Tuning AEM EMS V2
09-22-16, 07:49 AM
#1
Lexus Test Driver
Thread Starter
Tuning AEM EMS V2
....Starting to setup this AEM EMS V2 on my 92 SC300.
I've gone over most of the base parameters so far and I think I've got a decent starting point. I have a few questions regarding fuel and ignition map (generalizations), and also the rev limiter.
REV Limiter---- do you want the ignition and fuel cut to happen at the same RPM? These can be set independently. I would think you would want them to cut at the same time- if you cut fuel first then you momentarily go lean? If you cut ignition first then you've got unburned fuel? Which is better?
Fuel Map ---- I'm on BC 268 / 270 cams on a ported head with HD valve springs. It flows very well up top. I would imagine the large efficiency island (peak torque) centered around 4500rpm on a normal 2JZ in my case would be moved up 1000rpm or so? 2000rpm higher? I've always thought that with stock compression, I would need to run more fuel - perhaps 11:1 AF ratio as a target on pump gas. Thoughts?
Ignition timing --- Same as above- I'm assuming the hotter cams also move up the band where I have to reduce timing a little (under boost). I'm thinking the timing needs to be around +5 degrees (or even 0 degrees) in the area around 5500rpm under full boost (I'm tuning for a 10:1 compression motor and 10lbs of boost initially). I think it also means that I can run more timing at lower RPM below around 3800 because of the cam. - there seems to be more detonation margin down low with the hotter cam.
I'm setting the rev limiter at 8500rpm once it gets stable. Before then, I'll stick to 6200 or so.
Last - if any one has a .cal file for a 2JZ with hotter cams, I would love to see the fuel and timing maps. Could even just be a screen shot.
Thanks.
I've gone over most of the base parameters so far and I think I've got a decent starting point. I have a few questions regarding fuel and ignition map (generalizations), and also the rev limiter.
REV Limiter---- do you want the ignition and fuel cut to happen at the same RPM? These can be set independently. I would think you would want them to cut at the same time- if you cut fuel first then you momentarily go lean? If you cut ignition first then you've got unburned fuel? Which is better?
Fuel Map ---- I'm on BC 268 / 270 cams on a ported head with HD valve springs. It flows very well up top. I would imagine the large efficiency island (peak torque) centered around 4500rpm on a normal 2JZ in my case would be moved up 1000rpm or so? 2000rpm higher? I've always thought that with stock compression, I would need to run more fuel - perhaps 11:1 AF ratio as a target on pump gas. Thoughts?
Ignition timing --- Same as above- I'm assuming the hotter cams also move up the band where I have to reduce timing a little (under boost). I'm thinking the timing needs to be around +5 degrees (or even 0 degrees) in the area around 5500rpm under full boost (I'm tuning for a 10:1 compression motor and 10lbs of boost initially). I think it also means that I can run more timing at lower RPM below around 3800 because of the cam. - there seems to be more detonation margin down low with the hotter cam.
I'm setting the rev limiter at 8500rpm once it gets stable. Before then, I'll stick to 6200 or so.
Last - if any one has a .cal file for a 2JZ with hotter cams, I would love to see the fuel and timing maps. Could even just be a screen shot.
Thanks.
09-22-16, 04:34 PM
#2
I like to have ignition cut far after fuel cut. Rely on fuel cut. Going rich is relatively safer than going lean.
That fuel "island" you refer to is really setup and turbo dependent. Someone who has more experience may be answer your question more directly but I think the best answer will depend on what your datalogs show. Ever setup is different. Cams do move powerbands right but it is really more affected by the turbo you are running. In my experience on my 1JZ going from stock to 272s on the same 60-1 turbo, that "island" you refer to didn't actually move at all. I just had less drop off of that island when approaching redline. If anything, island actually started slightly earlier.
Timing? Just add a degree and log a run. If your knock counts go above 3 back off. Rinse and repeat.
That fuel "island" you refer to is really setup and turbo dependent. Someone who has more experience may be answer your question more directly but I think the best answer will depend on what your datalogs show. Ever setup is different. Cams do move powerbands right but it is really more affected by the turbo you are running. In my experience on my 1JZ going from stock to 272s on the same 60-1 turbo, that "island" you refer to didn't actually move at all. I just had less drop off of that island when approaching redline. If anything, island actually started slightly earlier.
Timing? Just add a degree and log a run. If your knock counts go above 3 back off. Rinse and repeat.
Thread
Thread Starter
Forum
Replies
Last Post
stockhatch
Performance & Maintenance
4
10-20-10 06:21 AM