Gradenko

Needajapcar, the pics are sweet. Especially like the modified standard plenum .

R32-GTS, maybe the rb20 plenum has bolts in different locations, but theres no way you're going to pull a rb25det plenum in 20 minutes. ?? Have you priced these for the rb25det? They're not $10.

rob77, I'd be hesitant to remove the plenum just to get to the injectors. Pulling the plenum is an absolute PITA, so only do it if you have to. Unbelievably the gasket between the upper and lower plenum in $85 from Nissan. I think rev210 has removed injectors with the plenum still on, so give that a go and pm him if you get stuck.

I'll put up their details for everyone to see: EFIS Unit 6/ 173 Bank St East Victoria Park Ph: 9470 1303

You forgot to mention the pumped rear guards from a gtr. *drool* I'd buy it if I was in the market.

Yes, if you've got easy access to the injectors its worth getting them cleaned and flowed. Mine were blocked even though it hadn't manifested in pinging or rough idle yet. I haven't driven my car yet so I can't comment on the difference, but I remember on SDU people were raving about smoother throttle control, smoother running and better fuel economy after cleaning injectors. I can highly reconmend EFIS in East Vic Park (as referred to me by Steve-SST). Don't know how much they charge to clean injectors but they were reasonable in fixing up a stuff up another injector place made with my injectors. I have a bunch of 25% off vouchers for EFIS that you are welcome to. Don't know if they're still valid though. What did united mean by "leak in the middle"? The middle injectors in the fuel rail leaking? Or some fault in the centre of a injector making it leak? EFIS pressure tested my rail once the injectors were back in and none of them leaked.

Craved, what part number did you buy? I remember there was a problem a year or so ago when what they thought was a 25t rotor was actually too thick. Its since been corrected, afaik. (I've got a pair of DBA4963's waiting to go on).

Cool, thanks for pointing that one out Sneeza.

Strich9ine, yeah I do. Fresh CS graduate and I'm looking for work too.

And ban multinovas. Speed cameras. Outright. Just like Canada. Oh, how I want to move to Canada...

I've got firewire, the hardware and software (Premiere) to do video editing with. Do it occasionaly for my dad (budding short film producer). Won't be pulling th firewire card out but feel free to drop around with the m-dv tape. I can dump it disc if its small enough or a spare hard drive if it isn't.

I've been thinking about it and I think Nissan went for a front facing plenum on the s13s because there isn't enough vertical room under the bonnet for a crossover pipe. You always hear about how tight it is to fit rb's are in there, so it seems likely. SR's don't really have a soft boost hit though. And the piping is ideal for jz engines with their front mounted intercoolers. (Maybe not so much on the Soarer with its side mount). Read the recent AutoSpeed article about an air to paraffin wax ic? Has some benefits over air to water. Interesting reading.

I don't mind some friendly discussion, thats why I posted it . The reason why its better is easy, the front facing plenum saves me at least a metre of piping. I should have made that clearer. Theres a pic attached showing what the piping looked like before the plenum change. Why didn't I use a 120 degree bend at the thottle body in the first place? Cause it would have increased the cost of 'cooler installation at the time (since a new bov mount would have been needed), and I wasn't prepared to pay that much when there was a chance I might change the plenum in the future. As others have explained, 1 and 2 aren't favoured. Rather, a pressure build up at the back of the plenum would tend to favour 5 & 6. I see your point about Nissan putting big money into the design of this plenum, but consider that their goals may not be the same as ours. Nissan's target was to lower the cost of ic piping and shorten its route to the factory intercooler. Nissan would have a huge R&D budget, but I'm sure they used it to lower costs, rather than even out airflow and give the aftermarket a good base to work on. It's likely that crazy rich fuel maps and dropping timing at the first sign of any real air flow was their safe guard against bad plenum design. The front facing plenum is no stranger to Nissan, look at the ca18det and sr20det. Or what about the 4g63, 1jz and 2jz? All big power engines with single throttle bodys on front facing plenums. I'm convinced packaging was Nissan's main reason for the cross over plenum. Roy, I see what you're saying re: the standard plenum being sufficient for horsepower reasons. Thats one of the reasons I kept my plenum rather move to a new design. Another benefit of modifying the factory plenum is retaining the factory runner lengths. Nissan would have tuned the runners for max torque at lower revs (as most manufacturers do) and thats likely very difficult to improve on, so its something I'd like to keep. Thats it in essence. If the thottle body was mounted flat to the front of the plenum, there would be a greater chance for air to bypass the front cylinders and pool at the back of plenum. By mounting the throttle at an angle, air is directed to the side wall and dispersed so no runner is favoured.

A lot of interesting points brought up in this thread. Volume of pipework and volume of plenum, for those who are moving to a front facing plenum for response, are the important factors. The 80mm vs 63mm comparison is a good one. Another one is the 5L+ most of aftermarket plenums consume vs ~2.75L for the factory one (caluclated, not measured, so may be inaccurate). Not to say 2.75L is ideal, it isn't, but it should perform better from a response point of a view. (Warning: Uneducated fluid mechanics ahead) I don't agree with the factory throttle body location. Runners for cylinder 3 & 4 are undoubtly favoured in my opinion. The design just seems too ameaturish to feed air evenly. I don't believe the stock fuel rail can be blamed for cylinder 3 & 4 running lean either. According to a local injector cleaner, the design seems ok and it's not as flawed as, say, one from a wrx (ej20). I had originally planned to do flow bench tests on the stock plenum to see how good (or poor) its design is, but as you said, flow benches can't be used to test plenums accurately. While its possible to the test how much each individual runner can flow, this figure means little when all 6 runners are in use. The real difficulty is in trying to predict flow after reversion from adjoining inlet tracts cause pulses along the plenum. In truth, its pretty damn difficult without megabuck instrumentation that only engine designers would have. The only thing I can do is question Nissan's design and try and improve on it. Thats what led me to try a modified factory plenum. I wanted good response with a factory sized turbo with fmic and that meant shorter piping distance, low piping volume, no increase in plenum volume and standard 60mm throttle body. A modified factory plenum would suit very well in this situation. (Before big turbo ppl jump on me, I said stock sized turbo ) I didn't have a hand in the design of my cut'n'shut (one of GTS-t VSPEC's friends made it), but it does have a bit of thought put into it. Off the top of my head: - Throttle body isn't mounted perpendicular to the plenum. It enters at an angle so charge disperses against the side wall of the plenum and doesn't favour cylinder 5 & 6 or neglect cylinder 1. - Wall between throttle plate and cylinder 1 is smoothly radiused to encourage flow. Should have the piping finished early next week and I'll be keeping a very close eye on the detonation threshold of individual cylinders. I'll call it a success if it gives a noticable increase in response and doesn't increase the tendancy to ping. Extra power is not a goal. Pic of plenum in attached. Excuse the quality, it was taken with a film camera and scanned poorly.

initialD, I'm going general admission with a few friends. New grounds are apparently better for spectating than langley, so it can't be all that bad.

In reply to myself, I finally got a pic taken. Not all that clear though. I was holding the plenum "steady" and the half a dozen beers I had before hand had some say in that. Thats looking down the throttle mounting plate. The light you can see through there is coming in the through the entrance for runner 3 & 4, which is just off the top of the frame. So what happens to air thats blasting in there at 1-odd bar? Some of it hits the runner divider and scatters, but the rest, the majority, takes the path of least resistance to low pressure goodness and ends up in cylinder 3 and 4. Horrible design.

DCIEVE, I was going to sell it for $60 on another forum but you can have a SAU discount . $50. Pic here. As long as you can mate your current throttle position sensor onto the new throttle body, you shouldn't have many problems with the ecu recognizing the tb. Fueling might be an issue though and a s-afc won't be as good as a remap.

raasclaat, I may have 1 (only) grandstand ticket for Saturday available. I'll have to confirm first though. Don't know which stand its for yet.

eriktufa, a set of 4 height and rate adjustable struts and springs (coil overs) are going to be around $3000. If you want electronic or hydraulic height adjustments you should have bought a F40 or F50, cause our cars weren't designed for that . Aftermarket work would be all custom and big $$$. If your shocks aren't worn and don't need replacing I'd pretty much learn to live with it. Any other crazy dreams we can shatter?

Thought I'd play the avatar swapping game.

Hey there. nufing much happening here tonight.

BOOSTMEISTER's right, it's not laziness. It's a combination of ignorance and illiteracy. Why does it matter? Because English is how we communicate on this forum, not teen speak or l33t speak or whatever the **** it is some people try to pass off as english. You aren't being graded on spelling and grammar, but you will come across as a dumkoph if you can't get the simple things right. Tolerance is important of course, people for whom english is a second language can be forgiven, but a lot of native english speakers need to put in more effort.

'97 Lancer MR in 1998 was my first car. Major doof. 141dB at Autosalon 2001. In its half finished state: (More pics here). Was planning on selling it to buy a R32 when some low life took it upon themselves to steal it, thrash it, crash it and lighten it of its stereo. So being without a car and having no luck finding a decent R32 (market was dry in late 2001/early 2002), I was forced to buy a... ...'93 R33 25t. My second car, still going strong and no doof this time.

Interesting plenum, summoner. I remember Phil selling them on pf for rb30's. With the throttle body, a 60mm rb25det one won't be much of a restriction up to 400hp (at the engine). I have an extra one for sale too .

The stock plenum has had sweet bugger all engineering into dispersing air evenly. It may do, somewhat, but thats more a matter orf course than design. Nissan's target was to lower the cost of ic piping and shorten its route. That they suceeded at, at the cost of an undersized 'cooler, but even air disperstion was not at the top of their list. I should take pictures of the stock one I have lying around here. The throttle body is positioned such that it blasts air right down the neck of cylinder 3 and 4. No deflectors or trick engineering gone into it at all. I'd be willing to wager that cylinder 3 and 4 running lean is the cause for a substantional number of rebuilds. Properly done, a cut'n'shut should have no problems out doing the stock plenums job, just have to take it to someone who has experience with it. If you're still sceptical, consider the number of oem plenums that are front facing log-on-top-of-runner styles: ca18det, sr20det, 4g63, 1jz and 2jz. All very similar to what a cut'n'shut ends up being (especially the last two). The proof is in the works though and Steve-SST has given mine a thumbs up, so it'll interesting to see how it'll fair.