hasnt made me put on an ounce of fat and has allowed me to make muscle growth gains. I now bench press 20Kg more than I did 10 years ago, and my stand free weight bicep curl is 10 KG off what I was doing 10 years ago as well. I have had to be careful with much of my arm training though as the reason I stopped training 10 years ago was that I tore the ligaments in both wrists when training too hard. So in the end doing a lot less has helped me more. Im still miles off where I want to be size and weight wise, but its been so much easier getting there this time round. Anyway that might give you some idea's... so I thought i'd share. Cheers.

Light grade on the end of the stud that goes into the block, and on the idler bolt thread. The wavey locking washer under the nut and the correct torque spec for tightening the nut do the rest. Nissan know what they are doing when they design these things so there is no need to over think, or try and over engineer something that is already thouraghy tested, designed and approved by teams of engineers. Everything you need to know is in the manual.

Have you had a close look at the hone patern on the cylinders? It seems to be a little all over the place. Its possible the hone is responsible for the rings not bedding in properly, resulting in a lack of lubrication that then caused cylinder gouging. Have a look for more information here: http://www.hastingsmfg.com/ServiceTips/cylinder_bore_refinishing.htm

To install them properly you do a trial fit with no shimms installed. You then need to measure the distance between when the cam bucket and the cam at 0 lift so you can work out what thickness of bucket shim to use. You have to rotate the engine over by hand with both the cams installed when doing this, so you can measure from the middle of the back of the lobe to the cam bucket. Once you know your cam clearances for all 24 valves you can order the appropriate thickness shims. Jun cams use a recommended 0.3mm intake and 0.33mm exhaust clearance. There is a few tricks when installing them too, such as using wet and dry paper to trim the shims up precicely, and also to take the sharp edges off the machined edge of the shim, so that it fits better into the back of the bucket. The importance of getting this right makes the difference between having an optimal setup, having a less than optimal setup that is noisy like a tractor, or having a valve not seal against the seat which will result in a burnt valve seat and head damage or worse.