Kustom20

It almost sounds like air leak - but if the vehicle run better than ever then its obviously not having boost leak issues - and when the vehicle is revved a bit it balances out with fuel compensating for the smoother AFR level - but at idle decel closed throttle steering and brake it has trouble. I would have also said IAC/AAC maybe sticking as it controls the air flow for idle at closed throttle - but if you have checked this and cleaned it out that should eliminate it being the issue. For it to be sporadic idle at cold start or low revs and decel tends to lead towards AFR issue - brake would add air through booster and steering adds idle through power steering sensor. So with this if their is already excess air being added to the inlet and when you push the brake pedal - a bad booster will cause idle issues but it would be constant bad idle and you would no doubt hear the hissing sound. Has the vehicle been re-tuned after the Z32 was installed? On the MAF have you got the Ground to Chassis and Ground to Signal Ground - its probably had this running perfect for ages but just checking - as I have had a few tuners mention about connecting incorrect ground and works for a bit but can cause issue eventually. And some users of power fc sticking to the base AFM setting 3 for the Z32 and it needs to have a better air flow curve based on different vehicle mods. How long ago did you replace the fuel filter? - I know some have removed their fuel filter and couldnt even blow through them Has the vehicle ever had a fuel issue? and has the fuel pump been replaced or upgraded? Again its hard to believe this could be an issue as its only at cold start and not always Do you have an after market ECU - if you could log the idle to see the numbers that would be great - we could take a look at your air flow vs other to see the values. Maybe your AAC valve is sporadically on its way out

Today I pulled the engine down and found that a brand new camshaft seal has issues, the inner surface or sealing face had actually pushed outwards in one section. Definitely wasn't like it after the first assembly Obviously causing a pretty good oil leak down the front passenger side of the engine. Im not concerned on this but more why it has occurred after first assembly during tuning. I have removed the PCV and installed Catch Can - crankcase pressure should easily vent through the rocker covers and intake pipe with no issues I would presume - I would find it hard to believe that with no resistance on the rocker cover ventilation that it could blow a cam seal. New Seal fitted Engine is all back and ready now just waiting for some curing and tomorrow will run the engine bleed coolant system and check for any leaks

Has the engine had new oil put in? If so what brand and weight? Maybe check your oil pressure and turbo seals, is it constant smoke if the plugs are fouling up would be a sign of combustion chamber oil you could eliminate the source of the oil burning up by possibly checking plugs. 140K shouldnt be too bad on the rings though depending on how hard the vehicle has been driven. If it is rear turbo seal then it wouldnt be combustion chamber and you should see signs of oil leak on the rear of the turbo. Oil pressure to the turbo cant exceed otherwise it can pass the seal. Have you done anything to the engine or did it just start to slowly get more smoke? Or did it just start smoking bad all of a sudden? Has the vehicle overheated could even be a head gasket between the oil journals or returns. If this was the case you would be seeing more blow by as the number 3 appears to be 10 to 12 below the highest reading. Could even be valve stem seals or depending on the smoke color if it is white then it seems more like moisture/water blueish is oil being burnt. Maybe post up some more findings and can help narrow it down. Is it constant cold start or when it gets more to operating temp? Hope this helps

Also a Picture of the Z32 MAF (AFM) on the coolside below inner guard after Intercooler Outlet - in vertical orientation

I have now completed modifications on the TOG manifold and have the vehicle back together - I would like to note the following that I have noticed after the new modifications - boost has now stabilized right through the rev range at the low setting 15psi and now doesnt have boost creep. See below images for mods on the manifold TOG Manifold ready for the old wastegate pipe to be removed New piping for the Turbosmart Hypergate 45 - I chose 2" or 50.80mm ID Schedule 10 304 3mm Wall - as you can see larger diameter to release exhaust gas over the total flow of the 6 cylinders into one collector compared to the original 36mm tubing In these 3 images it shows the standard hole size after the piping was cut off and how the original pipe was offset to basically one tube on the collector. You can see even how restrictive this would be as it would try to release exhaust gas over 6 cylinders and try to exit out this small diameter - obviously lower boost and revs were able to stabilize it - but at higher RPM and Boost the exhaust gas would try to find the path of less resistance and being forced more out through the turbine and 3" Dump - Hence Unstabilized boost This image - I have taken a measurement of the inner guard (Shocker Tower) and simply clamped a rule into place to ensure that when I manufacture the new piece I know there will be shocker tower clearance - also have the turbo bolted up to ensure there will be no clearance issues. Alternatively I could do it all inside the engine bay as Tig Welding we have no spatter - as its only a wastegate tube and small size not too extensive but easier to have plenty of work space in the manufacturing area and have a simple dimension for clearance. Tack up quick refit before final weld New hole has been cut with a holesaw in the drill press - I also had to weld a small piece over the original hole because the pilot hole needed was right where the other tube was cut out - this allowed the holesaw to be used - I didnt want to plasma cut this - also less cleanup after holesaw New section machined with correct angles to get a nice tight fit for welding - this took a little amount of work to get correct angles needed, With the original Turbosmart V Band for the 45mm Gate - I needed to machine the inner surface for the larger diameter tubing - it was machined on an angle - in the image you can see the standard V Band Flange angle and the flat section across the top facier - this is standard and I machined it all the way to the outside edge to ensure smooth flow after welded onto the new tubing. Basically the outside diameter of the V Band on the top face is 1mm difference to the Inside Diameter of the Sched 10 pipe New pipe fitment before welding Completed manifold ready for fitting - wastgate tubing slightly angled upwards then down - you can see it curves up then down towards wastegate end - this allows a smoother flow rather than straight out at 90 and 90 degrees I also wanted to post this as the original post the image wasnt really that clear - power steering bottle bracket relocation - used original bracket as mentioned - cut one side off folded flat and put another bend in - took about 5 minutes - for those who are looking to relocate bottle from the standard position - I also used a 12mm and 19mm hose joiner and some hose to suit to extend. Also need to change the current boost gauge as it is only a baby Autometer Pro Ultra 20psi to a min 30 - should get this done in next day or so Next job fix new oil leaks coming from what appears to be the new Camshaft Seals After these jobs are completed - Cant wait until week 11th January when it has its final tuning and power run on the Dyno.

Ha thats funny man - Christmas is only another day on the Calender sounds like your preaching to me. lol The only thing I did was covered everything for this stage of upgrades, fuel and air. as far as being bullet proof again that all comes down to how you drive them and what tune is in the car. We see many people saying they have big amounts of power but it also comes down to what your going for, track car, dyno queen, burnout pig, drift king, drag car, show pony. they all have there own uniqueness and characteristics - there are guys in the big smoke running 7 second daily drivers. But as far as this stage of mods goes yeah its coming together and looking forward to its next tuning day

Yeah should be good Nick - gotta get some argon tomorrow for the tig and some sched 10 steam pipe bends - then pull it all apart to cut and weld the wastegate tube - pm if ya want to catch up before xmas will be home or at workshop most days.

Hi Guys, so finally completed my build and had first day of tuning friday 18th with Chequered Tuning - http://www.chequeredtuning.com Firstly if anyone would like any images of mod's on the below article I would be more than happy to send more detailed ones through. For those of you who dont know Trent and Catherine from Chequered Tuning - check their website and some may know Catherine as Driftcat and Trent is an excellent tuner and extremely knowledgeable as one could imagine. Trent helped with certain aspects of choosing right items for the application and steering away from others - the only thing I forgot to mention was the Z32 AFM that I purchased tried to get the good old cheap cut corner type of ebay crap copy to save $180 or so and yep thats what happens on your day of tuning - throw it in the bin and - I have just driven over 250kms with the car on a trailer to find out that they are pretty much useless, then Trent and Cat say they have a friend just around the corner with a business and he would have one, so we walked just up to the cafe in the same building block as it was about 40+ degree's on Friday kicked back and had a bevo - and Trent and Cat arrive back within ten minutes - brand new genuine Nissan - and we are now good to go. Trent did try the ebay crap one first but he did advise these are useless and they shouldn’t even be able to sell them on Ebay or anywhere, And I also want to mention that his time on the Dyno is amazing - no time for talking haha - he works very efficient and still has great conversation while working. 3 Weeks ago Day before Tuning Large FMIC - 3" intercooler piping GTX3582R Dual Bearing AR.82 – 11 Blade Billet Comp Wheel TOG Steam Pipe Manifold – Tuned Length – 45mm External Turbosmart Hypergate 45mm Wastegate 650CC Smartfire Injectors – Top feed Upgrade 345LPH in tank Topspeed Pro 1 fuel pump Adjustable FPR Z32 AFM 4 Inch Air Intake Custom Plenum 80mm T/B High Flow Air Filter 3 Inch Dump Pipe High Flow 3” Cat Twin Kakimoto Exhaust – Cat Back Turbosmart Dual Stage Boost Controller Greddy FV BOV Plugs – Gapped 0.8mm - for initial first tune Oil Catch can – Plumbed to Intake Pipe – PCV hose plugged Alloy Radiator – Twin Thermo’s Wideband O2 Gauge AFR – Bosch Lambda LSU 4.9 Boost Gauge Apexi Power FC Cometic Head Gasket H/T Head Studs Cometic Intake Manifold Gasket Timing Belt Kit – Gates Racing – Idler and Tensioner Bearings Alt/P/S Belt Oil Pump 77c Thermostat Fuel Filter Thermostatic Controller After day 1 in tuning some issues found - see below TOG Schedule 10 S/P Manifold - Issues Found with the GTX3582R and Turbosmart Hypergate 45mm - Noted Below Issues: 1. The wastegate is too far away from the collector and we want to have least path of resistance for stabilizing boost control 2. The piping size they use as you can see on the V Band Flange where I have marked in green has about 3mm or 4mm from the edge which means the pipe size is incorrect for the Turbosmart Hypergate 45mm - the pipe size used is OD 42.2MM & ID - 36.6MM and should be 45mm ID or I think it is 44.45mm that is available. - This is in their description 45MM WASTEGATE V-BAND FLANGE ( YOU CAN EITHER CUT AND WELD YOUR TYPE WASTEGATE ON OR YOU CAN USE TURBOSMART HYPER GATE 45MM FLANGE WASTEGATE) 3. Red - cut this pipe off completely 4. Blue Circle notch out an oval shape where we can form a nice 2 pipe to one flow at 90 degree - providing us with smoother exit of the exhaust gas to help stabilize boost 5. Yellow line is where the new 45mm V Band will be welded with correct merging of pipes into one at correct diameter 6. This will sit the wastegate closer to Turbo and having a better path for exhaust exit - and with this manifold the dump pipe and the Hypergate 45mm it will still fit nicely and either screamer out or can easily be made to enter smoothly at reduced angles to the dump pipe 7. When the manifold is completed I will post a picture 8. With this current setup on the TOG with GTX3582R and Hypergate 45mm - Boost came on pretty nicely set to 15psi for the base run and at a certain rev range - boost just wanted to get to 30psi as fast as it could - It climbed peaked stabilized at the set 15psi then after a certain rev range boost creep came on strong 9. In the next stage of tuning I will also add the outcome of stabilizing the boost levels - sometime around January 11th 10. Another issue that I had with this manifold is on the RB25det - R33 Series 2 - the number 3 cylinder exhaust outlet hits on the engine mount bracket that bolts to the engine - the black coated one - I simply marked out a curve where it was hitting and grinded/cut that edge out and plated just below to add strength - the part that was cut out is the structural bent edge on the top right hand side looking at the engine from the passenger side wheel - roughly 5mm needed to be taken out. 11. Other than that the manifolds are great quality just a few minor adjustments needed 12. Great Rocker cover clearance as we all know many manifolds dont have this because they are designed for smaller turbochargers - great shocker tower clearance as well just needed to adjust Turb housings During the mapping/tuning and the boost creep wastegate issue - Trent also went up to Havoc Fabrication which is also in the same complex and had the fabricator come down to check the manifold - he took us to his workshop and showed us some very interesting items he is working on - the quality of these guys work is top class - he showed us some twin turb and twin wastegate setups and how they merge the pipes and have it close to the collector for maximum release. If you want custom turbo manifold work carried out check these guys out. He commented on the TOG and said its a really nice design just the wastegate outlet thats all. POWER STEERING BOTTLE: this was as simple as removing the bottle cutting the bracket on the right hand side - flattening the bracket out in the vice on one edge and folding a new edge - then bolted back to one of the original holes and drilling a new one and nyloc nut in the wheel arch - bringing the bottle around from the current position - in this picture the Comp housing looks close butfrom standing at the passenger wheel there is clearance - intake pipe was also purchased from the same company as the TOG manifold allows and has vacuum tubes welded in already, just needed to plug one off with a 12mm rubber plug Oil catch and plugs for piping ends with the 19mm rubber plugs the local shops here were limited so the person I sent to get the plug went to mitre 10 and came back with a rubber chair foot - worked that good did not even need clamp - very tight MANIFOLD, INJECTORS, INJECTOR RAIL - this went together like clockwork cut a few pipes re-routed hoses, I also purchased a windscreen washer bottle from Burson's I just gave them a dimension of 100x100xH200mm - they had almost the perfect size complete with hoses switch pipe fittings cables (I didnt need all that but anyway)- the Factory R33 washer bottle motor fit into the new bottle I simply removed the new and put in the R33 - then I drill another 20mm hole and fit the secondary motor from the R33 and now I have the perfect replacement bottle both motors and excellent clearance for the new Manifold T/B and Intercooler Piping. Another modification I needed to do on the Intercooler piping just before the T/B was a 19mm tube for the IAC valve intake tube THROTTLE BODY - 80mm T/B issue with the unit sticking open slightly at low revs sometimes 3000rpm - when you back off throttle holds open then a quick touch it closes - Trent loosened nut on side to see if it was excess tension - even placed a second return spring and it is still doing it - so Trent was able to tune to a certain point based on the previous boost creep it was limited for the tuning - I have pulled apart the T/B and checked now and found that the 2 bearings on each side of the shaft were pressed way too tight, when I had everything apart and only the 2 bearings and shaft in the T/B it was tight to some degree, where as a normal T/B should free spin easily. I pressed the shaft out and voila bearings free spin - reassembled with 0.5mm clearance and the bearings and shaft work great - installed back into the vehicle and test drove while data logging and the sticking throttle has now gone. Z32 AFM - Make sure not to buy copy item on this - purchase the genuine Nissan AFM - This has been setup boost through on cold side mounted vertical below inner guard where the inter cooler piping comes out of Throttle Body (If you would like picture just message) - AFM Harness extended with 5c Trailer Cable and wire ran along the underside of the radiator support panel - reversion don't even notice it - and wiring for the Z32 AFM for R33 - Make sure you dont splice or join the 2 ground wires together for series 2 - 3 wire AFM to Z32 - the Z32 needs to have the signal ground to signal ground and the chassis earth as mentioned it is chassis earth for a reason. BOV - Vented to Atmo and it is directly opposite the AFM but on the passenger side below inner guard mounted vertical - Vac Line from Manifold Behind T/B and ran along the drivers side and along the underside of the Radiator Support Panel SILICONE INTER COOLER HOSES - popped a few off on the initial load testing once they were tight - boost away - I will explain below on this SMFI INJECTORS - So far so good the Smartfire Injectors are performing very well - we have 650's in for now testing the performance of the SMFI type - and if needed we have 1000cc and 1200cc FUEL RAIL - after I completed the installation of the fuel pump and were ready for its initial priming to test for leaks and pressure testing at different levels, when I first added pressure/flow 15psi - I had 2 fuel leaks - and this point was late in the early hours of the morning - yep fix it tomorrow, the next day I found the issue I had double O-Ringed all injectors and somehow had missed one injector with the double o-ring and yep the O-Ring that was on this one particular must not have had enough slippy stuff and one edge was flattened - when I replaced and doubled it perfect, so good lesson double check your double o-rings and ensure to add sufficient KY VAS LUBE OIL whichever you choose, The second leak was in the AN 90degree fitting at the rear of the fuel rail - Maybe I over tightened - but this particular fitting I noticed when tightening it was moving around like it was slightly bent hence why it wasnt sealing - misaligned contact surface - changed it out and sealed great. I then performed testing at 5 minutes intervals with 30psi - then the stock 43.5psi all seemed well no leaks - I continued to increase fuel pressure to 63.5psi and all the way to 80psi with no leaks in the system while running cold test. I was curious to see when heat transfer was applied in tuning. All went well FUEL PUMP - Topspeed Pro1 345LPH In tank Very easy conversion - unscrew everything take it out remove old pump fit new pump put back in - the only issue was the big black plastic nut holding the pump assembly into the tank, blow dust away with air, spray with WD40 so the threads get penetrated with lubricant, use a 3foot long piece of steel tube and a big whacker, slowly hit each tooth on the big black nut anti clockwise, it moves about 2 inches at a time until it is ready to unscrew by hand. Another note people say the black o ring needs to be replaced when removed because of expansion but just take your time be careful dont stretch anything and it will go back in with no issues and you wont be able to smell fuel in your boot, thats why we use WD40 so the Black Nut doesnt bind on the big o-ring causing stress and stretching it. When the fuel pump is out you can either inspect the sock and use it - or use the new one - or purchase stock sock - there are many discussions about this but I used the new sock - the pump doesnt suck fuel from the lowest part of the sock - it is like a sludge pump so to speak it will lie across the bottom of the tank and if only if the end or half the sock was full of sludge which if you have this clean out your tank - impossible - but like in a dam with water and mud they will block 3/4 of the sock and still be able to suck through, some people see the long sock and think that the new pump with a short sock will only suck 3/4 of a tank of fuel and run out now with a shorter sock - not gonna happen unless you mount the pump 1/4 of the way up that steel bracket. Hope this helps most socks will fit the walbro and other universal in tank pumps - be sure to use the rubber surround and cable tie the pump - I also used the rubber base plate and cable tied it into place as well. Another one in discussions is that some people ask about the wiring in the tank and worrying about sparks and earth in fuel - dont stress their is no metal or earth other than the earth wire - use the standard terminals they give you with insulation - you wont get spark jump from the terminals unless you have serious amps like tig welding or coil packs and dodgy wiring - the wire is submerged in fuel so no spark jump - I used solder and heatshrink and small cable ties to clean wire to bracket and the tank is not earthed or made of steel. Intercooler Piping This was a matter of choosing the right bends and pipe size for the application - I found a company AUCXRACING where you can choose 6 bends of any degree and size, 6 silicone hose joins of any type and 12 T Bolt Clamps all for $119.00 - I chose 3" all the way as it was easier and less reduction from turbo to throttle body, just took maybe 20 minutes after everything was ready and in place for the piping to work out bends and silicone joins - with this front facing manifold and R33 with the Top Mount GTX3582 - 80mmID T/B was 3 1/2" to 3" Straight Reducer 70Degree from T/B downwards then AFM into 90degree - 90degree into intercooler - from the turbo to intercooler is 2 1/2" to 3" 90degree Silicone Bend Reducer to 90degree into straight silicone 3" into straight 3" BOV Adaptor with straight silicone on each end then 90 and 90 into intercooler. Bottom line was 1 x 70degree 3" Alloy Bend and 5 x 90Degree Bends Oil Return Line from turbo This was custom manufactured to suit the GTX3582R in the position I have it - I wanted as much steel tube from the turbo to the return inlet on the stock pipe - here is what I had done - on the stock turbo it has a 45deg oil return tube on the turbo end - I cut the standard mounting bracket/flange off and now I have a perfect 45deg bend for this setup - I traced the new GTX3582 oil return flange size onto some mild steel plate and cut and drilled out - took about 5 minutes - then for the rest of the steel tubing on the standard R33 RB25det as below in image marked in red - cut this off and used for the rest - I welded the 2 pipes together - the joins length and angle was dead inline with the oil return on the engine - Now I dont need to stress on rubber tubing too close to turbo - it has about 150mm section of rubber right down the bottom. Or you can buy this type - In the kit I purchased it was manufactured for GTX3582R for RB25det but only had the Oil Feed, Water Feed and Water Return all in braided - but missed the kit with the oil return - so just used some brains and manufactured - good to have all the tools Turbo Smart Wastegate - Hypergate 45mm Anyone needing to setup with manual dual stage see below - switch in car on accessory power There are many other small mods done while putting the new upgrades on like dump pipe using stock 3" and adding only a couple of extra insert pieces with the 4bolt flange, AFR wideband install, screamer, water hoses under the plenum, injector loom extension and fitting the EV1 plugs, the PCV valve has a dummy tube plugged doesn't actually do anything all vents through catch to inlet, removed all AC unit components, Injector loom on the underside of the plenum - I found it easier to run the injector loom down between the runners as in image feed the back three then the front three - trying to run the whole loom from the front or under the side down near the fuel filter side is impossible with all the piping and IAC and other - also front is very restrictive with the water neck - you will need to extend the injector plugs with wiring to have the loom on the underside of the plenum Removed factory boost solenoid located near power steering bottle and sensor - ECU does not require these at all they are only for factory boost setting for the stock turbo and the sensor on the drivers side just near the brake booster is only for the factory boost gauge. Hopefully I caught some things in here for anyone upgrading or using certain parts in their builds. I will also put up the Dyno runs when I have them all together - there are a few numbers but with the sticking throttle at tuning along with the wastegate boost creep obviously we know it is no way safe to run the full testing - at moment has 225kw with 351nm and the second reading was 298kw with 450nm - boost was coming on at about 2500rpm - from 4000 to 5500rpm was 15psi and held through to 5500 rpm then from 5500 to the 6500rpm was 24psi - and in the time it takes to see this and take off throttle is very quick I think with the next tuning day the low boost will hit the same mark and stabilize right through the full rev range The second boost or high boost setting should hit the full mark between 4500 to 5000rpm as the linear curve in theory from looking at my sheet will continue along this curve line. Around January 11th to 12th should be the next tuning day and will upload results

Hi Johnny, thanks for your advice on this we have the other available sizes here on the shelf. No doubt I will be sending you a message advising we have used the 850's or 1000's - maybe we can list the top feed 650's for someone upgrading an SR20 or RB20

Josh, I think some people like to be on the higher side, nothing against those wanting to say I have 1000cc injectors or 1600cc injectors. It comes down to basic formula and knowing what target hp or kw one is intending on getting out of there application. And the extra percentage headroom is always great - we dont want to stay borderline Thats right with injector sizing and duty cycle - for 6 cylinder 450hp @ flywheel only need 492.2cc injectors running @ 80% duty cycle the calculations are endless based on sizing type of engine hp duty cycle and so on, and then bring this all together with mapping and tuning We have chosen the 650cc for our initial sizing and have 3 higher variances to choose, that being 850cc 1000cc and 1200cc 650cc are good for about 595hp @ flywheel for 6 cylinder running @ 80% duty cycle 43.5psi - 62 lb/hr - 0.5 B.S.F.C Should be fine come the day of tuning and mapping as we have the variances - and like the guys said especially when the time comes to go e85 Cheers Josh

Thanks Scotty, when I pulled the engine down I noticed the stock manifold had a large crack right across the front face just beside the turbo mount position, so we opted for the top mount steam pipe manifold arrives this friday. It was 3 choices buy stock again a crap 1.6mm chinese stainless which have issue's or pay an extra amount for a quality manifold, which to me is a great investment. Many people have issue's with costing on these manifolds, when you way up the cost vs quality and the amount of work that goes into these manifolds then I think well worth it. Thanks again

Thanks for the advice, I have 3 other choices for injectors sitting here - 850cc 1000cc and 1200cc Chequered Tuning will be mapping the ECU and have been working close with 2 other tuners If I am only looking for around 330KW 650cc should suffice - this was advised by a performance injector supplier - but either way when we get closer to fitting I will take everything on board as constructive comments from you guys and also the tuners to see which will be better suited. Obviously we dont want to use something that we dont need to. Thanks Johnny

Hi Ben, I have started to pull the engine down for the new upgrades and noticed some issues that I was not aware of, I guess this is the difference between just having general maintenance and not doing thorough tests. The pressure test between the turbo to the intake manifold passed with no issues. However when I started to pull the engine down removing the intake and exhaust manifold I found that one vacuum hose was split right at the fitting about halfway through the hose. The second one was where the boost gauge Tee's into another vac controlled sensor with a small little crap plastic Tee fitting which was too small for the hose it was into in the manifold - you could basically grab this without any resistance and was a very sloppy fit into the intake hose. 1. 2 x very noticeable vacuum/boost leaks So I guess this was the issue over time as it slowly got worse the leaks were getting worse - hence the bad throttle response. The other issues I found was the - Exhaust manifold had a large split right down the centre front face just beside where the turbo mounts. I noticed this is common Currently have the cylinder head off and ready for the build up of the top end. 1. Aftermarket Plenum 2. 80mm Throttle Body 3. Z32 AFM 4. Top Feed 650cc Injectors 5. GTX3582R Turbo 6. Steam pipe Manifold 7. Cometic VRS 8. 45mm Turbosmart Hypergate Waste gate 9. 340LPH Fuel Pump 10. High Flow air intake 11. Ditching any performance plugs as they are a waste of money and sticking with ngk bkr6e plugs - The copper plugs are more heat resistant at higher boost plus can close the gap up on them all to aid and stop miss fire under boost Already has Large Front Mount, Apexi Power FC, Twin Kakimoto Exhaust Cat Back Looking forward to the new additions and some tuning/mapping to bring it all together. Cheers

Hi Callan, It doesn't misfire or appear to have any spark issues, no backfiring type problems when the surging happens. Im presuming coil pack or spark failure would tend to show signs of backfire issues with excess unburnt fuel, which would cause some form of firing issue. New plugs not too long ago - Gapped to 0.9 - Never changed the coilpacks I'm in the middle of upgrades now and just wanted to try and teeth out this issue before these upgrades. Which also consists new plugs and coil packs as well After reading some other forums - what Ben mentioned about boost/vacuum leak almost sounds like what the issue could be. Not noticeable by ear when driving but obviously when the car ramps up I wouldn't hear it anyway. So I will run some pressure tests to see. Car in neutral would rev to limit with no issue's - I don't free rev to the limit but just an example of how it behaves in free rev - only under increased load and throttle position it has this surging. I'll check the pressure in the system and see for leaks - then post an update on findings

Hi Ben, No from the moment I purchased the vehicle it has always had this issue. I presumed it may have been from the small modifications and not having a re-tune to allow for these mods. I have maintained hosing and connections from the turbo outlet to intercooler to the manifold inlet - but never actually tested any additional manifold area's where it could leak. I'll check this out. Thanks Ben

Hi All, I wanted to share this with you to get your thoughts on any issues which some of you may have encountered before. I will try to be as brief as possible and include as much detail. Subject Vehicle: 1995 GTS-T RB25DET NISSAN SKYLINE Vehicle drives great when under soft accelaration, when I increase accelaration too hard I need to back off because it starts surging, when I back off the throttle until I find that point where it runs great and then continue to accelarate, more noticable when car is under load 40km 4th gear throttle increased - it does this in all gears when throttle increased too much. Current Spec: Apexi Power FC V5.10 ECU Stock Hitachi Turbo - High Flowed - running dual stage Low 7psi High 12psi Stock AFM Stock Injectors Stock Fuel Pump Stock FPR Stock Dump Pipe Stock Coilpacks Large Front Mount Intercooler Aftermarket Air Filter (Pod) Twin Kakimoto Exhaust Cat Back The vehicle does this in either low or higher boost setting - it just appears that it is getting too much air not enough fuel for that throttle position - I have never had the throttle past half way without it doing this. 1. Early next week I will be putting a wideband in to see what AFR readings I get when this occurs. 2. I wouldnt have thought fuel flow and pressure would be an issue running such low boost - stock is 43.5psi with additional 12psi to accomodate boost load which is only 55.5psi that the fuel pressure needs to be when at full boost. 3. Last night I logged the current ECU maps and tested in various load ratings and throttle positions and also logged the data, I cheked this in replay mode but I couldnt see anything major jumping out at me when this surging was occuring. Any constructive thoughts would be great