AEM EMS and Vortech Supercharger with smaller pulley update
06-04-2003, 06:42 AM
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Just an update for those interested. Some quick background info:
AEM EMS running v.94
2002 S2000 with lots of mods, most importantly Vortech Supercharger with smaller pulley(s), and 755cc injectors from Ultimate Racing.(I no longer run the Vortech map signal voltage clamp, FMU or timing black box. Running on stock fuel pressure.)
A really good AEM EMS tuner(in fact the only one I know of in New England)
Have the car pretty much dialed in with the 4.5" pulley.(stock is 5") Very streetable, just like a stock Vortech kit with more hp and more boost down low. I have 1psi around 4000rpm. The pulley isn't producing as much boost as I thought it would(only ~9psi) so this weekend a 4.25" pulley is going on. Should get me around 11psi.
VTEC engages only when I go above 0 psi and the rpms are above 4500. This results in excellent fuel economy! We are using two fuel tables, one for each cam. The base fuel table in the EMS is for the little cam and the nitrous table is triggered with VTEC and runs as long as VTEC is engaged.
Right now I'm in the 12:1 fuel range when I am in boost. The timing is still heavily retarded for safety. After I get the 4.25" and do a rough tune I am hoping to get to the dyno to tweak the air/fuel and timing, find the correct vtec engagement point and to get a nice big hp number.
Problems I've had with AEM EMS:
Coolant idiot gauge does not work. (This fix is coming in v1.00)
Vehicle Speed Sensor(VSS) bug. This was a BIG problem. We wasted hours trying to figure out what was going on. Long story short, my fuel pump was cutting out randomly and we didn't know why. My speedo was working fine, but I guess because of my yellowbox(for my 4.44 gears) the internal speed sensor of the EMS was freaking out and registering over 130mph(sometimes 200+). Well the normal "bug" that most people see is that if they run on the street/track or dyno over 125mph the fuel pump shuts off much like a factory speed limiter. Only problem for me was that because of the yellowbox(I think) the EMS was seeing speeds over 125mph when I was really doing 35mph! Needless to say I went crazy trying to figure it out. In the end I changed a setting in the VSS setup menu per AEM tech support and this turned off the VSS sensor in the EMS(but not for my car) so all is well for now. v1.00 will fix this also.
Praise I have for the AEM EMS:
It is THE best ECU out there for any car(provided you have a tuner or the ability and time to tune it).
The tech support is awesome.
It has more power and features than most can take advantage of, but they are there if you need them.
In the right hands it makes BIG POWER!
AEM EMS running v.94
2002 S2000 with lots of mods, most importantly Vortech Supercharger with smaller pulley(s), and 755cc injectors from Ultimate Racing.(I no longer run the Vortech map signal voltage clamp, FMU or timing black box. Running on stock fuel pressure.)
A really good AEM EMS tuner(in fact the only one I know of in New England)
Have the car pretty much dialed in with the 4.5" pulley.(stock is 5") Very streetable, just like a stock Vortech kit with more hp and more boost down low. I have 1psi around 4000rpm. The pulley isn't producing as much boost as I thought it would(only ~9psi) so this weekend a 4.25" pulley is going on. Should get me around 11psi.
VTEC engages only when I go above 0 psi and the rpms are above 4500. This results in excellent fuel economy! We are using two fuel tables, one for each cam. The base fuel table in the EMS is for the little cam and the nitrous table is triggered with VTEC and runs as long as VTEC is engaged.
Right now I'm in the 12:1 fuel range when I am in boost. The timing is still heavily retarded for safety. After I get the 4.25" and do a rough tune I am hoping to get to the dyno to tweak the air/fuel and timing, find the correct vtec engagement point and to get a nice big hp number.
Problems I've had with AEM EMS:
Coolant idiot gauge does not work. (This fix is coming in v1.00)
Vehicle Speed Sensor(VSS) bug. This was a BIG problem. We wasted hours trying to figure out what was going on. Long story short, my fuel pump was cutting out randomly and we didn't know why. My speedo was working fine, but I guess because of my yellowbox(for my 4.44 gears) the internal speed sensor of the EMS was freaking out and registering over 130mph(sometimes 200+). Well the normal "bug" that most people see is that if they run on the street/track or dyno over 125mph the fuel pump shuts off much like a factory speed limiter. Only problem for me was that because of the yellowbox(I think) the EMS was seeing speeds over 125mph when I was really doing 35mph! Needless to say I went crazy trying to figure it out. In the end I changed a setting in the VSS setup menu per AEM tech support and this turned off the VSS sensor in the EMS(but not for my car) so all is well for now. v1.00 will fix this also.
Praise I have for the AEM EMS:
It is THE best ECU out there for any car(provided you have a tuner or the ability and time to tune it).
The tech support is awesome.
It has more power and features than most can take advantage of, but they are there if you need them.
In the right hands it makes BIG POWER!
06-04-2003, 07:08 AM
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Stock internals? Toda (or other) cams?
I just bought a set of the new Todas and a Vortech SC. Hopefully, they will complement eachother. Also hoping that the bored-out TB will now make a difference. It adds nothing to a stock engine (at least for my car).
I just bought a set of the new Todas and a Vortech SC. Hopefully, they will complement eachother. Also hoping that the bored-out TB will now make a difference. It adds nothing to a stock engine (at least for my car).
06-04-2003, 07:11 AM
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Stock internals, stock cams. I do have a proflow throttle body. See my sig for mod list.
Cams won't return their cost in parts and labor with the supercharger, the difference will be minimal. Spend the same money on an AEM EMS, smaller pulley and big injectors and and you will add much more power than the cams.
Cams won't return their cost in parts and labor with the supercharger, the difference will be minimal. Spend the same money on an AEM EMS, smaller pulley and big injectors and and you will add much more power than the cams.
06-04-2003, 08:05 AM
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JENNER, 1st your the man! 2nd I have a comptech kit and wanted to know how small of a pulley I can run with out changing injectors and computer, with out having a intercooler. But it must be safe for my motor. So what do you think? Thanks
RAT
RAT
06-04-2003, 09:28 AM
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I don't have a comptech kit or any knowledge of pulley sizes for that kit(Comptech uses different sizes than Vortech).
I would say that without changing injectors, intercooler and computer I wouldn't upgrade it all at because more boost without those three items won't be very safe.
I would say that without changing injectors, intercooler and computer I wouldn't upgrade it all at because more boost without those three items won't be very safe.
06-04-2003, 11:51 AM
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I can't believe you're wanting to run about .75 bar on an 11:1 compression engine!! I guess as long as it is tuned correctly (fuel, timing, etc) there isn't anything actually wrong with it, it just seems to fly in the face of conventional wisdom.
Good luck with tuning, may you have many trouble free miles!
Good luck with tuning, may you have many trouble free miles!
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06-04-2003, 12:25 PM
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With those large injectors, are you have trouble starting and ideling your car? How does it run with the 755's? Do you think they are to large? I am turbo and gettign bigger injectors and am thinking of only 550's. I might get larger ones if they can be tuned pretty good with the EMS.
Kevin
Kevin
06-04-2003, 12:29 PM
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It runs/idles perfect. Like it was stock(well a little louder and a lot faster than stock 
).
You have to tune everything from the ground up with the AEM EMS. Thus I can set the car to idle exactly how it should. The same with different pressure numbers, at different rpms on different cams. It is a completly custom/unique tune for my exact setup. Nothing else out there can come close!
).You have to tune everything from the ground up with the AEM EMS. Thus I can set the car to idle exactly how it should. The same with different pressure numbers, at different rpms on different cams. It is a completly custom/unique tune for my exact setup. Nothing else out there can come close!
