My 1995 GTR project thread.

[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

[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]

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]

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

[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]

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 !

[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]

will do - tonight if im not too knackered

[gtrjon]

i just got my avcr in the mail too! not the black edition! you should post a diy for install

[JZ]

Yeah, for a country famous for their electronics they seem to be brutal for wiring. My old R32 ( now DJ's car) had an even scarier snakepit under the dash. We pulled apart the console, found a massive bundle of wires and zip ties and was able to start the car by squeezing it. The car was accidentally hot-wired lol.


Posted from my iPhone

[cortexx]

20th july , very late at night .

So its back from the skymeet over the weekend with my head full of all kinds of ideas from everyone elses cars . Car drove there and back ( around 400 klm ) with no problems , no leaks , no vices apart from when we stopped in traffic on the 407 and a horrendous metallic screeching sound came from the engine bay until i turned off the AC in panic . We thought it was one of the turbos blown with the impeller rubbing on the housing , but luckily it was a 12mm socket that had dropped down into the ac fan cage while i was working on it and was rubbing on the blades when the fan spun . SOoooo relieved hah !

So I figure its time to start the grind again , spent an hour fitting an airconditioner in my workshop so i can work without becoming saturated in sweat each evening .

I then decided to pull of the dash cover , glove box and steering column cover to expose the wiring loom and see what i was up against.

Someone had installed a Apexi revspeed meter in the old ashtray location that i wanted gone. Also decided to rip out the toll road card reader thing under the dash and the greddy boost controller and blitz boost gauge .

Talk about pandoras box , WTFARK wiring :-



By the time i had finished i had ripped out about 623452 miles of wire and cut through about 40 zip ties . Who ever had this car before had a zip tie fetish , i swear it was a cobweb of wires and took ages to trace and cut it all out. The loom by the ECU looked like johnnyfives brain . I ripped out all non factory wires leaving only the installed starter keypad / imobilizer module as id like to keep this gadget.

FInally the ECU loom looked oem-ish again :-



It's really un-nerving to find burnt connectors in your dash



this is about half the crap that was floating around under the plastic panels that i removed ... more of this junk to go though !



Finally the dash is de-flowered and its ready to have this installed :-



that will be installed over the next few evenings

[cortexx]

Indeed you could !

[r33gtrrb26]

I would obviously be able to triple coat my stocks once I got them ported as well right? Pretty hot over here in Alberta too.

[RABBIT]

Skyline track day? I would be up for it in about a week or so

way to rub it in ass,hole

[cortexx]

Bruiser is right ..

But for me the cost is not a main issue , a few other things i like about the tubular headers is their ease of install , the cramped working space of the factory manifolds is a contrast to the easy access on the tomei headers , i installed the tubulars with 1 socket , i extension and a 3/8 ratchet handle and 1 wrench, the manifolds require alot more tools and time to install/uninstall.

In my particular application they cost alot more because I spent $600 having everything XMC coated(triple ceramic) to reduce underhood heat and inscrease spool speed and it does work very well.

These turbos are similar to the GT2860-5 garrets , they dont spool up as low down in the RPM as factory units but are at max boost by 3800 rpm and by 5000 rpm you better be hanging on to something , and that at only .75 bar.

I'd have to say that with my current setup i can have the complete passenger side of the engine dismantled in about 1 1/2 hours now. Thats worth a few extra bucks to me

The factory manifolds are the toughest (tubular a known to crack over time) and can be ported to flow really well, though tubular are better for that. Cost wise, there are better ways to make power than that. Ported N1 manifolds and outlets will be great for power even at 600whp. That's technically $1000 or more that can go towards turbo, head mods and other power adders.

There're lots of guys making over 500whp on factory manifolds and head mods, meaning they don't spend huge cash. The gains on the tomei bits aren't as good as what they cost compared to other mods.

Single turbo is the way to go. Less weight, less shuffle, less cost (most times), less lag, more top end, less clutter to work with.