My 1995 GTR project thread.

[ColinR33]

Lol, looks just like mine did! Felt much better after getting rid of the mess! Including my defunct "Ninja" in a box alarm system.

[cortexx]

Well i'm installing my AVCR , innovate wideband wiring and also running some extra wiring ready for my power FC and datalogit this weekend. I'll be attempting to tune this engine myself using my laptop. There doesnt seem to be a guide anywhere to setting up and tuning a PowerFC ECU so i'm going to pioneer this and write up what i am doing with an explanation of whats being changed and why , hopefully ill have some base maps to upload for people with similar setups at the end of it , and will give people enough info to understand and do their own basic tuning before going to a dyno for tweaking by their tuner..

I won't be responsible if you eff up your enigne though (just thought i should add that in) in fact i might even eff my own engine up in the process but as an ex mechanic with 20 years in the computer industry and an extra 6 in the electronics repair field im pretty confident i can get a handle on this

And if my engine performs a mount etna , well i guess ill be rebuilding it sooner rather than later !

[collector240sx]

Have you considered using copilot ?

I haven't used it yet, but I'm going to use it on the RB25det I'm putting in the girlfriend 240sx.

I would at least look into it if you haven't yet. It's neat little program.

[cortexx]

I did alot of reading on co-pilot but unfortunatly i have also read that when someone with programming experience decompiled it that it had alot of ONERROR IGNORE commands used . Prom a programmers perspective and given the trust you need to have in this software im not risking my engine to badley written software.


../edit just looked into it and there is a later version out now , anyone got a download link for it ?


..../edit found it , downloaded the new version and it actually looks really complete , will be trying this out

Not sure if i trust the autotune feature though

[cortexx]

So it's been a busy week , time off with kids and working on wifes VW dune buggy has meant less time for work on r33 .

BUT after liberating the junk under the dash and evicting the rodents I was ready for the Apexi AVCR install.

The car came with a greddy profec version II installed which I am not particulary fond of, the Greddy unit and I had some pretty long mexican standoffs while i tried to tune it and set it up but it is just not what i wanted to use so ..... Apexi AVCR all the way.

The reason i like this unit is control. It has per gear boost control and has a unique way of controlling boost in each gear, plus it has it's self learn utility too for the faint hearted people. It has an attractive display and can give you peak boost/rev/speed displays , graphs and all kinds of other useful info.

So i started off with the easy stuff like installing the pressure sensor. This was located in a safe place next to the vin plate where it wont get too hot.



The great thing about this is that the length of vacuum line to the sensor can be nice and short and does not run all the way into the cabin , it has a wiring loom that runs the length.

next was the boost solenoid , at the moment it is situated in the original spot using the original vacuum lines but i plan to relocate it to use very short vac to wastegate lines soon when i do my vacuum reduction that i have planned.





this leaves 2 wiring lines that I ziptied together and ran in behind the brake booster and into the inner fender . There is a rubber grommet that you can push wiring looms through but it is a tight fit and the way i did this was to push the wiring connector that connects to the display unit through into the cabin from the fender side first as this was easier to pass through. The pull all the other loom through until its all in the cabin. This leaves the 2 small lines running into the engine compartment to the sensor and solenoid.

Under the dash the wiring loom was raised underneath and zip tied out of the way and passed across to the ECU . I then cut the wiring loom on the ECU about 4 inches from the ECU block connector to give plenty of room to add the AVCR loom . I cut each ECU wire , threaded heatshrink tubing onto them and soldered the AVCR wires directly to the ECU loom then slid down the heat shrink and shrunk it with a lighter flame. This will ensure nothing falls apart (wiring splice clamps are fail , dont use them) This was done with each wire. The one exception was the ground and ground reference wire , these 2 wires on the AVCR loom have to both be connected to the ground wire on the ECU BUT you must splice them in on SEPERATE connections . I soldered them into the ground wire in 2 places about 2 inches apart. After the wiring was all done I zip tied the loom back together for an OEM look ..

[cortexx]

The next job was to find a place to mount the head unit that wouldn't look out of place or stupid. I thought about mounting it in a DIN slot in the dash or mounting it on top of the dash but as i was removing the original greddy unit plus the blitz boost gauge that were screwed to the upper steering column cover i decided to mount it there to cover the holes from the previous mounting holes . It looked like this :-





It's in just the right place to see while driving , but not a distraction and when i replace the FAT R33 steering wheel i'll be able to see it all the more easier..

The setup is pretty complicated but i started by setting the target boost to .75 bar and set the gain to 25% so the turbos are allowed to spool up at a safe initial pace. Once this has been set i switched on the self learning mode for all 5 gears , and took it for a drive. You have to actually hit red line in 4th gear with stable boost levels to initiate the self learn mode . Then you can drive around for 1/2 hour shifting and boosting , holding to redline etc while the thing learns.

One thing i did notice is that the self learn errs on the side of safety and increases spool up time alot , when it was finished learning , it was very bland to drive . Safe but so .... unexciting .So i went back into the individual settings.

At this point in the game i had very stable rock steady boost that came on gradually in each gear , i wanted a faster spoolup while keep the rock solid boost control. I switched to the settings for 3rd gear as this is the easiest to run a pull to red line without breaking landspeed records and attracting the cops. When you look at each gears profile , you dont just get to set the boost level for each gear , but you also get to set the boost level for 8 rpm points in each gear. This is great because you can totally program a unique boost profile for the whole rev range.

I wanted to speed up spool , the way i did this was to turn off the learning mode for gear 3 , increase the boost gain to 80% for 1000 - 3500 rpm. This has the effect of closing the wastegates 100% until 3500 rpm is reached , this would normally be bad but with the factory turbos as they would over boost but the tomei turbos dont reach full boost until around 3500rpm anyways in 3rd , so this effectively inceases the spool up speed asap and then the gain at 4000 rpm was reduced to 40% so that the wastegates would open and control the boost stopping it just shy of .8 bar.

I ran this a few times but noticed a slight spike in boost at around 5500 rpm so i corrected this by dropping the gain to 35% at the 5000 rpm stage and this provided fast spool speed with steady boost pressure all the way to 7500 rpm redline.

Then i had to repeat this for 2nd, 3rd, 4th and 5th takes a while and a bit of tinkering but in my opinion its the best control possible for a turbo setup .

[cortexx]

Next up is the Defi gauge set and control unit install , I need a cable to extend the original gauge cable , looked online and its about $25 for a 3 ft one so tommorrow ill take one of the short ones , cut it and solder in an extension loom . ill post an update with pics when their all installed

[r33gtr]

Let me know when you get rid of your steering wheel ! I'm looking for one for my car. Leather on it is all worn .

[cschepp]

Cortexx your awesome buddy. You and your family are very nice peopled. You are all welcome anytime!

Oh and btw. I did as we discussed and cleared things out and took it for a spin. Runs alot better! Thanks man

[cortexx]

GJ Chris , thanks for the kind words , i might have to rent your shop hoist one weekend to swap a tranny sometime in the future , i used to do them on my back years ago dropping them down onto my chest and rolling them sideways but i have a hunch this tranny might squash me . I'm also tossing the idea of a carbon fibre drive shaft to reduce rotating mass and improve response and hopefully drop some weight got some home work to do there ..

[cschepp]

Rent it, what for. Come down let's have a few pints and we can do it. Wouldn't be bad except you might have to crouch down a bit under the hoist as your pretty tall man. But ya your more than welcome to drop by anytime Paul!

[cortexx]

OK got into the workshop and threw the car back up on the ramps tonight with the full intention of installing the wideband sensor wiring.

I have decided that because i have the wideband bung welded fairly high up the downpipe and can see it from the open engine bay that i'd run the wiring for the lambda sensor across the back of the firewall and through the rubber grommet inside the drivers side inner fender. The other option was to drill a hole int he floor of the passenger side to pass the wiring up and i wasn't too happy about doing that.!

I occured to me at this point that i should work too pass all further wiring through at the same time because i also have a defi oil pressure , oil temp , water temp , boost and fuel pressure sensors i have to run .

I therefore decided to install the GReddy oil filter relocation kit i have had kicking around to give me the 2 holes for the oil sensors ... funny how some jobs sidetrack you eh ?

So removed the filter from the HKS oil sandwich plate which meant i promptly dumped about 2 litres of oil all over the workshop floor because i wasnt paying attention and didnt relalise the filter being lower than the cooler would mean it would syphon its contents out of the filter block , handy way to drain the cooler though i guess lol.

I threw cat litter under the car to soak up the oil and proceeded to install the GReddy plate and stainless braided hoses . This kit comes with the most god aweful hose ends , they have screw clamps hidden in a fake anodised earl cover - really crap stuff , ill be changing these later and making some black hoses to do the job with russel fittings ( my favourite )

eventually this is where i got :-



Of course the instructions that come with the kit are written on a piece of toilet paper using Japanese hyroglyphics again so its up to me to figure stuff out using common sense and experimentation.

The bracket that comes with the kit mounts the oil plate and filter just forward of the fuse box which is awesome in a factory unmodified car , but in my engine bay with all the crap iv'e changed it's not gonna fly , the RIPS oil catch can rears its head again to get in the way so mods must be made .

this is a pic of the bolts im supposed to use to mount the bracket , which of course means the filter would foul the catch can !



It's kind of amusing to note that all the tuning companies take great pride in making bolt on kits that are easy to install , but none of them realise that their kits sometimes have to co-exist with other mods and that nothing really fits right out of the box lol .

Anyway I decided to kill another bird with this stone and do a better job of mounting the boost solenoid on a bracket that will also mount my oil filter assembly . I did use the GReddy bracket but instead of bolting the remote unit directly to it , i used it to anchor an aluminium bar to the inner fender ... - mad scientist at work



this was the old boost solenoid location -



This is the new bracket i fabbed from a nice piece of aluminium bar



At this point in the game i couldn't situate the filter mount where i wanted because i had too much braided line sticking up from the sandwich plate on the engine so i spend about 1/2 hour trying to reef off the hoses so i could trim them , my poor fingers - did i ever say how much i hate braided steel lines ?

After chopping about 3 inches off each line with some weiss tin snips the filter plate mounted up , i bolted on the boost solenoid and it looked like this :-



I'm a great believer in clean looking installs so this looks good to me , i threw the filter back on and it all looked on , even clears the hood when i close it



and with the boost solenoid remounted on the same bracket :-



At this point Im now ready to run my defi sensor wires along with the wideband loom into the car through the big grommet inside the drivers inner fender , I have to find a location fo the water temp sensor and might end up cutting one of my hoses and inserting a sensor adapter.

I emptied the catch can tonight after about 1500 klm of semi spirited driving and there was practically nothing in it , no oil just a little bit of condensation and tiny amount of sludge . This is a good sign that my engine hasn't got much blowby , going to dump the oil and fill again this weekend , I have been running 10/30 redline , oil temp never goes over 80c , was contemplating a slightly heavier oil because of the hot weather but not sure if i really should .

Should have my datalogit here tommorrow and i have co pilot ready on my laptop ready for some powerfc fun once all the vital monitoring stuff has been mounted Then i'll start on the fuel system .

time for bed (yawn) !

[DJ]

Looks good! You really need to do something with that intake manifold! the finish looks real rough!

[cortexx]

Its being replaced

[GTRADDICT]

Its being replaced

Oooh! By what?