I had Michelin Premier A/S tires on the 2002 Volvo S40 I just traded as part of the Volt deal. Very quiet and confidence-inspiring tire. Did you notice a mileage hit over the stock rubber? I had heard the Michelin Energy Saver A/S was best for mileage but scary in the wet. Sorry, don't mean to highjack this thread.
Ray
I lost about 3 miles of EV with my 235-50/17’s, that I never got back, but great with wet roads and not bad with snow either. I try to keep them about 40 psi.
Yes, I've always been a fan of slightly high pressure in tires. Will review the threads on GM-Volt as you suggest.Originally Posted by TownDrunk
Meanwhile, back in tune town, how is that project progressing? Are you and the other mad scientists a month or two away yet from releasing it?
Ray
Our first lean cruise test was last night. Lean cruise just affects 2000 rpm and below, so for most Volt driving that would be 1400 to 2000 rpm.
Before the test, I had a 10 mph tailwind and spent 2/3 of the time at 1600 rpm, which is fantastic.
Mileage with lean cruise at 1600 rpm went from 43 mpg to 49. 1800 rpm (which we don't hit much) went from 41 mpg to 47 mpg and 2000 rpm from 38 mpg to 42. My test was with a headwind and most of the time at 75 mph (needed to get home) so not great overall mileage... 39 mpg.
Of course lean cruise means less power at that speed so there's often less hits at that speed so more tweaking will be needed. We're testing even leaner tonight.
I'd like to release our tune no later than the next month.
Sounds like you are getting more than your share of data points. Very complicated process. This is definitely NOT a "one and done" activity
Ray
We're definately weeks away from a release.
Ray, I sent you a PM.
Hi Guys,
I bought my tuner just from reading this thread. Looking forward to the tune. In the meantime, I hope to figure out how to merge the two files.
Hi Mick,
The first tune is obsolete and won't get you what you want. You could merge the driver demand tables to get you a more sport-like accelerator pedal.
What year Volt do you have and what part of the country do you live? I'm especially interested in anyone living in a high altitude, since that's untested.
I just bought a volt due to this thread. I hope to be able to contribute.
Welcome aboard! I just bought mine last Sunday. Still getting used to the silence and the passing of gas stations!
Ray
Hi Mac,
More info please? What year Volt?
Any special skills you have? Our biggest contribution would be to have a second gen user join (or get our hands on one).
Tuning is just about done. We need a couple weeks to refine lean cruise (~16.5 AFR for 2000 rpm and below). After that it'll just be tweaking, but I suspect tweaking will go for quite some time.
Last edited by TownDrunk; 10-07-2017 at 01:48 PM.
Mine is a 2015. I'm near Chicago, so no extreme altitude for me.
I don't think the obsolete tune is in the repository so I can't use it anyway. I am going to try a tune on my father in laws 2012 Silverado to see how it works while I wait for the Volt tune.
I suspect you will find 15.5:1 AFR which corresponds to peak EGT gives you the best economy on a generator
(Since it runs near wot at varying RPM)
This is what airplanes do for economy.
16.5 is great at demanded loads below what WOT at 1200 will provide. But should be less efficient on most motors than peak EGT at higher loads.
Has anyone pyro'd the Volt motor?
Laz and I already had that discussion (about 15.5 AFR). He's researched it a LOT and has implemented lean burn several times:
Assuming stoich is 14.7:1, as in 0% ethanol, as every graph or table pre-2010....
15.4:1 produces the most torque. This was the point where carburetors could be tuned to in order to produce the most fuel economy. Going leaner than 15.4 wasn't really an option with these engines and carburetors, with the exception of DFCO.
16.2:1 produces the most fuel economy without a stratified charge or combustion premix of some type. It's the AFR Holden aimed for at cruise RPM and load for it's fuel injected v8 engines in the 2000s.
Holden also would go a bit leaner as RPM and load requirements went down as lean as 17:1, typically where coasting or very slight decerarion were happening.
Honda went as low as 22:1 with their lean burn technology, producing the still unmatched first gen Honda insight.
Lastly, cars since the seventies and into today all go as lean as infinity:1, also known as deceleration fuel cut-off or DFCO, during (you guessed it) deceleration. There is a quick transition from 14.7:1 through increasing-numbers:1 and all the way to infinity:1 as the fuel is cut.
Here's more info...
https://en.wikipedia.org/wiki/Lean-burn
I'm not aware of anyone checking cylinder head temps.
Hi Mick,
The obsolete tune is in my first post. It has less optimal cam timing and too little spark timing. We've learned a lot since that was released.
I need to create a post with the required config files for logging and setting up VCM Scanner. We also need a good guide to install the ethanol sensor for those that want to create a FFV Volt.
I have a 2013 Volt and I'd be willing to try this at altitudes up to 9000 feet nearby if I can get the money together for a tuner.
Hi Mom,
Are you referring to buying Tuner ($500) or just get someone to flash it for you? Buying it yourself requires a laptop in the car and we'd be interested in a log while you're at altitude.
Do you have any tuning experience?
Any computer experience? Setting up scanner requires copying some xml files to your hard drive.
I don't have any tuning experience, but I am a certified computer tech and I do nearly all of my own repairs/maintenance on my vehicles. So it shouldn't be that big of a learning curve
I'm assuming that I'd have to have the tuner to test and log.
I'm going on a trip to northern NM and I could drive up into Colorado and possibly get so 10,000' or higher roads. But that's probably a week away.
Having a laptop with the software installed and set up is the hardest part. When I get a chance I'll post how to set up VCM Scanner for our Volt. Once you have the software, PM me.
It will probably be a month or two before I can purchase the software and such. If somebody can lend me the gear, I wouldn't mind doing the testing and then returning it to hurry this along.
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