Cranking Advance vs Cold Advance

This is a forum for discussing the development and testing of alpha MS2/Extra code. Documentation
(Runs on MS2 and Microsquirt)

Moderators: jsmcortina, muythaibxr

Post Reply
gslender
Super MS/Extra'er
Posts: 1072
Joined: Fri Sep 16, 2011 5:29 am
Location: Brisbane, Australia
Contact:

Cranking Advance vs Cold Advance

Post by gslender »

Just wondering....

In the current MS2 code, the cold advance does not apply to the cranking advance, only once out of cranking and in engine ready/run.

Is that right? Should the cold advance only apply when running? Why wouldn't you want to have the increasing advance applied at cranking? It would seem logical that if the engine runs better with more advance when cold, wouldn't that apply in cranking? ...or is the logic to essentially have the maximum possible advance at cranking anyway and that more (or less when warm) doesn't help.

G
Mazda MX5 + MS3 Pro
jsmcortina
Site Admin
Posts: 39587
Joined: Mon May 03, 2004 1:34 am
Location: Birmingham, UK
Contact:

Re: Cranking Advance vs Cold Advance

Post by jsmcortina »

The "cold advance" is perhaps a misnomer.
In another source I read that
-in a race car, advance when cold due to high-lift cams etc.
-in a car with a catalyst, retard when cold to increase exhaust temps and light up the cat.

Cranking isn't trying to do either of those and too much advance risks kick-back.

James
I can repair or upgrade Megasquirts in UK. http://www.jamesmurrayengineering.co.uk

My Success story: http://www.msextra.com/forums/viewtopic ... 04&t=34277
MSEXTRA documentation at: http://www.msextra.com/doc/index.html
New users, please read the "Forum Help Page".
piubrazil
Helpful MS/Extra'er
Posts: 83
Joined: Sat Feb 28, 2009 6:16 pm
Location: Sao Paulo - Brazil

Re: Cranking Advance vs Cold Advance

Post by piubrazil »

A cold advance cranking curve ( or whatever it could be named) would be very useful for the guys who runs 100% ethanol (80% of the cars here in Brazil). The cold crank in gasoline or even E85 doesn't need more advance than 6-12 degrees in cranking to have a solid start, but an engine runnign E100 need up to 35-40 degrees to start under 20ºC ambient. But this level of advance cause kickbacks in hotstarts, obviously. Unfortunattely we have to live with a more than ideal advance to hotstarts and less than ideal in coldstarts. I already had some broken starters due to kickbacks in engines running MS2.

I would be very glad if a cranking advance versus temperature curve where placed in the to do list.
Luiz Henrique - Piu
São Paulo
Brazil
gslender
Super MS/Extra'er
Posts: 1072
Joined: Fri Sep 16, 2011 5:29 am
Location: Brisbane, Australia
Contact:

Cranking Advance vs Cold Advance

Post by gslender »

There is a bit of incidental information on Google to suggest that more advance when cold cranking is helpful, and less during warmer cranking. Would be easy to adapt the existing cold starting advance to be applied/added to the cranking advance too!

G
Mazda MX5 + MS3 Pro
piledriver
Super MS/Extra'er
Posts: 1679
Joined: Tue Oct 27, 2009 6:24 am
Location: Van Alstyne, Texas

Re: Cranking Advance vs Cold Advance

Post by piledriver »

gslender wrote:There is a bit of incidental information on Google to suggest that more advance when cold cranking is helpful, and less during warmer cranking. Would be easy to adapt the existing cold starting advance to be applied/added to the cranking advance too!

G

It would probably be well worth it, but it needs more range than current 10 degrees max for many applications.
Always doing things the hard way, MS2 sequential w/ v1.01 mainboard, LS2 coils. 80 mile/day commuter status.
magaiverbrasil
Helpful MS/Extra'er
Posts: 38
Joined: Tue Jul 19, 2011 4:12 am
Location: Rio de Janeiro - BRAZIL

Re: Cranking Advance vs Cold Advance

Post by magaiverbrasil »

I have , ms2 and ms3 , and i use 100% alcohol , i would like to have this implementation , crank advance for temperature.
Vw Santana AP 2.0 - MSII PCB3.0 Extra 3.2.1
pepeleascov
MS/Extra Newbie
Posts: 6
Joined: Wed Jan 07, 2015 4:30 am

Re: Cranking Advance vs Cold Advance

Post by pepeleascov »

This would be an interesting feature, for those who run E85 or E100 blends.
It will REALLY improve the cold starts!
VW Passat 1.8T 20v @ 16psi - Custom manifolds - MS2
magaiverbrasil
Helpful MS/Extra'er
Posts: 38
Joined: Tue Jul 19, 2011 4:12 am
Location: Rio de Janeiro - BRAZIL

Re: Cranking Advance vs Cold Advance

Post by magaiverbrasil »

Do they have any prediction to insert this into the code?
Vw Santana AP 2.0 - MSII PCB3.0 Extra 3.2.1
webthiago
MS/Extra Newbie
Posts: 1
Joined: Sat Aug 26, 2017 7:49 am
Location: São Paulo/Brazil
Contact:

Re: Cranking Advance vs Cold Advance

Post by webthiago »

I have one ms2. Please add this to the code.
Benetti
MS/Extra Newbie
Posts: 1
Joined: Mon Sep 04, 2017 5:26 pm

Re: Cranking Advance vs Cold Advance

Post by Benetti »

I have a MS2, and I would like to have this implementacion!
magaiverbrasil
Helpful MS/Extra'er
Posts: 38
Joined: Tue Jul 19, 2011 4:12 am
Location: Rio de Janeiro - BRAZIL

Re: Cranking Advance vs Cold Advance

Post by magaiverbrasil »

any prediction for this? It's winter in Brazil, the cold start is very difficult :-(
Vw Santana AP 2.0 - MSII PCB3.0 Extra 3.2.1
igor.rodriguez
MS/Extra Newbie
Posts: 1
Joined: Wed Jun 28, 2017 7:59 pm

Re: Cranking Advance vs Cold Advance

Post by igor.rodriguez »

Hello! Good night everybody! Is there any forecast to implement this fix in code?
magaiverbrasil
Helpful MS/Extra'er
Posts: 38
Joined: Tue Jul 19, 2011 4:12 am
Location: Rio de Janeiro - BRAZIL

Re: Cranking Advance vs Cold Advance

Post by magaiverbrasil »

They do not care about us, they forgot about us. :(
Vw Santana AP 2.0 - MSII PCB3.0 Extra 3.2.1
magaiverbrasil
Helpful MS/Extra'er
Posts: 38
Joined: Tue Jul 19, 2011 4:12 am
Location: Rio de Janeiro - BRAZIL

Re: Cranking Advance vs Cold Advance

Post by magaiverbrasil »

we will continue to be ignored?
Vw Santana AP 2.0 - MSII PCB3.0 Extra 3.2.1
piledriver
Super MS/Extra'er
Posts: 1679
Joined: Tue Oct 27, 2009 6:24 am
Location: Van Alstyne, Texas

Re: Cranking Advance vs Cold Advance

Post by piledriver »

I suspect someones going to have to code it on the previous version and hope the devs import it.

folks running e100 are few and far between here, even all my local e85 pumps have been converted to e15 pumps, which no one will likely never intentionally use.
Always doing things the hard way, MS2 sequential w/ v1.01 mainboard, LS2 coils. 80 mile/day commuter status.
magaiverbrasil
Helpful MS/Extra'er
Posts: 38
Joined: Tue Jul 19, 2011 4:12 am
Location: Rio de Janeiro - BRAZIL

Re: Cranking Advance vs Cold Advance

Post by magaiverbrasil »

here in brazil all pumps are E100, and all that have turbo car use E100
Vw Santana AP 2.0 - MSII PCB3.0 Extra 3.2.1
Matt Cramer
Super MS/Extra'er
Posts: 17499
Joined: Thu Apr 16, 2009 8:08 pm

Re: Cranking Advance vs Cold Advance

Post by Matt Cramer »

Your best bet to make a case for temperature dependent cranking advance would be to gather data logs of cranking at different advances and temperature to demonstrate better starting at different temperatures with different amounts of timing.
Matt Cramer -1966 Dodge Dart slant six running on MS3X
Hackao
MS/Extra Newbie
Posts: 2
Joined: Fri Aug 28, 2015 2:01 pm

Re: Cranking Advance vs Cold Advance

Post by Hackao »

Could you please implement this function? Would help us alot, that run E100.
Post Reply