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View Full Version : Cruising 70mph+ AFR/EGT questions
modaddict 12-18-2007, 05:02 PM Some of you may know the path I've taken and the different turbo kits and tuners I've had on this car. It's pretty cool to see the differences in how people tune.
I have 5 gauges including a WB02 and EGT, and after I-speed and I were doing the EasyECU tuning via the internet, my "cruising" mileage went down from my last tuner, PDX. I could consistantly hit 27mpg before, now only 24.
(I switched from a perrin 30r kit, to a Crawford 35r kit)
One thing I specifically asked PDX to do, was to get me some increased mileage. AT that time, I didn't have the EGT/WB02 working.
I did not tell I-speed to work on my mileage. So, I wanted it back. I asked bill to send me a map that would put me in the 15:1 range for cruising.
Basically, I was running at 14.3-14.7 range with a EGT of ~1425-1450
Now, at 14.9-15.5 I'm at 1475-1500 EGT*
My question is that, will an 1100 mile trip, have any negative effects running at 1500*?
Honda is leaning out in the 20:1 range (College, I went to Ford's automotive program and my instructor told me this) untill they see the crankshaft start to vibrate from the Crank position sensor (misfires essentially). Why the hell can't we go in the 15's for AFR in our subaru's? the EGT on the honda's must be outragous. I can tell you, i've personally seen my old Civic header glow red after just cruising 75mph for 90 miles.
going from a mid 14afr to a low 15 afr made a huge difference in driveability. it surges slightly (mostly when cold) and doesn't feel as "torquey". I'm ok with it though.
Let me know your thoughts.....
Wheeler Bement 12-18-2007, 07:42 PM what are you cruising loads and rpms?
may just be a myth, but I'm staring to think that increasing the timing will lower the EGTs if you are at the point of not getting a complete burn...like still burning in the manifold the timing is so late. my car will run in low load(or cruise situations) on a wide range of timing values. the higher the timing value, the lower the EGT. I was getting 1450F just cruising 35mph in 3rd gear. the same was the case for other gears and faster speeds. I didn't like it, so I bumped the timing up and now it is more like 1250-1350. it feels better too. there is no way to really "quantify" any power numbers in this load range, so you have to go on feel and other things. I plan on taking it up even more to see what happens.
of course, my car is not even close to yours...but I'm willing to bet that your cruising loads are the same as mine, or close to it.
Freon 12-18-2007, 08:08 PM I think unless you have a very strict test regiment you'll have a hard time successfully impacting mpg with small tweaks. Don't expect to try a few things and see some obvious huge improvement pop out of the noise of your tests unless they're very carefully controlled. Manufacturers spend a lot of time and effort with much better equipment to wring a few extra points out of their cars. Anecdotal evidence abounds.
EliteTuning 12-18-2007, 09:38 PM i tune k20 hondas for 15.2-15.7 for more mpg as well
crazymikie 12-18-2007, 10:11 PM what are you cruising loads and rpms?
may just be a myth, but I'm staring to think that increasing the timing will lower the EGTs if you are at the point of not getting a complete burn...
it's not a myth at all. you are 100% correct. if you retard timing excessively, you will effectively end up with antilag and you will have fire going through your turbo. your turbo will not appreciate this, though ;)
as far as EGTs go, peak EGTs will always be highest around stoich. as you move richer OR leaner from stoich, EGTs will drop.
there are no generalizations for tuning a car- you have to understand what is happening to the motor and understand what is coming out of the motor to understand what adjustments need to be made.
mike
crazymikie 12-18-2007, 10:15 PM you probably need to adjust the timing in the cruise area now- leaner than stoich afrs will have a slower flame propagation which requires more timing advance to get a complete burn. that's probably the cause of your higher egts and the loss of torque.
i'm personally running in the 15.5:1 range now. it's hard to get good data, though since i have a short commute to work and the holiday traffic is causing the 3 miles to take 30-45 mins. the price you pay for living near a mall. i'm lucky if i get into second gear some days :(
i've added 1.5 degrees to my idle and cruise areas and my egts are back to where they were when i was running 14.7:1.
mike
Some of you may know the path I've taken and the different turbo kits and tuners I've had on this car. It's pretty cool to see the differences in how people tune.
I have 5 gauges including a WB02 and EGT, and after I-speed and I were doing the EasyECU tuning via the internet, my "cruising" mileage went down from my last tuner, PDX. I could consistantly hit 27mpg before, now only 24.
(I switched from a perrin 30r kit, to a Crawford 35r kit)
One thing I specifically asked PDX to do, was to get me some increased mileage. AT that time, I didn't have the EGT/WB02 working.
I did not tell I-speed to work on my mileage. So, I wanted it back. I asked bill to send me a map that would put me in the 15:1 range for cruising.
Basically, I was running at 14.3-14.7 range with a EGT of ~1425-1450
Now, at 14.9-15.5 I'm at 1475-1500 EGT*
My question is that, will an 1100 mile trip, have any negative effects running at 1500*?
Honda is leaning out in the 20:1 range (College, I went to Ford's automotive program and my instructor told me this) untill they see the crankshaft start to vibrate from the Crank position sensor (misfires essentially). Why the hell can't we go in the 15's for AFR in our subaru's? the EGT on the honda's must be outragous. I can tell you, i've personally seen my old Civic header glow red after just cruising 75mph for 90 miles.
going from a mid 14afr to a low 15 afr made a huge difference in driveability. it surges slightly (mostly when cold) and doesn't feel as "torquey". I'm ok with it though.
Let me know your thoughts.....
modaddict 12-19-2007, 06:28 AM what are you cruising loads and rpms?
I was getting 1450F just cruising 35mph in 3rd gear. the same was the case for other gears and faster speeds. I didn't like it, so I bumped the timing up and now it is more like 1250-1350. it feels better too. there is no way to really "quantify" any power numbers in this load range, so you have to go on feel and other things. I plan on taking it up even more to see what happens.
at 70mph, my cruise load is about .81-.84 and rpms are 2850's-2860's.
Remember also, we *might* have egt probes in different locations. Mine is in the stock header at the "button" on the drivers side...about 2-3" from the head.
you probably need to adjust the timing in the cruise area now- leaner than stoich afrs will have a slower flame propagation which requires more timing advance to get a complete burn. that's probably the cause of your higher egts and the loss of torque.
i'm personally running in the 15.5:1 range now. it's hard to get good data, though since i have a short commute to work and the holiday traffic is causing the 3 miles to take 30-45 mins.
i've added 1.5 degrees to my idle and cruise areas and my egts are back to where they were when i was running 14.7:1.
mike
good reply mike. i totally understand that.
How much timing are the guys with the ej257's running at low loads, cruising the highway? This is going to be a kicker to see the differences from car to car.
thanks guys..
modaddict 12-19-2007, 06:39 AM How much timing are the guys with the ej257's running at low loads, cruising the highway? This is going to be a kicker to see the differences from car to car.
dynamix 12-19-2007, 06:42 AM about 39 degrees at 0.75 load (typical cruise load)
modaddict 12-19-2007, 06:51 AM about 39 degrees at 0.75 load (typical cruise load)
thanks for the reply!
I'm about 41* at that load.
Anyone else?
Jon [in CT] 12-19-2007, 05:02 PM How did an EcuTeK EasyECU tuning thread end up in the Open Source Reflashes forum?
modaddict 12-19-2007, 05:15 PM ;20450906']How did an EcuTeK EasyECU tuning thread end up in the Open Source Reflashes forum?
:rolleyes:
Because more people in Open source know their own values vs. Ecutek
Because people with Ecutek tend to "set it and forget it"
Because I have several friends with Open source.
Because this forum, albeit new, should have more viewers than the Ecutek forum.
I'm sure as $^#% Glad I had to explain myself to you.
:rolleyes:
Does it really matter as I am asking Values and not Open Source specific questions?
:)
Wheeler Bement 12-19-2007, 09:58 PM at 70mph, my cruise load is about .81-.84 and rpms are 2850's-2860's.
Remember also, we *might* have egt probes in different locations. Mine is in the stock header at the "button" on the drivers side...about 2-3" from the head.
my EGT is in the same spot as yours.
I have a 2.0, and am running about 38 in that load spot, target AFR at 15.04. I did not realize you had an STI...but still.
I believe that is close to stock as well. I have not really tweaked this spot yet. I'm sure there is room for more.
Phatron 12-20-2007, 02:07 AM i hate ecutek. had it put on my 06 over a year ago and now i cant get rid of it to put enginuity on it.
modaddict 12-20-2007, 06:04 AM i hate ecutek. had it put on my 06 over a year ago and now i cant get rid of it to put enginuity on it.
Do you have to buy a whole new ECU?
sense of nature 12-21-2007, 12:18 AM Do you have to buy a whole new ECU?
Or get a licensed Ecutek shop to reflash back to stock
Kastley85891 12-22-2007, 05:58 PM Or get a licensed Ecutek shop to reflash back to stock
I to was flashed with ECUTEK - I sent my ECU back to tuner for base flash - bought an AP - now going to open source.
renhoek 12-27-2007, 12:33 AM thanks for the reply!
I'm about 41* at that load.
Anyone else?
FWIW, I run 42.5 at that load/rpm at 16.2 AFR.;) EGT is 1400 at the button.
cheers
modaddict 12-27-2007, 11:38 AM small update:
i drove from San Clemente, Ca to home in Wa state....about 1250 miles.
I averaged 82mph through Cali with the stops for gas/food and such (on the road, it was higher ;)
The car ran at 15.0 AFR with 1450 EGT. Just for giggles, I added torco all the way through cali and stopped when I was able to get 92 in oregon and washington.
no tickets. Seen a car ENGULFED in flames...that was pretty cool. Firetrucks hadn't gotten there yet.
Only 2 streetraces :rolleyes: 2 sti's tried to pick on the wrong silver sti. water/meth FTW!
I averaged about 22mpg at 85-90mph. If I slowed down to the low 70's, I was getting 25+
*shrug*
Zumble 12-27-2007, 11:53 AM Two STIs tried to pick on you and you say water/meth for the win? How about that GT35R you have in there? =P I'm pretty sure they weren't packing like you were.
Ever since I installed my perrin headers/FMIC and moved my probe to the cylinder 4 collector my EGTs have been around 1200F while cruising and barely breaks 1400F when in boost. I'm still working on tuning my car so full boost for me is only ~16psi on my 20G. WOT EGTs will probably go up as I turn up the boost.
One word on torco. It really Fs up your exhaust/combustion components. It gave a nice bright orange coating to all my spark plugs and the turbine of my old turbo. Yes it works! But, I don't know what bad things (if any) the orange coating does.
small update:
i drove from San Clemente, Ca to home in Wa state....about 1250 miles.
I averaged 82mph through Cali with the stops for gas/food and such (on the road, it was higher ;)
The car ran at 15.0 AFR with 1450 EGT. Just for giggles, I added torco all the way through cali and stopped when I was able to get 92 in oregon and washington.
no tickets. Seen a car ENGULFED in flames...that was pretty cool. Firetrucks hadn't gotten there yet.
Only 2 streetraces :rolleyes: 2 sti's tried to pick on the wrong silver sti. water/meth FTW!
I averaged about 22mpg at 85-90mph. If I slowed down to the low 70's, I was getting 25+
*shrug*
modaddict 12-27-2007, 12:19 PM Two STIs tried to pick on you and you say water/meth for the win? How about that GT35R you have in there? =P I'm pretty sure they weren't packing like you were.
Ever since I installed my perrin headers/FMIC and moved my probe to the cylinder 4 collector my EGTs have been around 1200F while cruising and barely breaks 1400F when in boost. I'm still working on tuning my car so full boost for me is only ~16psi on my 20G. WOT EGTs will probably go up as I turn up the boost.
One word on torco. It really Fs up your exhaust/combustion components. It gave a nice bright orange coating to all my spark plugs and the turbine of my old turbo. Yes it works! But, I don't know what bad things (if any) the orange coating does.
I should have said cp35r + water/meth FTW :)
:lol:
I gotcha on torco. My tip turned orange...and I laughed. I'm more worried about the o2 sensors than anything. I only used 2 cans. And not a full can at a time....about 3/4 of a can at a time for a full tank.
Zumble 12-27-2007, 12:30 PM I never saw any orange residue on my WB02 which is mounted about 12" away from the turbo (TXS Downpipe). My turbine blades, turbine housing, and wastegate flapper were covered in orange film though.
I should have said cp35r + water/meth FTW :)
:lol:
I gotcha on torco. My tip turned orange...and I laughed. I'm more worried about the o2 sensors than anything. I only used 2 cans. And not a full can at a time....about 3/4 of a can at a time for a full tank.
Kastley85891 12-27-2007, 12:40 PM I run TORCO every tank here in UT on teh crappy 91 - when I removed my VF39 it was bake din that orange **** - teh exhaust is brownie too ha ha -- no issues though and def runs better with it
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