Lean burn mode rules 64.8mpg

[pgfpro]

Originally Posted by greasemonkee

I was playing with a d15z1 last week and I noticed it required considerably more manifold pressure to maintain constant speed or accelerate. This should be the rule, plus you eliminate some pumping loss by having the throttle closer to 100%.

As a safety precaution, I would definitely limit pressure columns up to around 650 mbars in that super lean mode. I normally transition back to stoichiometry at around 600-650 mbars as seen in table below.

My ugly, fuel wasting low cam target:



This same engine when NA did much better running lean oddly enough, hence the mild 15.2 target.


Have you considered finding a straight, constant grade and traveling it while shifting the timing gradually (as well as afr) to find the lowest injector duration that you can achieve? I would graph out the data (provided Neptune can do graphs) and see if there are any trends on the same section of road at the same speed every time. If you had an economy meter (or something to juggle the data and spit out a relative mpg in the software?), you might could go by that possibly?

Just be sure to hold your IAT's constant, among other variables, to make it easy on you, but you probably are well aware of the concept.

I need to find a hill like you said and do some more testing. Thanks for the idea.

Heres my fuel map;



The highlighted areas are my lean burn cells. This is what had me stoked. Its still making great power at these lean conditions. So when I go to 23:1 A/F it moves it over to the right one column. I just need to try it to see what happens. I guess LOL

[pgfpro]

Heres a pic of the engine bay;



Well I have to postpone my testing until it stops raining.

[pgfpro]

I was wondering if I did a Pulse and Glide type driving, would it help or be a detriment to my FE?

As of right now I'm just driving with a steady state throttle.

[pgfpro]

Ok I did some more testing. I got it to run at 23:1 A/F ratio

"Party on Garth"

[tigerbyte]

Aww you make me miss my del sol. i really need to get a new motor for it.

have you done any aero mods on the del sol or is it all fuel maps?

[naturalextraction]

pgfpro, could you show your map charting/readout for your latest A/F reading? How was the power at that ratio and how are you measuring it? Have you tried this on a dyno?

[pgfpro]

Originally Posted by tigerbyte

Aww you make me miss my del sol. i really need to get a new motor for it.

have you done any aero mods on the del sol or is it all fuel maps?

Still testing the temporary crash wrap mods. I just need to figure out how far I want to go with it (kamm back or boat tail).

I finally got it to run at 23:1 and still make good power. Now I'm looking at installing a EVOIII 16g turbo before winter hits. The 15G turbo works so well I'm scared to mess with it.LOL

I hit a new personal best This was done with the FMIC bypassed. So now I'm going to permanently remove it this weekend. When I race the car it will be on E85 so there is no use for it anyway.

If your looking at different engine and still want good power I would recommend my setup.

I have been working on this combination for the last 6 years. In the beginning I was told it won't work because of the low compression (7.5:1) This engine can easily be turned over by hand.

With a FI system and the right combustion chamber and the correct piston and rod combination it can be done.

[pgfpro]

Originally Posted by naturalextraction

pgfpro, could you show your map charting/readout for your latest A/F reading? How was the power at that ratio and how are you measuring it? Have you tried this on a dyno?

I haven't recorded any of the 23:1 A/F readings on the LMA-3. I have been working with timing and fuel tables and individual fuel trims on my laptop while watching the LMA-1 A/F hand help unit. ( It looks like someone dump a plate full of spaghetti in my car)

I only have one laptop and it can only read one thing at a time. So I need the Neptune management running so I can make adjustments in RTP.

My PLX A/F gauge will only go as lean as 19:1 A/F, so its useless and reads the word "lean" anything past 19:1. So I then rely on the Innovate wide-band.

As far as power goes its not much. This is done on the freeway at 55mph to 58mph anything faster it needs more fuel and drops to 18.5 A/F. But at 23:1 A/F its enough to keep the car moving at these speeds.

I have access to two dyno's a "Mustang" dyno and a "Dyno" Jet. My first prototype engine made 288whp and 217ft/lbs of torque at 14psi running a A/F ratio of 11.8 on pump fuel.

EDIT I just noticed you want WHP at 23:1 A/F. I don't know what it makes at this level? I would guess 20whp but thats just a guess?

[naturalextraction]

Sounds about right. I'm impressed with the operating parameters of that system. It seems as though you've managed to develop some modifications of your own in order to get some of the read out and results. Allways continue to devise methods that provide as much accuracy as possible! That separates you from thousands of those with unsubstantiated claims and or ridiculous means in which to quantify or "prove" their results. My Kudos to you and my I encourage you to continue to develop accuracy in your testing.
Stay in touch. I'd like to know more about your testing and experiments.
Our testing at the labs got moved till Feb of 2010. I have much data to compile on our system and I was looking forward to testing. Now I guess next year.

[pgfpro]

Originally Posted by naturalextraction

Sounds about right. I'm impressed with the operating parameters of that system. It seems as though you've managed to develop some modifications of your own in order to get some of the read out and results. Allways continue to devise methods that provide as much accuracy as possible! That separates you from thousands of those with unsubstantiated claims and or ridiculous means in which to quantify or "prove" their results. My Kudos to you and my I encourage you to continue to develop accuracy in your testing.
Stay in touch. I'd like to know more about your testing and experiments.
Our testing at the labs got moved till Feb of 2010. I have much data to compile on our system and I was looking forward to testing. Now I guess next year.

Thanks again you have been most helpfull.

That sucks you have to wait until next year.

One of the things you mention was that the turbo is doing a lot more then I thought it was as for FE and controlling combustion. This is something I didn't think about and did some ABA testing to confirm it. Lets just say without the turbo my engine would eventually be burned down.LOL

I have been keeping a ton of logs and information as I make changes. I will eventually show this as I put it all together. Right now I'm trying to get as many miles in as I can because the winters up here are tough and snow is just around the corner. Plus one thing that really frustrates me is how my mileage is so temperature sensitive.

One more thing I want to do is let someone borrow the car I can trust and have them drive it a couple thousand miles and keep track of the fuel mileage. This will take me... the owner out of the equation.

I'm going to do a write up on all my mods this winter with a ton of pics.

I ran into this to be honest by mistake.

It all started with a Pat Musi BBC 565CI nitrous motor. Its a trick the Pro Mod guys did to run a leaner nitrous to fuel ratio. They did this because when you start running multiple systems fuel starts to puddle in the intake runners and make the engine go lean.

I then applied it to my Honda motor that was turbo charged with nitrous. One day coming back from the track I noticed that the wide band gauge was reading extremely lean but the engine ran fine. I later found out I had a clog fuel pump filter. So I fix that and decided to see if it would run that lean again or was I just imaging it. So I took a ton of fuel out of it with my Haltech system and it ran great. Then it got my curiosity and it was time to check the fuel mileage and I was amazed.

Anyway enough rambling.