RBceffy25

All good mate no offence taken and I’m not shitty lol. I understand everyone is entitled to their opinions however, it might pay to keep 'possibly' offensive comments to yourself. If I 'had' made it myself would you have made the same comment? Food for thought. What I meant by "pushing around 500rwhp" is that the guy I bought it from obviously had no problems with it flowing well. I love the pics of your engine bay and most of the way you have gone about your build but there are certain things I would have done differently. But I’m not about to start criticizing you for this. It’s these differences that make owner/building and modifying such a personal thing and it’s what keeps forums and discussions such as these happening. I chose to use this modified forward facing plenum as I am building/modifying on a very tight budget and cannot afford some of the more exotic items on the market. I have researched the factory modified forward facing plenum and it suits my intended build and purpose just fine especially from a budget conscious point-of-view. I did not intend to compare my plenum to either the plazmaman or the greddy. I was actually looking for info in regard to the benefits of using a much larger than standard throttle. Any way back to the question. I'm worried about the affects of turbulence as a result of interrupting laminar flow, So can anyone please tell me what the pro's and/or con's are of changing to a larger than standard throttle body?

In fact it came of an RB25DET pushing around 500rwhp I couldnt give a shit what it looks like as long as it does its intended job. Please justify 'questionable'?

whoops. and the rest.

And this? I will be using a Q45 throttle and I am wondering, what are the merits in this? I was going to buy a P/M plenum but then i came across this puppy on ebay for pretty cheap which originaly had a 90mm GM throttle but i pissed it of in favour of a newer and in better condion Q45 model.

I am also wondering about an answer for these questions? Anyone? Cheers.

UltraRacing

Sweet man, nice set-up. Get a volt meter and check your pump for sure. It should be running at about 13-13.5 volts at idle if it’s been wired correctly. I forgot to mention that it might also pay to get a can of CRC MAF/AFM cleaner. This shit works wonders. Other than that, I would change fuel filter and plugs (coppers, 0.8mm) for security and take it to a dyno to check air/fuel ratios.

Hey. When did you last change your fuel filter? It may be partially blocked. Gap your plugs to 0.8mm. Also What voltage are you running with your pump? If it hasn't been done already, you need to wire it directly to your battery with a 30amp relay in place for correct operating voltage. If you are using the stock AFM you may also need to change it. RB25DET AFM's are temperamental things especially when compared to Z32 or even R32 and don’t like to run too much boost through them especially on cold days/nights. What ecu are you running? If its stock the problem may also be a factory safe guard known as ‘rich and retard’. If you running Splitfire’s they should be fine but if you’re concerned have them tested. All in all it’s just a process of elimination but to me it sounds like air/fuel ratios are out which is known to occur around this rev range on RB25DET which tells me its running rich. I hope this may help you in some way. Cheers.

Rich and Retard. my understanding is that this occures when the intake temp is too cold (higher than standard boost with fmic usually the culprit) and the AFM defults to max air flow because the stock ecu believes ther is a large boost spike where there shouldnt be, dumps fuel, and retards the timing in order to produce less exhaust gasses to reduce boost. Only fix is turn down the boost, get aftermarket ecu or nisstune. Anybody please feel free to correct me if im wrong in any way. Cheers.

I am know expert on this but my brother is in the process of this atmo. It is do-able in a number of ways such as adapter-plate (my bro has this) or weld to shortened stock runners. depends what sort of touque curve you want and more inporttantly where you want it in the rpm. What kind of driving style/dicipline will the engine be used for?

Im not 100% but i would assume the ports and runners on the rb20 are smaller as i know for a fact nissan revised the intake quite a bit on the rb25 which uses 50mm internal diameter runners.

I have a very similar problem after pissing of a dodgy walbro (second dodgy walbro i've been through) and installing an 040 with new wiring. Runs at 13.2 volts (give or take) on idle but when engine is being cranked a voltave drop will always occur (down to as low as 10 volts) wich i think may be causin the slight hessitation to kick over. To combat this i just let my car prime for a few swconds before cranking, kinda like when you wait for the glow plugs to heat up on a diesel. Funny thing is though the standard pump and the walbro didn't have this problem. But judging by the sound of the various pumps under ther different voltage conditions the bosch really souns like it srtuggles with the voltage drop hence why i let it fully prime. Then starts instantly. I have cleaned all lines, replaced the fuel tank and filter.(due to rust because of water. the car sat in a yard in japan for bout a year befor i got it) Hope this helps in some way

Its a valid move to drop it only to raise it again with bolt-ons. A free flowing exhaust will premote better spool and response and a fmic will help prevent detonation due to high intake temuratures not to mentiong easier power with less boost as a result of cooler intake temps (intake air is more dense). just be carefull of R&R. Also im pretty sure R34's run bout 10psi stock which might have somthething to do with having the larger OP6 turbine housing. On a side note i would say that they respond to this better as the NEO cams have more aggressive lift (8.4mm in 8.7mm ex) due to its solid lifters.

Ok firstly I would always go with a well known brand name. I have personally never heard of cooling pro. Just by looking (which is inconclusive in most cases) the blitz core appears to be of much higher construction quality and the end tanks appear to be pressed, not cast (pressed being lighter and stronger). Also there is no photo of the inside of the cores, so you cant see how much metal/fins are inside each tube/bar. You must remember here that this can be a compromise between cooling, efficiency and flow but usually the big brands get it just right. It can also depend on what power figures your chasing. For example, I currently have in my possesion a Hybrid GT2 core and a Greddy spec M core and the spec M core is far superior as far as fins per inch both inside and out are concerned. However the Hybrid core will do just fine for my power figure and set-up not to mention that nearly any aftermarket core will be superior to the factory side mount core. I am now using the hybrid core with great gains. Also keep in mind that the stock R34 core is twice the size as R32, R33 and are said to be good for up to 200rwkw. Another thing is that the cheaper brands usually still need to be modified to fit (i.e cut/trim piping) regardless of the fact that they claim it is a direct bolt on. Although having said that no direct kit will fit if, for example, the car has had an accident resulting in structure/frame work of the body being slightly or dramatically shifted. Food for thought.

stangely enough i had this exact problem when i accidently plugged in coil no. 4 the wrong way. yes thats righ i put the plug on up-side-down. I know this is really f*ken stupid and believe me its the last time i'll ever work in the dark. i always carry a torch in the car as a result of this. I had just cleaned my AFM, pod, gooed and taped the coils and cleaned and reset my IAC before this without having this problem at all but the car was hunting at idle and had a bit of a miss. then i did my plugs a few days later and the problem started. couldnt work it out for a day then decided to check the obvious, that being the last area of the engine i worked on (the plugs). yes i am a noob for this. Dunno if this helps. Thanks for reading.

Thanks mate, much appreciated. Ok firstly, I assume what your saying is that when you make boost or start making boost and then back off the throttle (which initiates the BOV because the boost needs somewhere to go when the butterfly in the throttle body slams shut) your engine is stalling. Is this correct? (i'll explain more on this later) Also please explain what you mean by "It feels like it gulps in a shitload of air and it doesn’t like it" Next question. What type of BOV are you using? Is it the standard unmodified plumb-back unit or have you swapped it for an aftermarket item? And if its aftermarket, is it venting to atmosphere or still plumb-back? Depending on your answer, it may have something to do with what i started to explain in the brackets in the first paragraph.

My bad. This is the one you want: http://docs.google.com/viewer?a=v&q=ca...R5AvGD9-hF29boA

This link shows just as i have explained. www.turbosmartonline.com/index.php?id=108

Ok mate read the following carefully and study it. As far as I understand one line/hose must go from actuator to tee and the other line/hose from either compressor housing of turbo or turbo outlet pipe (the pipe that goes between the turbo and intercooler). As far as I remember (and I have installed about 4 different makes and brands of boost controllers) it must be before it goes through the intercooler as a minor pressure drop will occur through the intercooler giving inaccurate boost and false readings. Also you I think you have leave the factory boost solenoid connected or your ecu/AFM wont like it which could be why it wont allow you to make more boost due to the AFM not seeing correct boost levels in correspondence to what the ecu thinks it should be seeing from the standard boost solenoid. I know it sound like a contradiction but trust me it actually makes sense because when you install an aftermarket boost controller it runs independently without being directly linked to the ecu, AFM etc.... leave it plugged in to the loom but cap off the ports. By the way save your money and get an electronic boost gauge with its own solenoid etc as I have also used various cheap mechanical boost gauges and they are too inaccurate for a conclusive boost reading. I even went through 2 identical 'Speco'(supercheap) gauges on my own car and both read differently running on an identical engine/car setup (I assume this is what you are using). By the way your idle issue is your IAC valve. Here is the link you want http://www.skylinesaustralia.com/forums/Di...0&start=160. It’s easy as and it works. While you’re at it though I recommend you also remove you AFM and pod and clean your pod and get a can of CRC MAF/AFM cleaner. It also works nicely. I hope all this helps you in some way.

Had my car around three years now and when I first got it I used a holesaw with extension to core out my cat and the whole insides disintegrated and just simply fell out (alot easier than trying to bash it out. that’s if it’s in pretty good condition like mine was). I found that when I first did it my exhaust note changed ever so slightly (more aggressive but probably more due to gaskets constantly blowing out at the time) and boost response is slightly better and went to rev limiter fine on stock boost. HOWEVER since I have now fit FMIC and played with the boost a bit it definitely starts to lean out around 5000-5500 and above. (I’m only running 8-8.5psi due to R&R as I have a massive CAI which was causing compressor surge and R&R. Its now partially blocked until I get Haltech and tune. And yes I have cleaned my AFM, gasket gooed, taped and cleaned my coils and re-gapped to .8.)

Sweet i will take the lot! I'm in QLD Give me a txt or call on 0420755995

Malaysia will be your best bet. However If you decide to purchase from there be very careful as there is a lot of dodgy shit for sale from there. And a lot of dodgy sellers.

As far as my own personal research has shown, cefiro front strut barce an sway bar are unique and will only fit cefiro. For strut brace i use UltraRacing and for sway bar Selby.

Has the boot got all the trims/lining inside still? And also the little trims that go over the back of the seat rails?

My apologies for the multiple topics. I just had some major problems with my internet connection.