Greetings from an old school shade-tree mechanic in the Green Mountains

[Lean Burn enthusiast]

Hello,

I've been a long-time reader of gassavers.org, and I'm happy to finally join in.

Back in the late '70s I worked my way through school as a mechanic, and was lucky enough to work for the owner of a shop who invested in a Sun 1115 engine analyzer complete with exhaust probe; with this we could troubleshoot our way through some counterintuitive driveability issues that other shops gave up on. During the early days of the crude, vacuum-controlled uncomputerized 1st generation emissions controls, by using this big monster we troubleshot to the faulty component instead of just shotgunning with new parts until the problem disappeared. It was a valuable lesson that I since used in both the computer and avionics disciplines.

I studied electronics, got a 1st-class radiotelephone license in order to work on large radio/TV transmitters...but ended up joining the computer industry as a systems support engineer. I also joined the Air Guard, and specialized in avionics (radar) for the C-130 & F-106 aircraft.

But even though I worked on computer systems at the day job & avionics on drill weekends, I continued to work on cars for fun. As for my interest in fuel economy, the year before I got my driver's license gas was being sold in the Midwest for roughly 35 cents/gallon. Right after the Arab oil embargo I got my license, and gas had jumped to 99.9 cents/gallon! Doesn't sound like much today, but at the time I was landscaping after school for $2/hour...after taxes, every hour I worked I could buy roughly 1.5 gallons of gas. To put this into perspective, it would be as if gas was currently $20/gallon! Needless to say, I read everything I could find on fuel economy, learned about spark timing curves, adjustable vacuum advance canisters, jetting, power valves, and what BSFC meant. Probably the single best book I read at the time was Doug Roe's book on Rochester carburetors, with the big Quadrajet on the front cover.

Prompted by the high cost of feeding American cars with 7-liter V8s, I switched to used European Fords -- first a 1600cc Capri, followed by a 2600cc Capri, and then I really hit my small car groove in the late '80s with a 10-year-old '78 Ford Fiesta with the 1600cc crossflow Kent. With the factory 2-throat downdraft weber carb, header, a 1" engine drop kit, rear 19mm sway bar & 13" euro-spec Ford steel wheels, all sourced from BAT...I discovered that you could have more fun at/near the speed limit in one of these street-legal go-karts than I did in the V8-powered muscle cars. Beating 30mpg out of a series of previously enjoyed 'one car payment' Fiestas while paying $1.29/gallon for gas meant that I was spending more on my coffee habit than my daily commute -- life was good, and my interest in max-economy cars languished.

****
Years pass, and as my last Fiesta rusted away I looked long & hard for the next platform to ride. I started by looking for a clean used CRX HF, but they were made of unobtanium. I then decided to look for what looked to be *the* Honda Fiesta -- the '89-'91 Civic hatchback. I found a rust-free '89 on eBay in Florida, brought it home, and enjoyed the sheer bang/buck nature of driving this around. By adding a hollow large-diameter front sway sourced from an Integra & a few other low-buck mods, this car was way more fun than something this cheap had any right to be.

...And then in the '06 timeframe gas first flirted with $4/gallon, I had twin daughters headed towards college, I had a long commute, and thanks to the family budget at the time gas felt like it cost $40/gallon. Feeling the kind of positive tension I hadn't felt since the Arab oil embargo, a few of us at work started scouring the fueleconomy.gov database to see if there was anything close to the CRX HF. This is when we discovered the lean burn Civic VX, and we bought every one we could find & drove them back to VT. (MA, Long Island, CT, DC, FL, & AZ) They usually pay for themselves by cost avoidance at the gas pump in 24-36 months. (Back when we were buying them for $3K and spending another $600 in timing belts, water pumps, etc.) Truly amazing machines - I felt like I was paying $2 gallon while everyone else around me was paying $4/gallon. Surprisingly, it felt just as good as when you won at the dragstrip. Go figure. :-)

As for the Insights, the older ones with high mileage (ie: with no battery warranty) are becoming affordable. For example, in the spring of '11 I bought a 309,000 mile '01 Insight for $2800, and drove it from Austin to Burlington, troubleshooting it along the way. It now has 333,000 miles on it, is still on the original clutch & brakes...but this winter I'm going to completely renew the engine, clutch, transaxle, brakes, suspension, & test/repair the battery pack. My goal next spring is to have a brand new 0-mile Insight drivetrain, brakes, & suspension expertly camouflaged by a 333K mile '01 shell with it's fair share of patina. As they used to say, "Looks Bad, Runs Good."


And those twin daughters? When they graduated on the Honor Roll from middle school, I challenged them that if they maintained their high grades through high school & college, I would buy them their first new (to them) car(s) to start their careers with. They called my bluff, saw how cool my Insight was...and they chose to get Insights as well. (Their cars have <1/2 the mileage mine has, I had to rebuilt the 5-speed transaxle in one of them, but unless someone tells me differently, I'm thinking that we are the only triple '00-'01 Insight family in New England. Obviously, I couldn't be prouder of them.

****

Apologies for the length, but I've been waiting a long time to go from reader to writer on a website where I've found so much helpful info on Honda's lean burn automobiles. Now that my daughters have graduated college, I look forward to documenting & sharing some of the projects we've got lined up to try to further improve the BSFC of the stock VX & Insight engines for anyone who's working on similar projects.

Cheers --

dave

[Lean Burn enthusiast]

FWIW, I see a lot of activity in here having to do with the electric side of the hybrid equation as well as lots of good info on hypermiling techniques. It will take awhile, but I hope to take some of the theories from the following individuals and wash them against the D15Z1 & 3-cylinder Insight engines:

* John Deakin -- recip aircraft 'Lean of Peak EGT' lean-burn guru
* Larry Widmar -- "The Old One", fast-burn/high swirl combustion chamber & Honda guru
* Engine Masters -- the creative thought shown by folks like Jon Kaase as they try to mitigate parasitic losses (like oil windage around the crank) in order to generate the most power on the dyno within the rules of the yearly competition.

Plus stuff that was in Doug Roe's, Bill Jenkins', Smokey Yunick's, & Dave Vizard's books.
Philosophically speaking, in the case of my Insight I'd like to try some blueprinting & tuning techniques to see if any measurable improvement can be made on the gas side of the hybrid equation. As for the VX technology, I have a low-mileage, rust-free '90 Civic hatchback that I want to update with a complete D15Z1/tranny/P07 ECU drivetrain. If you look at my Avatar picture, this is a photo of a D15Z1 cylinder head experiment where I ported the head in order to take the mass-produced casting and optimize it as the original designer intended it to work. This head is now in service on top of a fully rebuilt D15Z1, and the results are encouraging -- it's hard to stay in lean-burn mode in the hills of VT, but with this new engine I can drive at the posted speed limits and stay in lean-burn for a higher percentage of my commute. Don't get me wrong, as-built the Honda engines are little jewels that are pretty close to ideal (especially for a mass-produced powerplant) but there still is room for measurable improvement. At least that's what I'm going to try to achieve, document, and share. This is going to be a lot of fun!

[IndyFetch]

Cool Cool stuff. Welcome aboard. It sounds like you have a lot to offer the site. I look forward to reading more.

[Lean Burn enthusiast]

I've always appreciated the constructive vibe at this website -- feels like a collaborative effort where everyone is pulling together in the shared pursuit of knowledge/actionable info. The data/drama ratio here is exceptional.

****

To give you a rough idea of our willingness to employ whatever it takes to divide/conquer obstacles to success, here's a pointer to a short (unplanned, crude, test) video where we're observing the output of a truck knock sensor on a Tektronix o-scope while I'm tapping the Ford 5-liter roller cam block with a hammer in order to simulate detonation:
5.0 Mustang engine with a knock sensor - YouTube

So what does all this have to do with gassavers.org? Well, it all started innocently enough; an airman in our shop (with a flawless driving record) wanted to build a 500hp engine for his convertible Mustang. I told him that I was too old to build another low-tech, high HP automobile that becomes yet another garage queen because it burned through too much fuel for the owner to drive on a regular basis. After much discussion, I agreed to get involved in the project if he agreed to build a drivetrain that would deliver 500hp at the flywheel + 20 mpg while on the factory cruise control out on the Interstate.

To do this, we figured that we would need to build an engine with a wide powerband, and keep the cylinder pressures up for max efficiency throughout the range. So we went with a forged 331ci stroker kit w/Mahle pistons, used a set of aluminum AFR cylinder heads with 165cc intakes (ported to flow like 185s) and cammed the engine for a wide powerband for street rpm. To this basic setup we added a Procharger supercharger with a large intercooler, a Snow water/methanol injection system indexed off the Litening MAF, a ported GT-40 intake, 60-lb. injectors...and managed all this with the stock Ford EEC computer via an outboard twEECer setup.

In English, we built a zero-decked short block, using a high quench piston/head combo to give us the lowest possible octane appetite for the ~9.9:1 compression ratio. The engine would cheerfully handle 99% of the daily driving chores naturally aspirated, with the supercharger ready to provide a sparkling top-end finish for short bursts of exceptional power...much like the afterburner in a modern fighter aircraft. This allowed us to neatly sidestep all the thermal management headaches associated with making this kind of power continuously.
(read: the owner's pockets weren't deep enough to afford this kind of power with any kind of real duty cycle. :-)
The Snow water/methanol injection gave us the on-demand octane we would need while under boost, theoretically giving us a jump from 92 octane to 116 octane when set to showerhead.

Sooooo, as long as nothing in the water/methanol delivery system failed during boost operation, we were OK. But if we did suffer a failure, at 14 lbs. of boost the high-compression engine would be driven into hard detonation, with an excellent chance that the Ford 5.0 block would crack & fail between the cam & crank, sneezing the crankshaft onto the pavement. It was felt that this was a non-goal well worth avoiding, so we drilled & tapped the seasoned crate motor block to accept the Ford truck knock sensor, and via the twEEcer we gave integrated it into the tune as a failsafe, backing off the ignition timing at the first hint of any trouble in paradise.

Behind this engine there's a Viper-spec T-56 with overdrive 5th & 6th gears. (The 6th a deep 0.5:1 ratio.) The car started out with a set of 3.73:1 diff gears, but with the ample torque on hand we went back to 3:23 gearing, improving both behavior during acceleration as well as lower cruise rpm.

It took us <30 minutes to dial in the WOT air/fuel ratios...but we spent almost 3 days methodically working through the driveability issues until we had the spark tables & fuel curves dialed in to our satisfaction. By manipulating the parameter where the EEC transfers from closed-loop O2 operation to open-loop mode, we got the car to stay in closed-loop mode while driving up I-89 on the cruise control. It was a lot of work to fully sort out (primarily to the spark blowing out under boost, but feeling like we were fighting a fuel delivery issue) ...but after it was all said & done, we were able to exceed our goals for both full power operation & fuel economy during light cruise operation.

Can't wait to take what we've learned from the project above & apply it to a best-reasonable-effort on a D15Z1 engine...

[Lean Burn enthusiast]

Here's a pointer to the finished vehicle on the dyno:

94 Mustang GT on the Dyno - YouTube

We overshot the performance goal - we ended up with 555 rwhp. (~625 at the flywheel)
Note that the car was built/debugged in VT, and the owner subsequently drove it to AZ, where this dyno test was performed. The good news is that in 6th gear cruising at ~1700 rpm the car delivered a 22 mpg average for the entire trip. (!)

With properly dialed-in computer-controlled engine management, you really can have high performance & (relatively) good cruise economy in the same vehicle...you just can't have both simultaneously. :-)

[Lean Burn enthusiast]

And here is the software tuning hammer (twEECer on a laptop, plugged into the ECU service port) that we used to dial in the Ford factory EEC-IV computer from the requirements of a stock 215hp 5.0 pushrod engine to the supercharged replacement engine that was making just shy of 3x the output. Skip to 0:40 to see the twEECer screen output: 94 Mustang GT vert rebuild first run part 2 - YouTube

****

Please don't take the above as senseless chest-beating...I just want folks to know that we like the challenge of taking something undervalued to the next level of performance and/or efficiency. We were 100% pleased with how the twEECer allowed us to dial everything in. My question is, which tuning vendor in the Honda ecosystem offers similar capability with the dual-processor OBD-I ECU that's unique to the D15Z1/P07 calibration?

And is anyone tinkering with the OBD-II ECU managing the Insight?

I'm sure that all this sounds a bit goofy at first blush, but I would be willing to explore an intelligent low pressure turbo setup architected to work off the strengths of the existing D15Z1 design if we could realize a sufficient real-world improvement in fuel economy.

The bottom line is that high output cars can only be enjoyed for just a handful of seconds a day before you run the real risk of losing your license & end up waitin' for the bus all day...whereas really high FE can be enjoyed every single moment that you are traveling from Point A to Point B.

So, armed with this epiphany I'm cheerfully altering my trajectory through the car hobby. And if we can figure out a successful LPT upgrade to the D15Z1, maybe we can take what we learned there & apply it to the Insight as well? I already own both vehicles in question, my daughters are through college, and it's time I stop spending other people's money & start spending some of my own. :-)

For anyone still reading this, thanks for your time & attention to this matter.

dave

[theholycow]

Originally Posted by Lean Burn enthusiast

The bottom line is that high output cars can only be enjoyed for just a handful of seconds a day before you run the real risk of losing your license & end up waitin' for the bus all day...whereas really high FE can be enjoyed every single moment that you are traveling from Point A to Point B.

Well said. There will always be somebody out there faster, and you will never consistently use the maximum performance potential of your souped up car...but when it comes to saving fuel you can safely and legally keep raising the bar every day. It's less exciting but more satisfying.

I'm interested in your knock sensor sub-project. I don't have time this morning but I'll have to check out that video. I drive a 1980 Buick LeSabre with a 4.1 V6 (125hp, woohoo!) and a 5 speed manual.

I'm basically new at this kind of stuff; I've been enjoying the puzzle of troubleshooting other people's problems online since 2007 or so, and doing my own repairs since maybe 2009. In 2010 I put in that transmission and, despite being completely unqualified, underfunded, and underequipped for the job, it's served me well for 40,000 miles now.

With overdrive, no computer, and no slushy torque converter, I can get some knock at low-medium RPM/medium-heavy throttle. I've compromised on ignition timing and gone to 91+ octane to find a good balance, but I dream of electronic spark control. There was a rudimentary system on newer related engines (turbo 3.8) that I've considered using; the sensor should bolt on. I'm not so sure about the programming, my research indicated that it might require lab testing and serious programming/design to tune the computer to detect knock for any particular engine.

...ok, looking over my notes, I don't think that was the issue. I think it was merely budget. This page describes a complete system for the 4.1 in 1982.
http://webcache.googleusercontent.co...520CONTROL.doc

[Rusty94cx]

There is a guy on a Honda board that had a d15 Jdm 3 stage vtec motor that claimed 50-60 mpg and 250 hp using a small turbo and properly tuned.
http://ecomodder.com/forum/showthrea...rbo-11881.html

[Chabadnik]

Dear Enthusiasts!
Can anyone answer my simple question? To lower AFR, is it enough to remap the AFR table (and which one?) or it requires tampering with more than one table?
Thanks in the advance.
I really hope there is someone able to answer, because no forum so far include people that know anything about it.