Jestr Tuning signup thread Oct-Nov
Last time I drove to MMP I got 338 miles on a tank.
The close loop table is apparently in ECU flash, but mislabeled. The developers on here have preliminary verification from a few months ago that the offset for that table matches the ECU Flash table. Nobody ever finished testing to build a final definition for the table. But I am experimenting with this to correct a closed loop tip-in lean issue I have.
That said, I run the car in open loop, and have seen as much as a 15% increase in fuel milage over closed operation for some reason. My open loop table is very close in most conditions, but I would still think I should see the best milage in closed loop. Perhaps the AFR hunting is causing my 680's to waste fuel?? Silly....no explanation makes sense to me yet.
But either way I have never seen over 250 miles to a tank....granted I have yet to do a steady freeway cruise for the entire tank of gas.
That said, I run the car in open loop, and have seen as much as a 15% increase in fuel milage over closed operation for some reason. My open loop table is very close in most conditions, but I would still think I should see the best milage in closed loop. Perhaps the AFR hunting is causing my 680's to waste fuel?? Silly....no explanation makes sense to me yet.
But either way I have never seen over 250 miles to a tank....granted I have yet to do a steady freeway cruise for the entire tank of gas.
well the first thing about the tune is, when you are idling and cruising you are using closed loop operation in the ECU. you cannot tune this, the ECU simply always targets 14.7 A/F as long as you don't mash on the pedal and go into open loop operation.
if somehow jestr magically can modify the closed loop targets and makes it 17or greater a/f ratio, he would make a killing tuning everyones car without a cat. granted running lean isn't to good for your engine, you would get better gas mileage. the only other ways to improve mileage is to improve the Volumetric efficiency of the engine, something a tune cannot do. VE is simply a matter of how the engine is designed, cam specs, lift, overlap, porting, back pressure... that kind of stuff. last, driving habits are the easiest way to improve mileage. obviously not using the throttle as often will help. anytime you tip in, your going rich from 14.7 which means your using more fuel. certainly tuning the open loop tables can improve mileage. there is no doubt about that. the leaner you run it the better the mileage you'll get. but this is only going to apply for when you are accelerating rapidly and using those open loop tables.
i know it is possible to disable the front o2 sensor and run entirely on the open loop tables, but i can't see jestr doing that with a reflash. it would take a good amount of tuning to make sure the car doesn't run to lean and highway speeds/city speeds and idle. any ideas what jestr did? or did he simply tune your car and now you regularly get 320 miles on a tank.
if somehow jestr magically can modify the closed loop targets and makes it 17or greater a/f ratio, he would make a killing tuning everyones car without a cat. granted running lean isn't to good for your engine, you would get better gas mileage. the only other ways to improve mileage is to improve the Volumetric efficiency of the engine, something a tune cannot do. VE is simply a matter of how the engine is designed, cam specs, lift, overlap, porting, back pressure... that kind of stuff. last, driving habits are the easiest way to improve mileage. obviously not using the throttle as often will help. anytime you tip in, your going rich from 14.7 which means your using more fuel. certainly tuning the open loop tables can improve mileage. there is no doubt about that. the leaner you run it the better the mileage you'll get. but this is only going to apply for when you are accelerating rapidly and using those open loop tables.
i know it is possible to disable the front o2 sensor and run entirely on the open loop tables, but i can't see jestr doing that with a reflash. it would take a good amount of tuning to make sure the car doesn't run to lean and highway speeds/city speeds and idle. any ideas what jestr did? or did he simply tune your car and now you regularly get 320 miles on a tank.
how lean are you running your open loop tables ethan? that would explain the better mileage in open loop if you are purposely running leaner then stoic.
Kevins explaination of his mileage was great. 280-290 was the mileage he claimed with his older tune (most likely his dynoflash tune). which would imply that he has excellent self control and a very smooth driving style. since the dynoflash tunes are usually very rich, improved mileage is definately seen when in open loop, thus he gets better mileage with the jster tune then before.
his car has relatively the same VE as all ours, thus leaving only driving habbits to make a difference in mileage. sense i routinely get 260-280 a tank (20 miles one way to work, 12 of which is highway), and fill up with 12 gallons to full, i can see draining the tank to almost 14 gallons used, achieving another 50 miles, or the claimed 320 miles on a tank. i guess the best thing to do is to label mileage in MPG, not miles per tank... cause i've staved my motor before on low gas at the track... it scared the crap out of me. now i fill up shortly after the light comes on, or else drive really easy.
at motorsport ranch i get a whopping 5 MPG
thats right, less then 70 miles on a full tank of gas... that was with my old turbotrix tune before i started tuning myself though... interesting to see how i do now
Kevins explaination of his mileage was great. 280-290 was the mileage he claimed with his older tune (most likely his dynoflash tune). which would imply that he has excellent self control and a very smooth driving style. since the dynoflash tunes are usually very rich, improved mileage is definately seen when in open loop, thus he gets better mileage with the jster tune then before.
his car has relatively the same VE as all ours, thus leaving only driving habbits to make a difference in mileage. sense i routinely get 260-280 a tank (20 miles one way to work, 12 of which is highway), and fill up with 12 gallons to full, i can see draining the tank to almost 14 gallons used, achieving another 50 miles, or the claimed 320 miles on a tank. i guess the best thing to do is to label mileage in MPG, not miles per tank... cause i've staved my motor before on low gas at the track... it scared the crap out of me. now i fill up shortly after the light comes on, or else drive really easy.
at motorsport ranch i get a whopping 5 MPG
thats right, less then 70 miles on a full tank of gas... that was with my old turbotrix tune before i started tuning myself though... interesting to see how i do now
no you missunderstood. on my older tune with dynoflash, ALL highway miles, i got nothing but 21 mpg. I was getting around 220-230 when the light came on. with Jestr's ive gone as high as 295 before the orange light came on. that is not ALL highway miles though. I do live in the city after all. the 21mpg on dynoflashs tune was what i realized on a trip to dallas. i've never had an ALL highway tank on jestr's tune so far. but with mixed driving, i've seen 280-290 (including racing and pulls here and there) before the orange light comes on regularly. and then to add to going 50+ miles into the orange before i got scared and filled it up. Are there any negative effects to driving your car till it runs out of gas? If not, i'd be willing to do it just to prove it to you guys that i get over 320-330+ miles per tank.
That's the weird thing. Since my trims were so close, I am near dead on stoich just cruising around and sometimes bit richer. Usually a range of 13.7 - 15, with 14.5'ish most of the time. As I have time, I do tweak it a bit to get it closer, but there is nothing lean I see to explain better milage.
You may remember that I view the wideband output on the dash full time and it's right in my line of sight Perhaps I subconsciously use the go pedal less in open loop... 
You may remember that I view the wideband output on the dash full time and it's right in my line of sight
Perhaps I subconsciously use the go pedal less in open loop... how lean are you running your open loop tables ethan? that would explain the better mileage in open loop if you are purposely running leaner then stoic.
Kevins explaination of his mileage was great. 280-290 was the mileage he claimed with his older tune (most likely his dynoflash tune). which would imply that he has excellent self control and a very smooth driving style. since the dynoflash tunes are usually very rich, improved mileage is definately seen when in open loop, thus he gets better mileage with the jster tune then before.
his car has relatively the same VE as all ours, thus leaving only driving habbits to make a difference in mileage. sense i routinely get 260-280 a tank (20 miles one way to work, 12 of which is highway), and fill up with 12 gallons to full, i can see draining the tank to almost 14 gallons used, achieving another 50 miles, or the claimed 320 miles on a tank. i guess the best thing to do is to label mileage in MPG, not miles per tank... cause i've staved my motor before on low gas at the track... it scared the crap out of me. now i fill up shortly after the light comes on, or else drive really easy.
at motorsport ranch i get a whopping 5 MPG thats right, less then 70 miles on a full tank of gas... that was with my old turbotrix tune before i started tuning myself though... interesting to see how i do now
Kevins explaination of his mileage was great. 280-290 was the mileage he claimed with his older tune (most likely his dynoflash tune). which would imply that he has excellent self control and a very smooth driving style. since the dynoflash tunes are usually very rich, improved mileage is definately seen when in open loop, thus he gets better mileage with the jster tune then before.
his car has relatively the same VE as all ours, thus leaving only driving habbits to make a difference in mileage. sense i routinely get 260-280 a tank (20 miles one way to work, 12 of which is highway), and fill up with 12 gallons to full, i can see draining the tank to almost 14 gallons used, achieving another 50 miles, or the claimed 320 miles on a tank. i guess the best thing to do is to label mileage in MPG, not miles per tank... cause i've staved my motor before on low gas at the track... it scared the crap out of me. now i fill up shortly after the light comes on, or else drive really easy.
at motorsport ranch i get a whopping 5 MPG
thats right, less then 70 miles on a full tank of gas... that was with my old turbotrix tune before i started tuning myself though... interesting to see how i do now Last edited by ez; Aug 1, 2007 at 02:00 PM.
i'll be down for this also if its only a dyno tune. i have the money. i already have his email tune, i want a dyno tune. count me in if its on a dyno. now i need to figure out if i need some new parts.
bone
bone