**RB2530**

Has anyone ever tried using a non contact temperature gun (too early in the morning for me to remember the exact name) to measure individual cyclinder EGTs...should be easy with a high mount manifold...Just point at each runner....

This is true but only in a static sense...As soon as flow occurs you have friction on the walls of the plenum as well as turbulence and the pressure distribution will be different...

I try....I am having an interesting day....

But our high powered cars are also lower and therefore if we hit something it is more likely to roll over the top of the car and therefore impact is lower...We also have wider tyres so the when we run someone over the weight is more evenly distributed and less painfull...I also have a big fat BOV and often if a pedestrian runs out in front of me I back off..... pphhhtttssshhhhhh!! and the pedestrian is blown out of the way before I hit them.... Nah I think donating blood is an awesome idea and a good cause and I'll be in if I can make it....

Where are you at? I have found most city centres have at least one good bolt and engineering supplies shop...In Newcastle it is called Newcastle High Tensile...funny enough.. Anything for exhaust work such as studs, I go to places like GCG. +1 for goods brands such as ARP..Yes they sell expensive bolts but its more about getting what you paid for...I have been to XXX (name omitted by author due to libel risk) automotive stores before and bought their high tensile bolts only to have them strip or break which is a pain in the arse and wastes a shitload of time.. Also I have never seen any decent automotive bolts in hardware stores either..

Check all of you vacuum lines...The BOV might not getting enough vacuum to open and thats why you are getting mass flutter....

I am not a legal expert but this is my take on the situation... Defemation is when an individual or organisation experiences loss of income or reputation (really these two are related) due to groundless negative comments made by another individual or organisation in the public domain... Where i) Loss of income (damages) can be demonstrated. For the organisation concerned this would be a reduction in clientele and easy to demonstrate. This could included failure to meet business growth targets. (putting down the prime minister would not reduce his income so not much of a defamation case) ii) The comments made were unfounded and of no basis. ie someone claimed they were ripped off when in fact they weren't iii) SAU would be classed as public domain. No question about that. SAU is even worse because it is has very close relationship with potential clients of the businesses in question. So if the organisations in question got wind of these negative comments within the forum, points i) and iii) are just about a given. Point ii) is where it gets tricky..because It is always the case that these issues are complicated...If SAU were in a position to verify everybodys bad dealings with suppliers then they could allow slanderous (I think technically it is only slanderous if it is untrue) comment on the forums as long as there was proof behind the comments...BUT the reality is that this would cost a lot of money to do and 'I' certainly dont expect this to happen... So although there are many shit suppliers out there and I hate seeing people getting ripped off, I also dont want to see SAU suffer undue expense in having to go to court and potentially being shut down... Like it has already been said...Use PMs for this type of communication...By definition it is not in the public domain and therefore defamation is not an issue..

Yep I agree...Thats true for any type of pump, transferring any type of fluid...It just so happens that with air it is very easy to heat...thank god for modern turbine design...more energy into moving air, less energy into heating it...

True...but even of airflow is 1/10th the extra time taken then becomes 0.16s.... Something I didn't mention earlier was pressure drop...For the same airflow, the bigger I/C would in theory have smaller pressure drop from inlet to outlet. So that would in turn reduce lag...It may be that the lower pressure drop counteracts the extra time fill the I/C As far as throttle lag is concerned, wouldn't it be the same irespective of the I/C...The same as lag from the rest of the intake pipework...

PS If you also run large intake pipework the effect of a larger I/C would be less noticable (lag wise) because the overall change in intake volume would be smaller...

Now I have done some calcs...Yes I am bored at work...I have resigned and starting a new job in 2 weeks... I have done some numbers on the time difference between filling two intercoolers... I have compared a 600x300x76 with a 600x300x120...I have also taken some rough numbers from a GT35 corrected airflow chart and made a couple of other assumtions that I will explain.... Volume of I/C number 1 = 0.01368 cu m which = 0.4831 cu feet Volume of I/C number 2 = 0.0216 cu m which = 0.7627 cu feet Now this is the total envelope of the I/C...I made the assumption that the internal volume of the I/C was about 50% of this including the tanks... So the difference internal volume between the two is = 0.1398 cu feet Corrected airflow for a GT35 gets up to about 40 lbs / minute Assuming an air density of 0.076lbs / cu feet this equates to 526cfm or 8.77 cfs... So time taken to fill the extra 0.1398 cu feet at 8.77 cfs is equal to 0.016 seconds... Now this is only a ball park calc but hopefully it makes sense and puts some scope around the lag issue with bigger I/Cs. I dont think lag becomes an issue.

+1 from me... Heat soak is another issue...Larger coolers have a larger thermal mass due to more aluminium so they will run cooler...

I can't see how a bigger I/C can introduce noticable lag...Yes there is more volume in the I/C but if you look at the flow rate of air going into the engine veresus the increase in I/C volume (might work this out...give me 4 hours) I wouls say the time taken to fill the extra volume in the I/C would be very small.... The test for whether or not the I/C is big enough is what temperature is it cooling the inlet air to...Basically the cooler the air, the better...But at best, an air to air I/C cannot cool the inlet below ambient temperature....So if you check you inlet air temp on a 25deg day and it is actually 25 deg, the existing I/C is big enough...If it is measuring 50 deg, there is room for improvement...At the moment my cars intake setup (600x300x76) at 60% load has only a 4-5 deg temp increase from ambient temp to throttlebody... This is a funtion of the I/C but also the entire intake setup...I could go a thicker core and get that down to a 2-3 deg temp increase, gain more power, but probably not much more and the cost of gettign a bigger core in there would be high...Cost vs benefit not high enough.. And just one extra point..I hear it many times that car-x makes y-kWs with standard set up already so there is 'no point in doing mods'...This is a risky statement and often just not true....In reailty you can't make that statement without first either, doing the mods and measuring no benefit OR understanding the science and taking real life measurements then drawing the conclusion that it is not worth it... Not having a go at anyone, just bored at work and filling in time...

I used a throttle cable from a Nissan Pintara....I just went to the motor wreckers with the R33 one and had a look at different Nissan cars...I matched up the accel pedal end...The end on the throttle body is clamped with a nut and bolt...The bolt has a hole drilled though it just under the head and goes through the pulley on the TB..the nut is tightened down onto the cable... One thing with the throttle cable is make sure that the inner cable and out cable at the throttle body are on the same axis..ie make sure that the inner cable pulls out squarely. If is doesn't you will make your pedal heavy and wear out the cable quickly...Too me this seems obvious but I have seen many custom throttle linkages that are failures waiting to happen...

The stock airbox is not sealed from heat...You have heat transfer from the engine bay into it...It is made of plastic and heats up...The heat transfers throught the plastic towards the inside...The inside wall heats up and there you have it...Heat into the inlet air... As far as the RAM effect is concerned, the factory snorkel is pretty piss poor...The end of it does not see the road speed stream anyway because the bonnet is in the way. It is design just 'pull' cold air from just above the headlight... Btw I worked it out once that any ram effect at 100km/hr will give you about 0.25 psi pressure increase and thats all...It is not much...And as soon as you try and draw more through it than what is flowing into it naturally due to road speed itself, you end up with vacuum inside anyway... A good airbox design is: 1. Insulated from the engine bay as much as possible. 2. Has an inlet or inlets that are large enough to introduce more cool road speed air into the airbox than the engine is likely to need. 3. Is not completely sealed so that excess road speed air can flow out of the airbox...(if this doesn't occur flow into the airbox will also be limited and it will start to heat up...

Check that you haven't caused any exhaust leaks during your decating process (did you replace gaskets) Do this by letting the system cool down completely and rub 50/50 dishwashing liquid and water over the flanges. Then start the car and look for bubbles...

Dyno testing will rarely show improvements gained from CAI and air box mods. This is true and the reason being is you dont have decent air flow at the front of the car apart from the cooling fan that is commonly aimed at the radiator..Obviously when you are out driving there is a fully developed laminar flow hitting the front of your at a speed approximately the same as your road speed...This is a very different scenario to the Dyno set up...So I agree that the dyno may not show any improvement, but thats not to say they dont exist.. The way to test for intake mod benefits is: 1. Place thermocouple in your airbox or in filter element and another thermocouple where the air comes into the carfront bar to pick up ambient temp at the front of the car..Your design is well designed if you get no or just a very small increase in temp between these two point...You can also do this between the airfilter and the throttle body to check for IC and IC pipwork efficiency

Most nissan afms will have output of 0-6ish volts. They do this as the ECU will register up to 5.12V exactly ...this is the limit of the A-D converter in the ECU..To detect 'maxing out' you really need to log the afm voltage vs time or if you measure an afm voltage of 5.12v you are on the limit..

As far as getting a profile is concerned a trick which I use sometimes is this... Get some aluminium foil and scrunch it up very loosely and place it around the edge of the airbox. Then close the bonnet... open up the bonnet and hey presto, in the foil you should a fairly accurate profile of where the the inside of the bonnet comes to imbedded in the foil...There are many things apart from foil that you can use but I find foil works best...It squashes with a minimum of force and will not recover after the force is removed..It may take a few goes to get it perfect but it has worked well for me every time.. As far as using the clips...wont the bonnet hold down the aluminium frame anyway?? As far as fire retardant foam is concerned I dont see a need for this...I would use some thermal insulating to prevent engine bay heat from transferring into the air stream... If you really want to get efficient, line the base of the air box (probably the outside) with thermal insulation foam...You can even wrap the intake pipework with the foam..All this prevents heat soak from the engine bay ... Good luck

The BOV also provides internet forums with hours and hours colourful discussion and debate... Now here is my 2c... In theory it also reduces the loss in turbine rpm during a gear change..This means when you get back on it, the turbine is at a higher rpm (because the compressor discharge hasn't been suddenly blocked) and therefore will spool up quicker...In practice though this may not be noticable much, if at all. It is also very hard to measure...

Gotta luv these BOV discussions...

Rich and retard is from what I have experienced, only subtle. The car just feels flat... The CAS position for stock base timing (15btdc) varies from engine to engine...That is why it is adjustable...For stock engine with new cam belt and no adjustable cam pulley etc 15 deg btdc would be close to the middle of the adjustment slot.. You need to become familiar with what pinging sounds like...If you know what it sounds like you can advance until pinging occurs and then retard it 2-3 deg to be safe...If you dont know what pinging sounds like (it harder to hear with loud exhaust) get it set by a workshop...You can do it yourself with timing light...there are many threads on how to do this...

As I said ignition advance is a compromise...If you want to trade off safety run more of it and get more power...but you are closer to detonation or pinging as some say...With stock ECU detonation is your enemy as well because if the knock sensors pick up detonation it goes into rich and retard mode...so you dont win... At low power levels detonation will f**k the engine over time...It damaged piston crowns and combustion chamber surfaces...it also roots your spark plugs...other not so visible signs are shortening life of gudgeons pins and conrods etc etc At high power levels detonation can f**k up your engine in an instant!!! Bang... broken piston, gudgeon pin, conrod and holes in the block as well as bent valves...

Your question cannot be answered in a direct sense..ie how much power am I playing with...There is an optimal ignition advance and it is based on so many things...some of theses things are fuel RON, compression ratio, afr, inlet charge temp and combustion chamber design... If you retard ignition timing you do not yield as much energy from the fuel...if you advance the timing too much you yield all of the energy from the fuel but because the peak occurs prior to TDC and some or most of that energy is wasted in trying to force the piston down too early. If you do this you are trying to rotate the engine backwards...In reality this doesn't happen due to inertia of the engine but you still do mechanical damage in the process.. Bottom line is if you are running a stock setup, run stock base timing...It is an optimised compromise of power, economy and safety...

Kev, I left this post but didn't send an email si I am probably not on the list...It turns out that I can't make it now anyway...I am not an SAU club member anyway..(soon to be though...just waiting for reply and money to go through) Will be very keen for the next one though.... cheers