Dual fuel alternate acceleration feature

Testing and development of Megasquirt 3

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vtux
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Dual fuel alternate acceleration feature

Post by vtux »

I noticed that EAE 2 are for staged injection, but can it be enabled to use in dual fuel also in feature firmware? I think it could be great feature for different fuel users like lpg. Is it hard to do this option? It could be easier than different pump or time acc maps i guess.
hardline
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Re: Dual fuel alternate acceleration feature

Post by hardline »

Could also help on E85 when cold, as the vapor pressures are vastly different between E85 and Gasoline.
2000 ZX2 : Sequential COP, MS3 + MS3X + TinyIOx, PWM Returnless Fuel, Flex Fuel, Variable Geometry Intake Manifold, Garrett GTX2863R .82AR housing @ 15 psi
vtux
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Re: Dual fuel alternate acceleration feature

Post by vtux »

I am using E85 as primary and LPG as secondary fuel, and i have a big problem with acc. E85 needs a lot acc, LPG needs almost none. How can I solve this problem?
ds23man
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Re: Dual fuel alternate acceleration feature

Post by ds23man »

I am experiencing the same thing. Currently running MS2extra and want to upgrade to MS3 and this feature would be very nice!
piledriver
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Re: Dual fuel alternate acceleration feature

Post by piledriver »

I was wondering how to automagically deal with the extra fuel E85 needs for cold start and warmup myself today, and it was only ~70 this AM.

If I had more gasoline % it would flood it, but at least the flood clear works... the warm up might be an issue.

The sensor and the related features deal with most of the issues but not quite everything.
Always doing things the hard way, MS2 sequential w/ v1.01 mainboard, LS2 coils. 80 mile/day commuter status.
Matt Cramer
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Re: Dual fuel alternate acceleration feature

Post by Matt Cramer »

I would recommend implementing this too. An engine that runs on gasoline and CNG will need the AE pretty much turned completely off when running on CNG, for example.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Marek
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Re: Dual fuel alternate acceleration feature

Post by Marek »

In some ways, what this shows is that dual fuel users really want almost everything doubled up and table switched.

In this particular case, EAE and simple AE are available - presumably EAE with its wall wetting features is nonsensical to a propane i.e."gas" user, but makes sense to a petrol, i.e. "liquid" user. If these were both available but on a tableswitched basis then that'd make probably solve it, yes?

kind regards
Marek
piledriver
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Re: Dual fuel alternate acceleration feature

Post by piledriver »

With E85 you would probably want a dual table blend (prime, cranking and WUE, as well as accels), or multiplier for each based on ethanol %
(the former likely far closer to ideal but much more work)
Always doing things the hard way, MS2 sequential w/ v1.01 mainboard, LS2 coils. 80 mile/day commuter status.
ds23man
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Re: Dual fuel alternate acceleration feature

Post by ds23man »

For "gas" users a simple switch off AE with tableswitch should solve the problem!!!!!
ds23man
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Re: Dual fuel alternate acceleration feature

Post by ds23man »

Maybe James can tell if this feature will be intergrated?
Matt Cramer
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Re: Dual fuel alternate acceleration feature

Post by Matt Cramer »

Marek wrote:In some ways, what this shows is that dual fuel users really want almost everything doubled up and table switched.

In this particular case, EAE and simple AE are available - presumably EAE with its wall wetting features is nonsensical to a propane i.e."gas" user, but makes sense to a petrol, i.e. "liquid" user. If these were both available but on a tableswitched basis then that'd make probably solve it, yes?

kind regards
Marek
That's pretty much what the underlying physics requires. Different fuels will adhere to the walls and evaporate from the walls at different rates depending on their volatility, surface tension, and viscosity. So anything related to warmup and AE is going to be different if there's anything substantially different between the fuels.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
fpvmustang
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Re: Dual fuel alternate acceleration feature

Post by fpvmustang »

would be nice I'm dual fuel lpg and pump gas. I'm thinking of doing to two more dual fuel street cars. smog exempt. lpg is $1.90 a gallon vs $4. for 87 pump.
33 psi boost on lpg
Marek
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Re: Dual fuel alternate acceleration feature

Post by Marek »

bump
piledriver
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Re: Dual fuel alternate acceleration feature

Post by piledriver »

piledriver wrote:With E85 you would probably want a dual table blend (prime, cranking and WUE, as well as accels), or multiplier for each based on ethanol %
(the former likely far closer to ideal but much more work)

All desired features mentioned are in MS3Pre1.4 code and blend tables between E85 and E0 maps, as well as much more dual fuel goodness.that was
Was working well, although I have not run e85 since winter hit due to overcooling.
Always doing things the hard way, MS2 sequential w/ v1.01 mainboard, LS2 coils. 80 mile/day commuter status.
Matt Cramer
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Re: Dual fuel alternate acceleration feature

Post by Matt Cramer »

Yep, 1.4 has acceleration enrichment blending for flex fuel applications. We have been testing it on a Miata equipped with a flex fuel sensor and trying to squeeze OEM-level drivability out of it no matter what's in the tank or how cold the weather gets. It helps that we've had an unusually cold winter by Atlanta standards.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
ds23man
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Re: Dual fuel alternate acceleration feature

Post by ds23man »

Bump
ds23man
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Re: Dual fuel alternate acceleration feature

Post by ds23man »

Maybe James can tell if this feature will be intergrated?
piledriver
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Re: Dual fuel alternate acceleration feature

Post by piledriver »

It's been in the pre1.4 alphas and betas, and as 1.4 is scheduled to become "release" any day I expect so.
(i cant spel)
Last edited by piledriver on Sun Mar 22, 2015 11:23 pm, edited 1 time in total.
Always doing things the hard way, MS2 sequential w/ v1.01 mainboard, LS2 coils. 80 mile/day commuter status.
ds23man
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Re: Dual fuel alternate acceleration feature

Post by ds23man »

Thanks!
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