upping the boost

[BrooklinsFinest]

After running the '33 almost stock for the last two seasons (other than the tein ss c/o's gpower medallion titanium turbo back, and an exedy twin plate) and having no problems other than popping a boost coupler last summer, I've decided that this is gonna be the year to up the boost a little. I'm thinking about going with an apexi AVC-R and a power fc? Is anyone running this setup, or does anyone have any recommendations?

[r33_gtst]

The power fc is a full stand alone system that replaces your ecu so complete tunin can be done. With the bolt ins you have, the pfc would be pointless. On the 33, these turbo's act up after 12-13 psi and their longevity is comprised.
Whenever you turn up the boost by 1 lb, your changing the air/fuel mixture. Some people will crank the boost and run their car not realizing that it's the equivalent to running your body and drinking little water. You will scrape by, but eventually dehydration will catch up.

Your best option would be a boost controller and a piggy back system like the greddy emanage. You keep your oem ecu and it allows you to up the fuel, ect... I also believe the emanage has a two step in it also. Another option is getting a flashed or chipped ecu but that's the cheap way, if you want to keep the car, invest in some good products.

[BrooklinsFinest]

I have an emanage blue from a previous car, but I've heard negative things about them. The only thing I would need to get to tune it properly would be a wideband. Whats your feeling on the avc-r?

[Michael1992]

why don't you save the money and just go get the car tuned somewhere its like $600 and buy a AFR wideband and you're good to go. save the $2000

[BrooklinsFinest]

I was on the Greddy website looking up the guides and I was surprised to see that they featured all of the Nissan straight 6's in their original install guide which raised my confidence in installing this in the car. The last time I used it was to adjust a/f and spark when I installed a JDM fs-ze in my old P5. I already have all of the harness and PC cable just sitting in my garage, so I might as well install it and get it tuned. I guess the next step is finding a decent electronic boost controller or deciding if I just save some money and go with a manual one.

[r33_gtst]

Don't get a manual boost controller
If $ is tight, get the HKS evc S
It's small, affordable and a quality boost controller

[Skym]

It is a piggy back controller that changes the signals from ECU. If stock ECU is not detecting knock it will stay on main ignition, fuel maps and will get a decent tune. But if stock ECU detects knock or excessive noise (It thinks engine is running on lower octane gas) during tuning it will switch to knock / low octane ignition, fuel maps. This becomes a problem when tuning with a piggyback, as the timing, fueling changes by alot and ruins the tune and is why most don't use piggybacks.

A standalone ECU like Link G4, ViPEC ECU, PowerFC, modified internally 300ZX ECU (with Nistune installed inside) so it plugs into stock loom (cheapest option) are the best ECU's to use on a RB25DET.

If you buy Link G4, ViPEC ECU, PowerFC, they have onboard boost control (don't need to buy a boost controller, just the boost control solenoid that plugs or wired into ECU). I think with Link G4 they use the MAC? brand boost control solenoid. Also Link G4 has motorsport features like anitlag, launch control, can run crank trigger CAS setup, etc.

If have R33GTR, stock R32GTR ECU (Nistune installed) + stock R32GTR o2 sensors can be used.

[NismoS-tune]

Manual boost controllers work fine and in most cases better than electronic. The reason people use electronics is for on the fly changes or multi stages.

Manuals are cheap, robust and are set/forget. Don't need to worry about playing with it.

You don't need a stand alone either for minor boost gains. Most ecus can run more boost without tuning. I'd get a tune if I were going over 1 bar though just to be safe but I've see and done 1.2 with good afr on stock evrything, no prob

[quadracer111]

Manual boost controllers work fine and in most cases better than electronic. The reason people use electronics is for on the fly changes or multi stages.

Manuals are cheap, robust and are set/forget. Don't need to worry about playing with it.

You don't need a stand alone either for minor boost gains. Most ecus can run more boost without tuning. I'd get a tune if I were going over 1 bar though just to be safe but I've see and done 1.2 with good afr on stock evrything, no prob

I agree. Hallman mbc's are really great.

[Skym]

Depends on the electronic boost controller you use. From what I understand, some electronic boost controllers use rpm, throttle position, speed to control how fast boost builds and can drop boost level if car wheelspins, etc. Also doesn't take long to setup throttle position, etc. Base settings for everything else seems to work ok if keep on lowest boost level you can run until retune. But boost controllers should be setup properly on dyno with wideband to monitor A/F ratio and tune to match if possible.

Engine should be smoother, more responsive with a retune. I wouldn't run higher boost levels with stock tune, as it goes very lean at lower rpm's and stock ECU probably will pull ignition timing, dump more fuel in to prevent knock. At higher rpm it's usually safe. With RB25DET it's a recipe for disaster being a higher compression engine, as can take out ringlands / side of piston. ECU tune is the key to keeping RB25DET pistons in one piece.

[BrooklinsFinest]

Thanks for the info guys- and btw I drive a '33 gtr.. so the RB25 stuff doesn't really apply - good points either way, thanks

[BrooklinsFinest]

I found this on http://nissanskyline.6te.net/tuning_GTR.htm :

Boost increase
Boost should not be increased above 1 bar with the standard GTR turbo’s because the ceramic exhaust wheels will fail if to much heat is produced. The N1 GTR is equipped with larger turbo’s with steel wheels in this case you can run 1.5 bar, efficiency runs out above this boost level. The good news is that GTR's are equipped with a boost restrictor from factory and once this is removed you can run 1 bar of boost. To do this locate the yellow banded hose which is connected to the boost solenoid, there will be a lump where the yellow band is, remove this restrictor and you will have 1 bar of boost. Alternatives include a electronic or manual boost controller.

Should I remove the restrictor after the emanage install?

[Skym]

Higher boost level = higher shaft speed on turbo. If turbo is old it can be off balance, so higher boost levels with higher shaft speeds just make the shaft go off balance more. What usually causes the off balance problem is lack of oil to bearings due to coking / dried oil deposits (high oil temps when thrashing on racetrack or turning engine off before oiltemps drop to a safe level after thrashing car), age / wear. Usually happens on compressor side, but sometimes it happens on exhaust side (hot exhaust when thrashing doesn't help with oiltemps) which results in exhaust wheel going off balance, hitting exhaust housing and going down exhaust (usually in middle of exhaust). If backing off throttle when it happens, some ceramic fragments go back into engine and score the bores, etc.

Air to oil engine oilcooler is must have mod to prevent the above from happening on GTS, GTR models. RB26DETT, RB25DET have a coolant to oil oilcooler, but it's usually not enough on racetrack with boosted up engine.

Some say the ceramic exhaust wheel is held on by glue and this could fail with high exhaust temps which occur when engine is leaned out or I think was running too rich with retarded ignition timing. Running engine rich, using correct ignition timing can help to prevent this from happening. But never seen proof of this failure, only experienced the above failure with bearings failing on compressor side of turbo and compressor wheel touching compressor housing due to high oiltemps, coking that blocks oilways to bearings inside turbo (lack of oil).

If have stock R32 GTR ECU with Nistune, boost control can be done via ECU (boost duty map).

From what I understand, boost restrictor is there to help the boost control solenoid control the boost level. I would do it via ECU.

[cooke24]

power fc that ****.

[BrooklinsFinest]

ya I pretty much just street drive the car, I've never hammered it for more than a minuet and I always warm up and cool down the car properly. I've had a couple of fully built cars in my day, and it was never my intent that this will become another one of them, but then again only time will tell. I'm just gonna run the emanage and a manual boost controller and get the car tuned this spring, maybe a set of Tomei Poncams closed to the summer. IMO I need to tune the car for Canadian gas anyway, seing as I have an emamage thats not doing squat, and a good MBC is less than $100- might as well just get the tune done and see where it goes from there. Besides, I promised myself I'd do brakes and tires before I spend any money on mods this year. =P