mokompri

by definition the word increase is wrong though, relative to a non insulated type, it simply maintains the velocity it has - but i get your point yeah when you heat water molecules, or any molecule for that matter, it vibrates and moves apart from other surrounding molecules (lower density), the more you heat it, the more it vibrates. 0 degress kelvin which is the lowest temperature, is when molecules stop vibrating all together, thats why you cant go any colder by definition - it has nothing to do with the speed/velocity of molecules through space, its a stationary vibration in a way. what happens is, that you get a different viscosity, and a lower viscosity fluid will flow thinner and faster through a cavity, BUT this is verryyy different to how a gasses work. viscosity doesnt apply with gasses, it doesnt exist. a gas with a pressure above atmospheric will expand until it either fills its space, or equalises with the pressure surrounding it ie atmosphere.

mmm im really against that sort of plenum modification. plenum design is very important for flow and even more important for cylinder to cylinder distribution. by changing the point of entry i would imagine all the design work that went into the plenum is out the window. another thing is, i was told the rb25 plenums have runner dividers between them in the plenum, this would further restrict flow with a side entry, where they were purposeful for distribution between cylinders in its stock entry point. the biggest problem with uneven distribution is when it comes to tuning. the tuner will only see the net average a/f ratio of all 6 cylinders, whereas some cylinders may be running lean and some running rich, and bang you blow an engine because you think a/f's are ok but there way off. also, just days ago i was at a workshop and saw a 200sx with an rb25 as well, same plenum mod had been done with theres as well. rb25 with a gt30 turbo and only managed a measly 245rwkw ! the turbo is capable of 300rwkw, that was at 18psi though but its still off the mark by quite a bit other then that, nice work !

a gas with a higher temperature has a higher pressure for the same volume though (3" pipe) and thats what causes back pressure, so reducing its temperature will reduce its pressure and thus you should have less back pressure. im pretty sure kinetic energy and heat energy are seperate at the molecular level though. heat > excitation of electrons/changing of electron orbit, kinetic > movement of the atom as a whole. so heat doesnt affect its kinetic movement directly, unless i got something wrong there? the speed of the gasses will be a result of the volume to cross sectional area of pipe relationship. the drop in speed will be because there is less volume in the denser gas to go through the same size pipe. its mass we want to move not volume. think of it this way, a 3" pipe will reduce exhaust gas speeds because of the larger diameter over a 2" pipe, but we know which one gives more power and less back pressure. speed isnt really a governing factor in removing gasses from the exhaust, its mass ! move more mass, you have less restriction

does the PFC's boost control setup have configurable duty cycle maps to control boost ? if it does, then you could simply hook up the PFC solenoid in series like the jaycar IEBC setup, rather then in parallel, and then effectively have an electronically configurable version of that valve you are trying to implement, to avoid any boost creep at all.

thats fine if your treating heat issues, i was just trying to inform you. thats true it will bring on the cat up to temps sooner and improve emissions in that regard, but lets get real here, you have a skyline and your an enthusiast, are you really concerned about emmissions ?? overheating a cat does occur from a rich mixture of fuel burning inside it, which can damage it. your doing the same thing by insulating the heat inside the cat, im not saying it WILL overheat and cause damage, but it CAN, and your helping that cause with insulation in regards to performance, ive given a reply to rev210's post, so refer below a performance gain is only achieved by retaining energy/heat when you STILL want to use it. such as in the exhaust manifold, because we still have the turbine to go through and pass on the energy to it to spin it up after the exhaust is passed through the turbos turbine, it is waste, and needs to be expelled as soon as possible, with the least amount of restriction/backpressure to give the best pressure differential accross the turbine to give the most power, this is agreed on, yes ? the second point, is that velocity is NOT increased, rather it is maintained as best as possible by retaining the heat in, to say that velocity increases at this stage would mean we are adding energy in at this stage which is not true. now back to exhaust gasses being waste matter after the turbine, the goal is to get rid of this waste gas as quick as possible, by moving the most amount of mass through the exhaust as possible with the least amount of back pressure. now any given diameter of pipe ( eg 3") will flow x volume of gas with a certain amount of back pressure (eg. 300cfm with say 2psi back pressure) , by changing the density of a gas we increase its mass for the same amount of volume, thus we are moving more gasses through the same pipe with the same amount of backpressure. by allowing heat to escape through the piping into the atmosphere, we are decreasings its temperature and thus increasing its density.

i tried using that shit on my cam cover, and the results were tragic. the primer worked a charm and actually looked really good, but once the blue metalcast went on, it was SOOO flat and DULL. it looked like absolute shit it was pathetic. ontop of that, the design of the nozzle is so ingenious that the spray pattern is such that it actually clips the rim of the can when spraying, so as your spraying your creating this pool of paint on the inside of the lip on the can. my first can had a faulty nozzle and just leaked like crazy, i took it back to autobarn and they replaced it for free. tried again and it came out dull and shit again, i dont know if i didnt give it enough coats or what, i was up to 2 coats and a single can wasnt enough it seemed for a rocker cover.. after hours spent paint stripping it back to bare, i used 'engine enamel' from autobarn, no primer required, chose a gold colour, looks awesome. this is my experience

heat wrapping/coating anything after the exhaust housing should only be considered for under bonnet heat issues or other heat related issues, there is no performance gain to be had. in fact in theory, not having it wrapped and allowing more heat dissipation will allow more mass of exhaust gas to flow through the exhaust, as it is denser. although this gain is probably a minute and immeasurable amount, it tells you that there isnt anything to gain either. you shouldnt wrap or coat your cat at all, you dont want to cook your cat !

first thing i would try to find out is if: A ) this characteristic is normal for this turbo, on this engine or B ) its abnormal for this turbo/engine combo to get this sort of lag i had a lag issue on my sr20det car that had a gt2530 turbo, i was spooling early on in the range, but would take 5K rpm to hit 1bar of boost. after ALOT of fiddling around it was found that the wastegate arm didnt have enough tension on it, so when the pressure built up in the exhaust housing, it was opening the wastegate early and causing a sort of wastegate creep. unplugging the vacuum line from the wastegate didnt affect it because the pressure opening the wastegate flap was in the exhaust housing itself, not from the vacuum feeds positive pressure. so in saying all that, check that the wastegate arm has tension on it, if its an adjustable arm, give it around 1-1.5cm of tension. disconnect the vacuum line from the wastegate, and give it a run. if boost response is better, then you are in category B, same as me, which is easy fix. if not then follow the advise given on this thread, specially get your tune checked out ! after i fixed this issue on mine i started spooling earlier and hitting 1bar at 3.3k rpm WITHOUT a tune

i would hardly put bose and high fidelity into the same sentence their over priced narrow frequency range producing POS, and as far as i know they dont provide speaker specs.. and if thats how hes going about the licencing, i think hes just an absolute tool

exhaust upgrade = less back pressure = more efficiency more efficiency = better fuel economy same with freeing up the intake of restriction.

running shorter duration on the cams generally gives better low down power, maybe stepping down from 272's to 264's playing around with cam gears you should be able to shift power around on the rev range running higher compression with thinner gasket if you have a thick one, higher compression will again give better low down response maybe lightened flywheel as well, wont change the power your making, but will make the car more drivable when its off boost theres some suggestions, the first 3 will most likely lower top end though

nice show of ignorance, try to get some idea about what your talking about before trying to belittle others and calling them names defi are CHEAPER then most other JAP brand ELECTRONIC gauges, do a search and you will see HKS, Greddy, and Apexi are ALL more expensive then what you can get DEFI's for. mech ones are illegal bar boost gauge so there prices dont count. autometer are innacurate as shit, so you wouldnt bother with them at all they have peak hold, playback (aka datalogging) and peak warning with audible alert. they are a sub branch of the SEIKO company. rice ? no, just your lack of knowledge

up for sale is a front bar i havent fitted/painted or used for 180sx its the mfx front bar - tyrant version, pics and such can be seen in the below link http://www.mfx.com.au/pages/prod/180sx.htm im looking for around $300, although open to offers kavehs at netspace dot net dot au is my contact email address, and best way to contact me 0403 743 417 is mobile in sydney kaveh

hello, i have 3 used coil packs that are working perfectly (4th one is showing its age and can be had for $15 if your keen, still runs fine and you can test if you like), ive converted to splitfires so i have no use for them $60 each in sydney kavehs at netspace dot net dot au is my contact email address, and best way to contact me 0403 743 417 is mobile kaveh

genuine recaro seat for sale. no rips or burns, non smoker. good condition in sydney $530 without rail rail is not that great but can be fixed (does still fit), you can have it for $50 if you want it, fits r32 gts-t and all silvias. kavehs at netspace dot net dot au is my contact email address, and best way to contact me 0403 743 417 is mobile kaveh

ns.com has cheapest prices for these your looking at around 1K for 3 gauges and the controller to your door

the down side of a lightened flywheel is that engine revs will drop quicker when gear changing, because there is less energy to keep the momentum going what hes saying is that the tailshaft is disconnected from the engine when the clutch is in on gear change, so you dont get this affect the car itself may lose momentum quicker(although would probably be marginal), but the engine revs wouldnt be affected

ahh yes of course you are right ! while engaged in gear though the effect would be the same, but yeah the tailshaft wouldnt have the downsides of a lightened flywheel on gear change

its not a very bang for buck mod, when you can have the same effect soo much more cheaply dont you think ?

please enlighten me on where i can get a PFC for $800 thats a damn good price ! possibly a roadtune, dont have to pay for dyno hire 'hitman' i believe did this sort of tune for people

arent you just reducing rotating mass with these things ? you would get the same effect with -lighter wheels -lightened flywheel reducing rotating mass too much has drivability downsides though, car will be jerky and lose momentum very quickly - i think you would be able to cross that line (between being driveable on the street and not being driveable, or desirable) with just lowering of your flywheels mass

you would be surprised, i was reading that australias largest cane producer, in QLD has been lobbying for ethanol to be used in fuels and has also made 'donations' to howards government

just had a long think about this and this is what i came up with, it shouldnt boost 23psi, what happens on the wastegate line is basically an amount of pressure exists which is related to the duty cycle of the solenoid, the boost pressure in the plenum (or input to solenoid) and the size of the restrictor, and from experience of tuning my IEBC, it works out something like this (i didnt use restrictor in formula because it gets overcome at pretty low pressures and becomes part of the solenoids operation/purpose): boost ~= [7 (wastegate spring) ] / [.5 (duty cycle which .5 = 50%)] = 14psi so with 20psi actuator boost ~= 20 / .5 = ~40, so it takes 40psi in the plenum to reach 20psi in the wastegate line at 50% duty cycle and thus open the wastegate right ? in practice it will probably be less, because the venting of the restrictor at that sort of boost levels will be overcome too much and wont be able to vent enough to keep the wastegate line regulated to 50% of its input pressure so from that i'll need to run around ~77% duty cycle for 18psi with 14psi spring in regards to overboosting and dropping i was referring to what is documented in the book, where by say if your running 0% duty cycle all the way to load point 20, then on 21 give 30% duty cycle, it will cause it to drop boost and load point down, onto 0%, which will make it go up again, then down etc.. sort of cycles itself. then it goes on to say thats why you have to progressively build up duty cycle. my initial thought was is this going to happen with a higher spring rate actuator, because as your progressively building up duty cycle the actuator is still closed because of its higher spring rate, then suddenly pop open and cause a drop in load point - but then i realised it wont make a difference it seems, as long as you load up the actuator progressively. OK, my head well and truly hurts now, so i'll leave it at that. post up some thoughts and if ive got it all wrong let me know

thats pretty disrespectful, its akin to buying parts off some dude and taking a turd on his lawn on the way out as a thank you i just dont get why people love burnouts so much, its so boring and the biggest grab for attention

hi all, im swapping my turbo and with it comes a HKS actuator with a 14psi spring. im going to be running around 18psi. has anyone got experience with the IEBC and a higher springrate actuator ? wouldi it cause a cycling issue where it would spool, overboost, drop boost and then cycle through overboost and drop boost, especially on part throttle ? i know you get this issue if you dont progressively ramp up the duty cycle would boost controll be better/more adjustable with a 7psi actuator, or should i keep the HKS one ? im guessing you would have to load up the actuator even earlier or else all of a sudden it will pop open, lose alot of boost, then close and so on