Honda Insight w/Acura TSX engine - Ecomodding - Page 38 - Fuel Economy, Hypermiling, EcoModding News and Forum

MetroMPG · 07-23-2019, 03:57 PM

Very impressive!

On a scale of 1-10, how frustrating is that 6th gear issue? (The lost MPGs would be driving me nuts.)

Ecky · 07-23-2019, 04:03 PM

Quote:

Originally Posted by MetroMPG

Very impressive!

On a scale of 1-10, how frustrating is that 6th gear issue? (The lost MPGs would be driving me nuts.)

Probably a 5 or 6, it's as much the fuel economy as the increase in highway noise - it drones a bit in 5th but is quiet in 6th. Around town it's less of an issue.

redpoint5 · 07-26-2019, 03:43 PM

If I lost 6th in my stock TSX and couldn't get it back, I'd give the car away. It's already way too short as it is... on second thought, I'd strip it and make a track car out of it. 6th is useless on the track. There isn't a straight long enough to get to it.

Ecky · 07-26-2019, 04:02 PM

Quote:

Originally Posted by redpoint5

If I lost 6th in my stock TSX and couldn't get it back, I'd give the car away. It's already way too short as it is... on second thought, I'd strip it and make a track car out of it. 6th is useless on the track. There isn't a straight long enough to get to it.

Well recall there's the 3.4 final drive. Even taking tire size into account, your 6th is between my 4th and 5th.

redpoint5 · 07-26-2019, 04:09 PM

I know, just trying to relate something that is mostly unrelated. There aren't many TSXs out there, so any topic discussing anything about it has my interest. It's also me reiterating my frustration with the gearing yet again. 6th is useless on the track from a "sportiness" perspective, and nearly useless as a cruising gear since it revs so high. Acura could have left 1-5 for sportiness, and 6th useful for fuel economy, but they didn't. The automatic has a better fuel economy rating due to the better cruising gearing. I get the best fuel economy in stop and go traffic compared to highway cruising.

I'm very impressed with what you've done, and just wish it was "perfect" considering your efforts.

serialk11r · 07-29-2019, 03:20 AM

Wow 65mpg with that engine is amazing. Good aero is nice.

I'm thinking about getting an S2000 as a toy car if some more money lands in my pocket. That thing probably has 2x the drag of your Insight and enough rear lift to lift the rear wheels of your Insight off the ground T_T

Ecky · 08-09-2019, 07:46 AM

Small update: Haven't been working on my car nearly as much as I want to. I bought a house in February and over the last month or so tore an entire side of it off, down to the studs, to replace insulation, sheathing, windows, wrap and siding. Parts of this are time-sensitive and need to be completed during periods where I have both some time off work and a few clear and dry days.

As for the car, I managed to spoof the ECT to stay right in the middle (haven't yet figured out how to properly make it move), took it in for Vermont's very strict state inspection, and had it pass.

I also have been tweaking my fuel maps further on my drive to and from work. I was having an issue where in the mornings it was biased rich, and in the evenings it was biased lean. What I eventually came up with was that intake air temperature was different, and differences in both temperature of the engine and air were able to swing the fuel tables as much as 5-7% in either direction. So, I'm playing with different curves and re-tuning the fuel tables. I don't think the difference observed in the fuel maps is as large as the raw difference in air density, and the difference at low load is different than at high load, plus I have to sort out how much enrichment needs to happen from having cold intake runners and cylinder walls. At those cam openings with a lot of hot EGR happening, the cold coolant enrichment needed is much less. Turns out there's a lot of fine tuning for internal combustion engines, go figure.

California98Civic · 08-09-2019, 08:11 PM

Impressive practice, nonetheless. Those fuel tables sound complex. The more sensor inputs, the more complexity, I am sure.

Ecky · 08-12-2019, 09:17 AM

Got some instrumentation! For the initial tune I divided my injector size by that of one of the Civics referenced in the MPGuino Wiki, and at a glance the fuel economy numbers look to be within a few percent of what I'd expect them to be.

mpg_numbers_guy · 08-12-2019, 11:11 PM

Nice!

I'm guessing MG = Miles per Gallon and GH = Gallons per Hour, but what do the S and C stand for?