[Power FC - Ignition not turning off?]

Power FC Installation - Ignition not turning off?

 

Hey guys,

I recently installed an Apexi Power FC on my R34 GTR and I eventually got it to self calibrate to a stable idle although when I go to turn off the ignition, the engine continues to run for another ~10-15 seconds (stalls itself) and the dashboard lights remain permanently on. The only way I can turn the ignition off is to disconnect the battery. If I remove the Power FC and re install the stock ECU everything is fine and the car's ignition turns off like normal.

 

Anyone have any experience with this problem or know a possible fix? 

Cheers, Nick.

[Power FC Installation - Ignition not turning off?]

Power FC Installation - Ignition not turning off?

Hey guys,

I recently installed an Apexi Power FC on my R34 GTR and I eventually got it to self calibrate to a stable idle although when I go to turn off the ignition, the engine continues to run for another ~30 seconds and the dashboard lights remain permanently on. The only way I can turn the ignition off is to disconnect the battery. If I remove the Power FC and re install the stock ECU everything is fine and the car's ignition turns off like normal.

 

Anyone have any experience with this problem or know a possible fix? 

Cheers, Nick.

[Safe boost levels for -9 Equipped R34 GT-R]

4 hours ago, ActionDan said:

Remember PSI is just a pressure reading in the manifold and tells you nothing about the actual air flow being put out by the turbo/ingested by the engine. 

For safety sake, you will want to put it in a dyno at a bare minimum and not be getting into boost until you do.

Make sure the AFRs are safe. As -9s are a step up in size compared to stock, they flow characteristics are quite different. 

Usually, people do turbos with an ECU/injectors/pump etc as you can't make good use of the turbos otherwise. 

Are the current turbos actually stuffed? Minor chips in blades is not a big eal at low boost and could allow you to get the other bits together and do it all at once properly. 

 

Yeah the old ones are pretty far gone :/. I might just install the -9s then and keep the car off the road for a little longer until I can get injectors, ecu etc. Thank you for you help though

[Safe boost levels for -9 Equipped R34 GT-R]

10 minutes ago, ActionDan said:

Compressor map shows 22-psi is about max efficiency.

https://turbochargerspecs.blogspot.com.au/2011/03/garrett-gt28r-gt2859r-56-trim-310-hp.html

Approx 2.5 Pressure ratio on the graph.

HOWEVER, people argue that the limiting factor to the turbo's longevity is actually the turbine flow/heat and as you can see from the graph, the turbine starts to choke before the compressor does. Choke = heat, heat = premature wear etc. 

So how hard you run them depends on the type of usage and your appetite for risk. 

20psi should be fairly "safe" on both fronts, but 22-24psi squirts are not going to hurt a healthy turbo in a street application. 

Other variables come into play here also, fuel type use? E85 has lower EGTs = happier turbo. Size of dumps and exhaust? Bigger = more flow, less backpressure and less work for the turbo. Etc etc. 

We ran out of fuel pressure on the dyno at 373kw at 20psi on -9s in my car so this week we should see if it will happily hold 20-22psi. Keep in mind this is with N1 manifolds, 3" dumps into 3.5" exhaust, E85 and Kelford L182A cams (springs and head studs for insurance) with pods (proven to make more power at this boost on the dyno) and a Plazmaman intercooler. 

To run 20psi+ on these turbos you will also need fuel pump, injectors, an ECU to make use of it all, and quite likely AFMs if you stick with those rather than going MAP (which would also mean needing a MAP sensor). 



 

Cheers for the quick reply Dan, I appreciate the effort too. Yeah I plan on getting injectors, ECU and a fuel pump later down the line but I will definitely keep this in mind . In regards to running the -9 turbos on my current stock setup (stock injectors, pump etc), should running 0.8 bar be safe in terms of fitting within the stock injector's/pump's limits? even though it seems as if they were maxing out on the old stock turbos?

[Safe boost levels for -9 Equipped R34 GT-R]

Safe boost levels for -9 Equipped R34 GT-R

Hey guys, 

I recently purchased a pair of GT2859R -9 turbos due to the stock ones having blade damage and needing a full rebuild. I was wondering since the new turbos provide more flow, what boost levels would be considered to be 'safe' on a completely stock RB26? I previously ran 1.00 bar on the stock turbos and the car seemed to run fine although I did notice the injector usage getting close and hitting 100% which makes me slightly concerned for the new turbos. Do you think the stock boost of 0.8 bar would be fine or possibly even less?

Cheers, Nick.

[R34 GTR - Misfire/Stuttering]

On 2017-4-25 at 0:39 AM, squareznboxez said:

Have had similar issues in the past.....

Thank you for the reply. That does make sense now that I think about it . I will get in contact with a tuner within the week coming and I have had air leaks in the past so I will make sure to inspect the whole system properly.

Again cheers for the help, Nick.

[R34 GTR - Misfire/Stuttering]

R34 GTR - Misfire/Stuttering

 

Hey guys,

Over the past couple of months I have noticed an increase in misfires while coming on boost/just before boost. Initially it was mild yet when it happened the 4WD and A-LSD error lights would toggle on in most cases. Now every time the car is driven I experience the misfire.

The coil packs and spark plugs were swapped out for new ones just under a year ago so my initial thought was that it could not be them. Boost is also very inconsistent in when and what boost it hits. I also noticed that in 2nd gear for example, there is barely any boost (0.4-0.5 bar) before 4.5k rpm and then at around 5k it hits really hard (1 bar) and causes the car to jolt suddenly. I do know that the stock turbos currently installed are in poor shape having a whining noise so I wasn't sure if that had anything to do with the problem but I am planning to swap the turbos out next week hopefully.

Has anyone had something similiar or know of a fix?

Thanks, Nick.

 

[R34 GTR MFD - Throttle Percentage Unstable/Erratic]

3 minutes ago, 89CAL said:

What happens at full throttle? Can you look with the car off (as less vibration etc so less chance your foot is moving small amounts)?

What is your battery voltage like?

At full throttle (while driving) the MFD percentage readout still jumps from (100%-99%-100%-98%-99%-97%-100%) very rapidly. With the car off but in 'Accessory mode' the readout on the MFD is very smooth without any kind of jumping or hiccups and is very accurate to the position of the throttle. I did notice that when I am measuring the voltage of the TPS, it drops significantly when I start the car which tends to trigger the '4WD/a-lsd' error lights on the dash so for the moment I have set the TPS voltage higher than the 0.5V (closed throttle) recommended. The Battery voltage on startup is around 13.6V which I think is low compared to what I normally see which is at least 14.2V.

[R34 GTR MFD - Throttle Percentage Unstable/Erratic]

R34 GTR MFD - Throttle Percentage Unstable/Erratic

 

Hey Guys,

I have noticed during the last few weeks that the MFD throttle percentage display has been noticeably erratic in which the readout is jumping +/- 3 or so percent (flashing almost) while the throttle is steady. I replaced the TPS and the problem continues. While the car is not running but in 'On'/'Accessory' Mode the readout is smooth and steady with no fluctuations at all. Does anyone know of a fix/solution?

Any help is appreciated, Cheers

Nick.