SlikRS Posted July 9, 2008 Share Posted July 9, 2008 First post here and I come from a world of EPROM chips, TB's with standalone management and wide band lambda's and prior to that large Webbers and twin SU's... Hence I'm not entirely up to speed on how the factory install ECU on the 350Z manages to negate decreases in flow resistance introduced by less restrictive intake filters. I understand that the loss in exhaust backpressure can alter the pulse tuning of the exhaust and the resulting camshaft timing adjstments (mapped into the ECU but I don't know what the parameters are for mapping this) and valve overlaps will be thrown out (with respect to the new characteristics) altering the effects of cylinder scavenging and altering inlet reversion (which still seems to increase top end according to testimony on here and as I have seen quite often but at the expense of torque and usually IMO especially noted under load) but every other car I have worked on shows some improvement in response and often mid range/top end which validates the modification. Falling back to a simple case of swapping filter element in the airbox to a less restrictive item can anyone tell me why the resulting increase in flow and reduction in inlet vacuum (very small) under load would be cancelled out? I realise this slightly confuses the MAP sensor but in my experience not significantly when using standard induction systems and just high flow elements (though I have an air ram on another car and the load advance appears significantly affected on standard MAP at high speed up hills in high gears) though I calculated the drop in inlet vacuum to be very small as a result of the ram effect. Why would there not be more air in the cylinder and why would an ECU not read it's lambda and adjust teh mixture in teh same way as it would if you were driving at sea level as opposed to altitude or at 0 degrees celcius as opposed to 30 degrees celcius. Any assistance clearing this up would be appreciated as it's got me thinking.... Also, hi... As this is my first posting and I've only had the car 3 days having waited 4 months for the order to be fulfilled..... Quote Link to comment Share on other sites More sharing options...
M13KYF Posted July 9, 2008 Share Posted July 9, 2008 to the forum this is one which may be Prescience could answer Quote Link to comment Share on other sites More sharing options...
Zummertor Posted July 9, 2008 Share Posted July 9, 2008 Welcome, welcome ! That is quite a wait but guess you are pleased now. You are outside of my knowledge area so I can't help you I'm afraid. Quote Link to comment Share on other sites More sharing options...
Chris`I Posted July 9, 2008 Share Posted July 9, 2008 From what little I know, the filter doesnt make a difference as the throttle is drive by wire, so it only needs to open the throttle enough to get enough air in to satisfy its own demand. In a normal car, the throttle opens relative to the throttle pedal, so at WOT a less restrictive filter will let more air in. However, the Zed being a clever bugger say, oh no, I have as much air as I need so I will only open the throttle 90% rather than 100% Thats how I see it working Quote Link to comment Share on other sites More sharing options...
SlikRS Posted July 9, 2008 Author Share Posted July 9, 2008 Agh!! That would be a potential cause!! I've seen pics of the manifolds and presuming the lambda/s are placed past the primary tubes for a consistent and accurate reading are the sensors which appear to be on the primaries EGT sensors for individual cylinder trimming? Or were the photos not of a production engine setup as EGT are usually reserved for charged engines particularly sensitive to lean mixtures and melting quickly. Kinda sucks though that the engine can limit the airflow mass, and that it looks at the throttle position and the MAP sensor reading then decides what throttle position to adopt as opposed to having to adjust the fuelling to accommodate the air mass entering... So presumably as with most production setups there is a very safe tolerance in the injector duty cycle so if you did manage to overcome the throttle plate mapping the MAP sensor and lambda would be capable of compensating for simple breathing mods. I'm always interested in these things though I fear my skills in ECU re-programming are lacking... I wonder if there is a simple fault which can be induced which would result in the throttle plate resuming a linear relationship with only the throttle position sensor and not account for the MAP but without disabling the MAP so the ignition etc were maintained and you dodn't end up running on a base 'safe' MAP. I know in the world of the EPROM some of the ECU's have base MAPs depending on what fails so MAP sensor fails there is a TPS vs engine speed map to fall back on. Ah well, all beyond what I would be willing to do to the car as I've other toys to tinker with in that way. Anyone gone for a fully aftermarket management solution with something like direct to head TB's and suitable inlet tract length with home brewed throttle? Anyone tried to borrow elements of the formula renault engine? TB's etc though I guess forced induction would prove about half the price of picking similar bolt-ons (not full engine obviously) to those on that engine with far better results. http://www.renault-sport.com/en/world_s ... hnique.php Anyone have specs on one of these or know more than the 0 information provided on that site. Looking forward to getting to know the car and yet to be confident enough to disengage the traction control so I believe my power in 1st and 2nd is severely limited as she only feels marginally quicker than my wee 106 to 60mph (about 160bhp/tonne), good thing power is restored in 3rd and 4th though.... Any seriously must have performance modifications or tweeks that should be done to hone and sharpen the experience? So far I was thinking about a pair of NISMO or K&N filters and eventually if there is a improvement in flow and/or economy another exhaust but these will wait unless I can prove performance gains. Other than that I need to adjust the throttle or brake pedal (Ideally brake pedal forward a little as the driving position could be improved slightly for me but it looks like the fly by wire throttle is easier to do) to be able to heel toe her round the gears (I'm used to not having much synchromesh and it's weird not matching the revs to the gear). The only other things that will happen in time are DS2500 pads, braided hoses, possibly uprated bushes if I have issues there and possibly (probably after reading reviews though I have RE 050A's and not RE040 and I swear by RE720 on the 106 but that's cos Eagle F1 GSD3's are not produced in my wee pug 14" size) better tyres... Mine's a standard Kuro black GT, I like the clean look over the NISMO kit but may yet be tempted by the front bumper though I still think the NISMO spoiler could be improved to excentuate the car's lines and am not that keen on the side skirts. I have the sat nav but no instruction manual so if anyone has a link to a pdf or similar that would be very useful... I'm particularly keen to know if she will play DVD's as that could be a useful trick... Quote Link to comment Share on other sites More sharing options...
Ekona Posted July 9, 2008 Share Posted July 9, 2008 3 golden rules of modifying for performance... First make it STOP Then make it HANDLE Then make it GO! Quote Link to comment Share on other sites More sharing options...
Guest prescience Posted July 9, 2008 Share Posted July 9, 2008 to the forum this is one which may be Prescience could answer Yeah, thanks for that hospital pass Mike The truth is that I think I agree with most of what you are saying (jargon aside), the engine is basically nothing more than a pump and as such more air or colder air or denser air should equate to more power. However dyno experience gives the lie to this and the truth is that everyone has their pet theories but nobody really knows the definitive answer - you will only get that from Nissan. This was a hot topic a few years ago on my350Z and crops up from time to time there and you always get plenty of wild-assed theories - a lot of heat and not much light. I would suggest that if you are interested in the definitive answer, you try there. I wouldn't post up on the FI section though because what most people come to realise very quickly for this car (it look me about 6 weeks ) is that spending £1000 in the almost vain search for a lasting 10BHp NA is futile compared to spending £3000 to get a guaranteed 130BHp from a FI solution - so in fact the answer becomes almost irrelevant from a cost/benefit point of view Quote Link to comment Share on other sites More sharing options...
lotuscc Posted July 9, 2008 Share Posted July 9, 2008 An NA route would be to fit all the bhp adding mods and then get the ECU reflashed or fit a piggy back ECU and then get on the rolling road for a set up that maximises your gains. Quote Link to comment Share on other sites More sharing options...
Cool Hand Luke Posted July 9, 2008 Share Posted July 9, 2008 Hello & Welcome Quote Link to comment Share on other sites More sharing options...
SlikRS Posted July 9, 2008 Author Share Posted July 9, 2008 Thanks for the flash there Ekona, already on that band wagon though hence why my other 2 cars are running.... 106 S2 Rallye - Rear - 22mm torsion bars, 24mm ARB, GrpN cup spec tarmac dampers with new 206 XS calipers, DS 2500 pads and grooved solid discs, all poly bushed and controlled via an internally mounted screw adjust bias valve. Front - Custom made coilovers, spherical bearing top mounts, 225lb 6" free length 2.25" ID springs with 30lb 3" helpers. New hubs etc etc and after ownign a failed set of allow 4 pots she now sports 266mm 307 brake calipers and DS2500 pads on grooved and drilled (I'm not a fan of drilled but there was a mix up). ARB is 22mm, drop links and rose jointed, bushes are poly or GRpN (the rear wishbone mount) everything else is new and there is seam welding around the stress areas. Usual upgraded braided hoses and upgraded master cylinder and new servo etc etc... Engine is mildly modified, I rebuild and mildly improved the head and port matched the manifolds etc. No vernier which would have been useful as I like to run a few degrees advanced but that'll happen... My RS is a little more hardcore in most areas, best just say it's a Mk2 Escort RS Custom running fast road/grp1 tarmac rally spec with a few upgrades past this. All seam welded though with full bolt in cage and selected strengthening to the shell. The only thing I don't like about my current setup are the Gp1 front brakes (M16 calipers and vented discs) with greenstuff pads, need to ditch the pads and should really have 4 pots and alloy hubs on there. Had to make some compromises when I bult her. I won't be going forced induction until at least the warranty has run out but I suspect we'll be seeing R-35 transplants by then. Interesting to see whether this generation of engine is as well suited though being higher CR and bigger valves, neither trait being advantageous in forced induction. So with all the bolt on mods you can think of what kind of gains would be seen by a couple of hours on a dyno and a remap? Quote Link to comment Share on other sites More sharing options...
M13KYF Posted July 10, 2008 Share Posted July 10, 2008 to the forum this is one which may be Prescience could answer Yeah, thanks for that hospital pass Mike The truth is that I think I agree with most of what you are saying (jargon aside), the engine is basically nothing more than a pump and as such more air or colder air or denser air should equate to more power. However dyno experience gives the lie to this and the truth is that everyone has their pet theories but nobody really knows the definitive answer - you will only get that from Nissan. This was a hot topic a few years ago on my350Z and crops up from time to time there and you always get plenty of wild-assed theories - a lot of heat and not much light. I would suggest that if you are interested in the definitive answer, you try there. I wouldn't post up on the FI section though because what most people come to realise very quickly for this car (it look me about 6 weeks ) is that spending £1000 in the almost vain search for a lasting 10BHp NA is futile compared to spending £3000 to get a guaranteed 130BHp from a FI solution - so in fact the answer becomes almost irrelevant from a cost/benefit point of view the only tefal I could think of Quote Link to comment Share on other sites More sharing options...
SlikRS Posted July 11, 2008 Author Share Posted July 11, 2008 Awesome, have already done a lot of reading om My350z and I've found most of the technical material I need and confirmation that teh VQ35HR will bennefit from K&N panels, NISMO (for good overall gains and maintenance of stable idle) exhaust or one of a couple of other designs for slightly better performance and a re-map which will see the throttle opening 100% when the pedal hits the floor and revised ignition and fuel maps, not sure about the valve timing map though (if this is altered in the flash I've been reading about) Main gain is from flashing the ECU though even on standard setup and with the exhaust and elements seems to be capable of producing near enough or slightly over 300WHP which is a decent 10% ish gain. May even see improved fuel consumption. Overall cost is unknown though so any indication you guys can lend would be appreciated... And I'd be reluctant to send an ECU to the states for a revised MAP so would be interested in UK companies tendering the same service. This is not something I would be looking to undertake in the short term though as I've enough to be gettign on with though it is something I would like to carry out at some point in the not too distant future unless I decide to go FI but that'll likely be in a couple of years anyway. Quote Link to comment Share on other sites More sharing options...
tmJak Posted July 11, 2008 Share Posted July 11, 2008 You know way more about cars than I do Quote Link to comment Share on other sites More sharing options...
mbs Posted July 11, 2008 Share Posted July 11, 2008 Hello & wish I knew what you were talking about Quote Link to comment Share on other sites More sharing options...
Chris`I Posted July 11, 2008 Share Posted July 11, 2008 Well, panel filter will be about 50 quid, or about 90 quid for a JWT pop charger, plus £850 for the Nismo exhaust. Remap - not so sure about - ask the guys at Envy they sent theres off to Japan for a flash. Dont know of anyone who has had it done actually in the UK other than those with piggy back systems, but they cost about £1.5k to buy and have mapped. As you can see, you can get gains, but its not very much bang for buck. Hence why a lot go for FI. Quote Link to comment Share on other sites More sharing options...
IanS16 Posted July 11, 2008 Share Posted July 11, 2008 Awesome, have already done a lot of reading om My350z and I've found most of the technical material I need and confirmation that teh VQ35HR will bennefit from K&N panels, NISMO (for good overall gains and maintenance of stable idle) exhaust or one of a couple of other designs for slightly better performance and a re-map which will see the throttle opening 100% when the pedal hits the floor and revised ignition and fuel maps, not sure about the valve timing map though (if this is altered in the flash I've been reading about) Main gain is from flashing the ECU though even on standard setup and with the exhaust and elements seems to be capable of producing near enough or slightly over 300WHP which is a decent 10% ish gain. May even see improved fuel consumption. Overall cost is unknown though so any indication you guys can lend would be appreciated... And I'd be reluctant to send an ECU to the states for a revised MAP so would be interested in UK companies tendering the same service. This is not something I would be looking to undertake in the short term though as I've enough to be gettign on with though it is something I would like to carry out at some point in the not too distant future unless I decide to go FI but that'll likely be in a couple of years anyway. Speak to kingbiscuit -he went to see a guy who does ECU remapping the other day! theres a few vids on youtube too with the guy making the car do various things. Quote Link to comment Share on other sites More sharing options...
SlikRS Posted July 14, 2008 Author Share Posted July 14, 2008 Many thanks for all your replies guys it's all been a lot of help in getting to grips with what the future will hold. I'm not yet convinced I'll go full forced induction in the future as this is my main car and I'm already laughing nervously each time I have to visit the petrol station and shell out £1.20 a litre and I like the power delivery of NA..... But I do like to tweek things to get the best out of them and know how to drive a car to within an inch of it's/my abilities (though with so much at stake this is a limit I approach slowly and I'm nowhere near it yet and have yet to turn off the traction control which I believe improves throttle response etc). I like the Idea of improving throttle response and generally sharpening the package and have already carried out a small pedal modification to allow me to match the revs to the gear more accurately but as said the costs involved are not insignificant. Quote Link to comment Share on other sites More sharing options...
IanS16 Posted July 14, 2008 Share Posted July 14, 2008 Many thanks for all your replies guys it's all been a lot of help in getting to grips with what the future will hold. I'm not yet convinced I'll go full forced induction in the future as this is my main car and I'm already laughing nervously each time I have to visit the petrol station and shell out £1.20 a litre and I like the power delivery of NA..... But I do like to tweek things to get the best out of them and know how to drive a car to within an inch of it's/my abilities (though with so much at stake this is a limit I approach slowly and I'm nowhere near it yet and have yet to turn off the traction control which I believe improves throttle response etc). I like the Idea of improving throttle response and generally sharpening the package and have already carried out a small pedal modification to allow me to match the revs to the gear more accurately but as said the costs involved are not insignificant. What pedal mod was that? sounds pretty cool! Quote Link to comment Share on other sites More sharing options...
Chris`I Posted July 14, 2008 Share Posted July 14, 2008 Many thanks for all your replies guys it's all been a lot of help in getting to grips with what the future will hold. I'm not yet convinced I'll go full forced induction in the future as this is my main car and I'm already laughing nervously each time I have to visit the petrol station and shell out £1.20 a litre and I like the power delivery of NA..... But I do like to tweek things to get the best out of them and know how to drive a car to within an inch of it's/my abilities (though with so much at stake this is a limit I approach slowly and I'm nowhere near it yet and have yet to turn off the traction control which I believe improves throttle response etc). I like the Idea of improving throttle response and generally sharpening the package and have already carried out a small pedal modification to allow me to match the revs to the gear more accurately but as said the costs involved are not insignificant. What pedal mod was that? sounds pretty cool! +1 - we want details! Quote Link to comment Share on other sites More sharing options...
SlikRS Posted July 14, 2008 Author Share Posted July 14, 2008 It's nothing cool, I just stripped the pedal down, mounted it in a vice, warmed it and bent it gently. I may yet tweek the position but it still stops on the backing plastic block and not the sensor so shouldn't be puting undue stress on the sensor. I brought the pad out a little which was better but needed it left too in order to be fully confident on the brake while being able to dab the accelerator. The result at the moment is that the pedal is sitting at 20 degrees to the vertical as I didn't have the tooling to put an S bend into the pedal over as short a distance as was required. It's a mid term fix to something that was really pissing me off and matching the revs allows far easier and smoother shifts and sounds good too... If I get the chance I'll get another pedal mechanism and have an engineer bend it accurately. Quote Link to comment Share on other sites More sharing options...
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