mawzy

Does anyone have any insight into response changes with a .7 or .63 rear housing? like say really only looking for that extra 30-50hp, but don't want to compromise response too much either.

So going to turb specs from website, compressor spec 54/77mm 49trim Forged CNC Aluminium, centre housing MP350c, 360 Thrust, LI journals, Water cooled. turbine spec 59/70mm 71trim 12Bld, and finally the different ar options available T3 .48, .63, .7, .84, .94 Hope this makes sense to the technical savvy out there. Any opinions /thoughts appreciated

THanks for input. Tuner didn't say anything about pinging, but wasn't making any more efficient power increases. This particular turbo does come with a .63 rear housing option, which I discussed with the seller at the time. He was good to deal with and seemed knowledgeable. He knew this was going on a 25det motor, and yes as stated probably correct, he would have been rating at motor which I hadn't thought about. Tuner recommended going to a garret turbo, which they claimed would push up to and a bit over 500hp. Another much more cost effective option would be to change to the .63 exhaust housing with this turbo, and he said they're direct bolt in out options for the exhaust pipe. But do you think would be a worth while move, or is this not worth pushing any more? My original hope for setup was around 450-470 hp mark.

Hi all, so after a long twisted journey car has finally had a full tune and up and running. Just after some people more in the know what they think of power results, and the dyno printout. I'm a bit unsure about the power delivery over 4000rpm how its a bit up and down. I thought it should be smooth, and that this would be a tunning issue? ok so list of mods Rebuilt 25det neo- arp rodbolts, metal shim headgasket, upgraded oil pump, heavier valve springs, new rings bearing etc, extended sump Greddy style front face intake 660cc injectors factory fuel rail nismo regulator nismo intank pump greddy type r bov 3inch pipe to intercooler Gtr style intercooler 3- 2.5-turbo intercooler pipework Masterpower turbo .48 exhaust housing, .54 compressor (I think or .5) sinco high rise manifold turbo smart 40mm gate full 3 inch exhaust, with venom 500 series cat, and adrenalinr high flow muffler catch can, venting into intake pipe 4inch intake with k&N pod the intention was to build a tidy responsive st package which I seem to have achieved. Tuning wise, the cam sensor was giving too sensitive reading at high rpm, so changed to a 24 tooth trigger wheel. But once fitted they only did 2 more power runs before pulling car off dyno. And the setup apparently reached it's peak at 16psi, and 432hp, saying the turbo was becoming a restriction or the exhaust. I'm confident the exhaust isn't the restriction, and knew the turbo was going to be the cars main limiting factor, but the supplier rated it to 20psi, and 450hp. So basically do you guys think numbers match the package, and are the dyno fluctuations a normal thing? Link plug in ecu

Siemens. When I bought the computer the tuner recommended them. I still needed a set, thought he wouldn't suggest something they weren't getting good results with. He did recommend standard replacement r35 injectors, saying they were bolt in 560cc I think, but were twice the price. I'll see what happens, hopefully don't need to adjust anything. Also forgot it's Bathurst today, haven't watched whole race for couple years now, but like to watch some of it.

Pretty confident with the fuel side not leaking. I've also installed an oil cooler, I made the braided lines up so bit anxious about them. And installed a radiator header reservoir, there's ended up a few very hard to reach hoses associated with that under the plenum. and oil/water lines around the top mounted turbo. Touchwood, I've taken my time, and had a bitta experience with cars, but this car has alotta money tied up in it. Would be a bit let down if I fail at the end hurdle. All going well will finish the ecu pre start checks tomorrow, and look at firing it up. Also the way I understand it there's a scaling option associated with the fueling tables? We could adjust this to help idle without changing individual values? Cheers

Yeah has worked resetting the ecu. I'm not sure if we'd changed some oddball setting somewhere else but it wasn't coming up like the screenshots you guys have taken. It is now. I'll leave now for sparky friend to come help. Thanks for your input and advice. One more q for everyone. The base 34 tune is for a standard car correct? Will I be doing any harm in running my car with it? Again will just be idled, not driven. It's running 666cc injectors, which I'm assuming will over fuel quite a bit. Cheers guys

Thanks for the help guys. Yes that is the screen we're in, but there's no option to change the type of map sensor. Another thing i'm wondering is if I've downloaded the correct software. The links a couple days old so I assumed it's the most up to date firmware g4. The other possible issue, is we tried the calibrate map sensor before realized had to select the correct sensor, so also going to try restore and start again. Will update how we go. Thanks

Thanks guilt toy. I'm pretty sure this is what we are bringing up and it lists off all the inputs. But clicking on the map input brings up parameter properties, but there's no option to input what map sensor is installed. Are we missing a step before this? or should we be looking under another input? Have tried all the ones we thought were relevant, but brings up the same screen. We have selected the base map for standard r34 gtt. Again thanks for any help anyone can offer.

Hi all, just looking for a bit of help from anyone familiar with the latest g4 software to help us get started. Firstly my intentions are to simply run the car at idle, check over for any issues, ( I've assembled the engine, a factory motor with bolt ons) and will then be taken to a tuner to be dynoed. My auto sparky friend is doing the work wiring wise, and we're using an r34 g4 plugin ecu. He has done this previously with wire in ecu's using slightly older software. Where we've come unstuck is setting the initial parameters for the ecu, i.e which map sensor, tps, timing etc. Can anyone point out where to bring down the anologue input tree? We've been clicking options - setup ecu parameters - which brings up anologue inputs. But we can't find the right options there for selecting the correct map sensor just options to setup limits of sensors. Any insight or input would be greatly appreciated. Again, we won't be tuning the car, simply running and checking over for leaks or issues, which I'll sort before dropping to tuner. Thanks

Hi all, done a bitta looking around on forum, found similar threads and issues, but couldn't quite clear up my uncertainties, so thought would start this topic, and get peoples input. I'm doing a Bolton upgrade to my r34 25det neo. Reasonably mild street setup, hoping to achieve 400hp. For the intake I'm using an imitation greddy plenum, and have adapted my factory r34 aac valve to suit. Due to needing more water feeds/returns (I'm not totally sure which way water flows etc so some clarification on this would be good too.) I've tapped 3 new 'feeds' into the manifold approximately where the factory ones are above the water jackets coming out the head. ( I've attached a poorly drawn picture of the whole setup) Can anyone see any immediate issues with flow from what I've done? I've tried to stay as close as I could to factory setup, but using the header tank instead of the bleed valve at the front factory intake. If there are no issues anyone can see, my main query is with the bottom of header tank and where I should be feeding that? Should I run it back into the connector on the thermostat housing? Or there's an unused bung in the radiator I could use a fitting in, or I can put a pipe into the radiator hose and feed into that. What do people think would be best option there? Also the aac valve has 3 fittings, At this stage I've blocked one off, is this gonna be ok? And the way I've drawn it have I got the connecting the right way? Thanks for your thoughts and any input will be appreciated. Rb25det water flow.pdf

The tuner didn't say I have to go to a link. They were fine with pfc, and actually commented that they are usually straight forward and reliable to tune. He recomended the link as alternative, albeit a costly alternative. I would still need to buy a zx airflow, here they're roughly 200-300 second hand, or 500 genuine new. That cost, plus my original purchase of pfc is starting to get close to price of a g4, so if I can onsell pfc, I'll look at link, otherwise will do the 3inch reduction to a zx airflow meter.

GTSboy, thanks for the info. At the end the day I'm shovelling shit uphill really. I went had a chat with a local tuner today, he also didn't recoment changing airflow meter size. Didn't go so far to bag the pfc but recomended using a link ecu, which is an option I like and would do, but I already have the pfc, and link will stretch my bidget a bit farer than I'd like. There's no real rush here, so will take my time a bit, see if I can on sell pfc, or will make the intake 3inch and stick with zx airflow. thanks for all your inputs.

It's a masterpower turbo, mpr 545, with a smaller .48 exhaust housing. Being a street car, response has been a big consideration. I'm hoping it'll push get around the 400hp mark, wether i get there or not is yet to be seen. Supporting mods, apexi pfc nismo fuel pump, denso 650cc inj, imitation greddy intake, Sinco exhaust manifold, greddy bov, Gtr intercooler, 3inch pipework all round. Just had a look aswell its actually a vh45 airflow meter, if this helps my case. It looks like it's a 3.5inch diameter caseing.

Thanks for all the info and details. I was under the impression putting airflow meter in IC pipework has a whole set of it's own issues? And just wanting to clarify some points. So the airflo meter will alter it's output depending on airflow, and as you're saying takes into account for density and temp to an extent aswell. At it's lowest output it'll be idle and x amount of air will be going to the motor. At full noise it'll be ready max output, with max amount of air passing it. I would have thought the ecu uses that info and have the corrections for fuel timing etc. So by putting into a larger diameter pipe. Yes definately more airflow, but still the same scale, idle will be lowest airflow, full noise will be the most. So the ecu is getting signal from least to most airflow, is it then not up to the tune and tuner to compensate the extra amount of air when tuning by adding more fuel and ignition? All this in mind, I'm no expert or tuner, and don't plan to do this myself, I'm just trying to clarify in my mind, There might be things I'm not taking into account or thinking of.

Don't think there is an option for a map sensor with this model pfc. I thought that was just the d jetro model. It seems like the zx meter is a better option? Is there a reason why the actual sensor can't be retro fitted to the 4 inch pipe? Will this cause other issues?

Hi, yes I think you are correct has the anti surge slot etc around it. I might have made the mistake here and ordered 4inch join and pipe to suit then. And are you saying it is ok to use a sensor in a slightly bigger diameter pipe like I'm suggesting? No I won't be tuning this, and no I won't be driving round on it before it's tuned. Just wanting to do as much of the spanner work that I can to save some dollars.

Hi all, just doing some upgrades to car and wanting to see what ppl think after hearing few diffrent opinions. I'm topmounting a new turbo which has a 4 inch inlet to my 25det, (along with supporting upgrades). I have an apexi pfc to tune with, and as far as I'm aware you can use any nissan airflow meter with these. Is that correct? I have the factory airflow, from what I understand that will become a restricting factor and want to upgrade this. I have a vh41 airflow meter but I've been told they're not as good as a 300zx meter. What are ppls thoughts and facts around the two? Another thing I'm looking to do is cut the sensor out of the tube housing, if that makes sense and direct fit it to the alloy intake pipe. In doing this does this give me other options? Is there any reason I can't use the factory 25det sensor in a 4inch pipe? It'll still be reading air speed but there'll be more quantity at any one time. But having a complete tune, will this not be accounted for? Any thoughts , advice, opinions will be greatly appreciated.

Wen I did mine, I only cut away panel work around the top of wheel arches, then tapped the inner gaurd up to it and rewelded to the skin. I test riveted new skin on to get alignment right and maked where it met the bodyline and needed blended. Took gaurd off, then peeled the paint off at the joining points, and ruffed the metal up to key the glue and fibreglass. Can't really remember what glueI used. Something that doesn't expand as it sets, and rivited on. Left for a good 1-2 days to set, then keyed the fibreglass panel, and fibreglassed quite a thick layer onto the panel and car, so there was plenty of "meat" to sand flat, meaning I didn't need to put much bog in. Just to fill couple lil bubble holes as I sanded glass back. That was all done 2 years ago with no cracks to date. Was a very time consuming job, but looks factory all finished. Much tidyer than the riveted on look.

Depending on what doesn't fit'line up it might be as simple as trimming exta material off, or cutting and reglassing sections together. One comment I will disagree with is baking fibreglass. Yes this can be done, and I'd assume most places would do this way, but yes it can cause issues, esp with cheaper stuff. Opening air pockets in the gelcoat that aren't seen before the bake.

A professional body shop wouldn't take anywhere near that time frame to actually do the work, keeping in mind they have spray booths and bake the items. When we sprayed my car through a friends buisness we were in at 7am, and done by 12. Takes 30min to bake, and we buffed it 3-4days later. It'd be more about workloads, As a buisness you'd want to have work booked up for a good 2-4 weeks, if not longer, especially having a few workers. Ya don't make money having workers do nothing. Another option in your case if the items are genuine parts is just dropping them off to paint without the car. Being genuine they won't need additional work to fit the parts. Or you could just line the parts up yourself. Skirts will be easy to check (just make sure you have them on the right sides of the car very similar both sides but definately only one correect fitment ) And with a bitta diy knowledge testing the front bumper isn't the hardest job. Imitation parts, depending on your experience, it would pay to have the final installers do the test fitting.

Just to clear up, you don't need to change your headlights, they are the exact same. I've done this conversion. If you use all genuine parts, you will need, gtr front bumper, fenders, bonnet, bonnet catch, bonnet hinges. (the last two are diffrent between gtt and gtr) Where the gaurds mount in the engine bay you'll need to space up approx 20mm with spacers. Also using factory gear, you won't have issues fitting and lining parts up, so would be an easily acheivable diy job. Again with spraying, depends on your own personal experience/competency. If you go to the extent of whole car you'll be looking at alota dollars to get genuine rear quarters bumper skirts, fuel flap taillights. I did mine all out of fibreglass, only diffrence is mine slightly wider due to the type of rear quarters I used. Fitting these was very time consuming, but of little cost doing myself. I imagine paying to have done will add up quickly. Hope this helps and gives you an idea of whats needed/involved

For all the parts i make, can do at $1800NZ plus shipping (unknown) You would need to source bonnet and front fenders. If you aren't fitting and painting yourself, I would allow more than $300,

No I'm a builder by trade, skylines just my hobbie/interest. Had 32, and 33, always done as much work etc myself, otherwise wouldn't be able to afford. But was lucky enough to get access to a spray booth for the paint. Everything else has been done in my garage Stupid arrogant GTR owner.

Just finished making and doing this to my GTT. Very time consuming process but well worth the hard work and end results. I've made molds off a GTR, so can make more peices if anyone wants/interested in them. (I am in NZ though) Can make the gtr front, sideskirts, rear bumper, nismo skirts/caps, wide rear arches (not identical to gtr slightly wider). I used genuine front gaurds, and sourced bonnet and spoiler. As i say alott of work but the end result has been worth it, very happy. Couple pics for those interested.