not a whole lot of people offering feedback on this application like you guys are. you are a gift to the forum. Thank you.
not a whole lot of people offering feedback on this application like you guys are. you are a gift to the forum. Thank you.
2000 Ford Mustang - Top Sportsman
Thanks.
I only take credit for bringing this team together and bragging about their accomplishments.
I have a 2 year automotive degree from 2004, but can't say it's helped me much with this project.
i worked in dealerships for 8 years. nothing related to what i found here. im sure your learning and that's what counts most.
2000 Ford Mustang - Top Sportsman
We're not ready for release until at least cam timing is done (worst case when tune is done). Laz is having too much fun tweaking it. Since he's getting about 50 mpg highway with E10, it'll be worth the wait.
Looks like Laz is king and cam is his bitch.
Last edited by TownDrunk; 03-25-2017 at 09:44 AM.
Our latest tune is using cam timing from a 1.4l turbo Malibu + Laz's Lean Cruise changes, with some mild cam changes and everything else stock. Yesterday Laz averaged 50 mpg with 93 octane premium and no hypermiling techniques. I can't wait until our optimized VE and fueling changes are incorporated. Previously that was good for at least 2 mpg as well.
Since the best mileage occurs at the highest speed possible with the lowest rpm and minimum idle for the first gen Volt is 1400 rpm, our goal was to spend as much time as possible between 1400 and 1600 rpm at speeds of 60 mph and below. Last weeks version spent the most time at 1800 rpm (1600 rpm second) and I managed about 5 minutes with 45 mpg at 55 mph with E45 at 1600 rpm, but it was apparent there was room for improvement (like maintaining 1600 rpm at 60 mph). Today's version tweaks the leanness and timing to give more torque at 1400-1800 to quickly get to a low rpm and stay there.
Our latest version has been doing great at staying at 1600 rpm (beating out 1800 for highest count) and Laz is still dialing in the best lean cruise AFR. We may be reaching diminishing returns, as it's getting harder to get a mileage increase. Although this tune is great without lean cruise, LC itself is good for 10, maybe 15% better mileage.
Laz just discovered we have electric thermostats in the latest version of HPT, which may fix his complaint of coolant temps falling too low when the fans kick in and his mileage drops (like I've had that problem in ND). So we went to System... Fans... and bumped "Desired ECT" from 176 to 194 deg F.
Last edited by TownDrunk; 05-01-2017 at 07:04 PM.
We are finally moving out of alpha into beta status. Laz has started prep for adding ethanol changes and adding some spark timing. Cam and lean cruise changes have been put on hold for now.
Laz also has an interesting theory that throttle position is related to engine revving and hybrid engine shut-off and we are currently testing those changes. He thinks that data is hard-coded in a table we're not able to see from HPT. When's the last time you had anyone address that in a tune?
just picked up a 14 and might start playing with stuff. is there another place you guys are having this discussion? I'd like to follow alongOriginally Posted by TownDrunk
I have a 2nd Gen Volt, but am having trouble getting HPT to read it. I'll try to get one soon though.
Very cool work you're doing BTW!
We currently have an active team of two so generally use email. What are you looking for in a tune? Is flex-fuel a consideration?
We hit a roadblock recently so will need to regroup so don't expect any flashable updates for a couple months. The Volt is such a different beast that it's been a challenge. There's no other application like it anywhere.
Hi Giambals. That would be very cool! Email [email protected] and they can help you. I'm doing the same thing with my wife's new Buick.
Thanks.
PM me your email address. I have the file from my 2017 Volt.
PM sent. Thanks!
Giambals, if KSef can read his ECM, but you can't, possibly you have a different ECM firmware version. I ran into that when I had to replace mine and had to work with support to get the latest one to work.
We dropped the Silverado-based tune since starting with stock Volt was working better. Lots of timing and cam advance was added and today we're just finishing up cam and timing and switching to E85.
Also today added part of Jeremy's VE changes.
Since we have a lot more timing than stock it won't take much to be ready for E85. I suspect we'll be mostly done with this in a few weeks.
We've dropped the stock tune in favor of the '17 Buick Encore 1.4l turbo. We found it was similar to what we already had in the stock tune and it did it a bit better. We blatantly stole fuel, spark, cam, & fans. It even had good support for ethanol so we stole that too.
Initial tests showed retarding exhaust cam for 1400 to 1800 by 3 degrees and advancing intake cam for 1800 and above by 3 degrees, was a good start.
Mileage on the previous (stock-based) tune was only 17% below mileage on premium fuel, which we thought was pretty good.
Last edited by TownDrunk; 07-20-2017 at 07:57 PM.
Was the 17% below Premium on e85?
What highway MPGs do you have the car up to with the new tune?
Yes. We've been using premium for initial tuning lately. I used to use E30. Using premium means less time spent removing timing, only having to add it back later.
Yesterday was a calm day and I had a 41.3 and 43.3 mpg at 70 and thought it needed more work at 2000 rpm and below. I'm working primarily with cam timing.
We've already seen close to 45 (real world) mpg. Just need to make that happen more often. I'm hoping tweaking cam for 2000 and under will achieve that.
Last edited by TownDrunk; 07-24-2017 at 08:18 PM.
I'm seeing 43 mpg at 70 mph with latest cam changes. We'll see after Laz is done with VE changes (from Encore this time instead of stock Volt). With such dramatic cam changes, it's waay off now.
Last edited by TownDrunk; 07-30-2017 at 09:57 AM.
Our latest cam tune for the cruising range, .24 to .36 cyl airmass, (again based on 2017 4 cyl turbo Buick Encore) is:
- Exhaust cam for 1200 rpm to 1800 rpm retarded up to 3?, then subtract the same amount of exhaust retard from intake (to maintain stock overlap), then advance intake another 2?. I say "retard up to" 3? because you can't go lower than zero, so much of exhaust cam was .25 and for cruise rpm/load it ended up about 1-2?. Since the Volt idles at 1400 rpm, the change at 1200 rpm is more smoothing. I was amazed that just retarding exhaust a degree or two in this area was good for 3 mpg (but again, we needed more overlap).
- Intake cam advanced 3?, exhaust cam advanced 3? for 2200 to 3000. We originally had just intake advanced 3?, but this narrowly beat out just intake for mileage. Since any time spent above 2200 rpm isn't good for mileage, the biggest gains were from 1600 to 2200.
- 2000 rpm is smoothed horizontally for intake and exhaust.
- intake/exhaust is blended above and below changes.
We added HO spark to maintain about 3? of KR and are using the Encore's stock knock settings.
We thought the stock Encore tune was pretty good, but because there's no low load on our Volts, had to beef up the low rpm side with a that 2? of overlap to make a bit more power.
One of the tools we're using for cam timing is my mpg pid in a graph. I have two graphs, one with cylinder air mass on the left and another with vehicle speed. That gives me an average mpg for each rpm/load or rpm/speed. I usually use the rpm/speed graph the most. Then based on the amount of time spent at a certain rpm (count) and the mileage at that rpm, I can evaluate the cam timing at that spot. If one tune gives me a higher count at say 1600 rpm and the same (or better) mileage, I'll use the 1600 rpm cam for that tune.
Our latest cam tune for the cruising range, .24 to .36 cyl airmass, (again based on 2017 4 cyl turbo Buick Encore) is:
- Exhaust cam for 1200 rpm to 1800 rpm retarded up to 3?, then subtract the same amount of exhaust retard from intake (to maintain stock overlap), then advance intake another 2?. I say "retard up to" 3? because you can't go lower than zero, so much of exhaust cam was .25 and for cruise rpm/load it ended up about 1-2?. Since the Volt idles at 1400 rpm, the change at 1200 rpm is more smoothing. I was amazed that just retarding exhaust a degree or two in this area was good for 3 mpg (but again, we needed more overlap).
- Intake cam advanced 3?, exhaust cam advanced 3? for 2200 to 3000. We originally had just intake advanced 3?, but this narrowly beat out just intake for mileage. Since any time spent above 2200 rpm isn't good for mileage, the biggest gains were from 1600 to 2200.
- 2000 rpm is smoothed horizontally for intake and exhaust.
- intake/exhaust is blended above and below changes.
We added HO spark to maintain about 3? of KR and are using the Encore's stock knock settings.
We thought the stock Encore tune was pretty good, but because there's no low load on our Volts, had to beef up the low rpm side with a that 2? of overlap to make a bit more power.
One of the tools we're using for cam timing is my mpg pid in a graph. I have two graphs, one with cylinder air mass on the left and another with vehicle speed. That gives me an average mpg for each rpm/load or rpm/speed. I usually use the rpm/speed graph the most. Then based on the amount of time spent at a certain rpm (count) and the mileage at that rpm, I can evaluate the cam timing at that spot. If one tune gives me a higher count at say 1600 rpm and the same (or better) mileage, I'll use the 1600 rpm cam for that tune.
First, great work on tuning the Volt, this thread is amazing. I've been too afraid to touch my Volt tuning-wise, all my experience is on the L36, which is a dinosaur compared to this thing.
@TownDrunk, is the attached tune file at the top of the thread the latest and greatest? I have a 2012 Volt that I put 45 gas miles on a day. Any mileage improvement would be great. Also, I live in the Hell's incinerator heat-wise, July in Phoenix, so mileage here in the summer is extra special bad.
2003 Chevrolet Monte Carlo SS
(custom cam, L67 SC swap, fenderwell intake, headers, 42lb injectors, ported throttle body, on and on)2012 Chevrolet Volt (stock, 75k miles, 170+ lifetime mpg)
2015 Chevrolet Traverse LT (wife's people-mover)
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