Warmup Advance without an Idle Valve, BMW M20

Tuning concepts, methods, tips etc.

Moderators: jsmcortina, muythaibxr

potatomash
Helpful MS/Extra'er
Posts: 50
Joined: Fri Oct 30, 2015 2:04 am
Location: Auckland, New Zealand

Warmup Advance without an Idle Valve, BMW M20

Post by potatomash »

Hi,

Looking for some advice on my warmup settings. MS2 wasted spark running a BMW E30 M20B25 turbo

I have no ICV, so am trying to set the warmup through the warmup advance ignition timing.

Currently it warms up around 600-700rpm, which is a bit low, and I have quite a bit of advance. (Temp is in degrees celcius)

My question is how much is too much? Have attached my current tune. Thanks :)

Image
'88 BMW E30 M20B25 GT3582r, MS2, Mitsubishi GTO wasted spark coils, 630cc injectors, launch control
grom_e30
Super MS/Extra'er
Posts: 4451
Joined: Thu Mar 08, 2012 12:44 pm
Location: UK

Re: Warmup Advance without an Idle Valve, BMW M20

Post by grom_e30 »

you are only adding +6 degree max that's not a great deal. but i believe cold advance adds it across the whole timing table. maybe have a look at rpm based idle advance that way you can ramp extra timing in when you are at tick over only. if the rpms are to low more timing is added and if they are to high it can remove timing to drop the engine speed
1990 bmw 320i daily driver with m20b25 ms3 sequential fuel, 380cc injectors, d585 coil near plug, home made cam sync, launch control, fan control, vss, homebrew egt logging what's next????
potatomash
Helpful MS/Extra'er
Posts: 50
Joined: Fri Oct 30, 2015 2:04 am
Location: Auckland, New Zealand

Re: Warmup Advance without an Idle Valve, BMW M20

Post by potatomash »

Yeah thats what I was worried about for cold advance, too bad you cant limit by rpm.

So use idle advance to drop timing when warm, meaning use higher timing in the ignition table for the warmup cells?

Not quite sure how to make it distinguish between warming up and warm with idle advance.

And don't use cold advance? (Agreed I don't like it because it adds timing everywhere. (Although I guess I could reduce it across the whole table once its warm, although that seems backwards)
'88 BMW E30 M20B25 GT3582r, MS2, Mitsubishi GTO wasted spark coils, 630cc injectors, launch control
grom_e30
Super MS/Extra'er
Posts: 4451
Joined: Thu Mar 08, 2012 12:44 pm
Location: UK

Re: Warmup Advance without an Idle Valve, BMW M20

Post by grom_e30 »

use cold advance but you can limit how much it adds overall.

then use rpm based idle advance always so at your set idle speed say 850rpm it add's 0 advance, if the rpm drops below your target speed it will add x timing to try and speed the engine up, and if the idle speed is above your target it removes x timing to try and slow the engine down. its always active so will adjust the timing to try and keep the engine at your set idle speed.

and do all this without having to change the spark table.




edit: msq
1990 bmw 320i daily driver with m20b25 ms3 sequential fuel, 380cc injectors, d585 coil near plug, home made cam sync, launch control, fan control, vss, homebrew egt logging what's next????
potatomash
Helpful MS/Extra'er
Posts: 50
Joined: Fri Oct 30, 2015 2:04 am
Location: Auckland, New Zealand

Re: Warmup Advance without an Idle Valve, BMW M20

Post by potatomash »

Ok cheers thanks heaps, I'll try that.

So that will effectively give me 6 degrees more at whatever temp at idle for 700rpm, so I may not need cold advance at all, I guess I will try and see.
'88 BMW E30 M20B25 GT3582r, MS2, Mitsubishi GTO wasted spark coils, 630cc injectors, launch control
grom_e30
Super MS/Extra'er
Posts: 4451
Joined: Thu Mar 08, 2012 12:44 pm
Location: UK

Re: Warmup Advance without an Idle Valve, BMW M20

Post by grom_e30 »

yeah that will be active all the time unless the clt is below -10, it will add the extra timing on top of what is set in you main spark table. you may need to tweak the settings a bit but will get your in the ball park, i use my bike like that without an idle valve and it holds the idle pretty much where i want it hot or cold.
1990 bmw 320i daily driver with m20b25 ms3 sequential fuel, 380cc injectors, d585 coil near plug, home made cam sync, launch control, fan control, vss, homebrew egt logging what's next????
potatomash
Helpful MS/Extra'er
Posts: 50
Joined: Fri Oct 30, 2015 2:04 am
Location: Auckland, New Zealand

Re: Warmup Advance without an Idle Valve, BMW M20

Post by potatomash »

So if the rpm during warmup say, is 700rpm, its going to add 6 degrees, wont it just remove that extra advance as soon as it bumps the rpm up to 1000ish..?
'88 BMW E30 M20B25 GT3582r, MS2, Mitsubishi GTO wasted spark coils, 630cc injectors, launch control
grom_e30
Super MS/Extra'er
Posts: 4451
Joined: Thu Mar 08, 2012 12:44 pm
Location: UK

Re: Warmup Advance without an Idle Valve, BMW M20

Post by grom_e30 »

yeah its always active providing the conditions are met eg: tps below 1% rpm less than 1200 and clt greater than -10c ect. so if its the rpm is 900 = 0 extra advance. if rpm is higher than that it will start reducing the timing to bring the rpm back to 900, and if the rpm drops below 900 it will start to add timing to bring the engine speed up. it will constantly vary the timing to maintain 900rpm at all times its active
1990 bmw 320i daily driver with m20b25 ms3 sequential fuel, 380cc injectors, d585 coil near plug, home made cam sync, launch control, fan control, vss, homebrew egt logging what's next????
potatomash
Helpful MS/Extra'er
Posts: 50
Joined: Fri Oct 30, 2015 2:04 am
Location: Auckland, New Zealand

Re: Warmup Advance without an Idle Valve, BMW M20

Post by potatomash »

Ok ill let you know how I go..
'88 BMW E30 M20B25 GT3582r, MS2, Mitsubishi GTO wasted spark coils, 630cc injectors, launch control
potatomash
Helpful MS/Extra'er
Posts: 50
Joined: Fri Oct 30, 2015 2:04 am
Location: Auckland, New Zealand

Re: Warmup Advance without an Idle Valve, BMW M20

Post by potatomash »

I tried it but didnt have any luck, it was pushing like 25 degrees and still stuck around 700rpm. Going to try crack throttle stop a bit more for cold idle and drop warm idle with timing
'88 BMW E30 M20B25 GT3582r, MS2, Mitsubishi GTO wasted spark coils, 630cc injectors, launch control
panel
Master MS/Extra'er
Posts: 663
Joined: Tue Aug 17, 2004 9:56 pm
Location: Victoria B.C. Canada
Contact:

Re: Warmup Advance without an Idle Valve, BMW M20

Post by panel »

potatomash.......try adding some timing like the pic below........if you watch a cold start log you can see where the dot moves from the 100KPA down to where your car normally idles. Add lots of timing up high and taper down to your idle area. Maybe like 30° then interpolate down to your 14°.

Image
'65 VW Bus with a Subaru EJ20 Turbo conversion , Air to water I/C , LS coils , 14Point7 Spartan 2 & Solid Air Fuel Ratio 52mm gauge.
MS2 Extra V3.0 board
potatomash
Helpful MS/Extra'er
Posts: 50
Joined: Fri Oct 30, 2015 2:04 am
Location: Auckland, New Zealand

Re: Warmup Advance without an Idle Valve, BMW M20

Post by potatomash »

So I have this at the moment.. its still not ideal, warmup like 800rpm to about 50 degrees C, then its gets to dead set at 1050rpm for everything else, fan on low or high speed its pinned.

Image
Image

Attached a log
'88 BMW E30 M20B25 GT3582r, MS2, Mitsubishi GTO wasted spark coils, 630cc injectors, launch control
eekoog
Helpful MS/Extra'er
Posts: 43
Joined: Tue Oct 18, 2011 6:24 am
Location: Lyon, France

Re: Warmup Advance without an Idle Valve, BMW M20

Post by eekoog »

Hi man,
Bit of a long shot but have you solved your problem ? I am in the exact same situation. No IAC valve, i want to open the throttle stop a bit so the engine doesn't stall when cold (i have to hold it alive with my foot on the thtrottle at the moment).
And i want to lower its speed when hot with ignition advance.
Success story : Mazda rotary engine 13b peripheral ported, microsquirt V2, full alpha-n.

In the works : Volvo 240 4cyl 2.3, Holset HY35 and MS3x
jsmcortina
Site Admin
Posts: 39587
Joined: Mon May 03, 2004 1:34 am
Location: Birmingham, UK
Contact:

Re: Warmup Advance without an Idle Valve, BMW M20

Post by jsmcortina »

Add an idle valve or at worst a throttle bumper or "choke" mechanism.

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".
potatomash
Helpful MS/Extra'er
Posts: 50
Joined: Fri Oct 30, 2015 2:04 am
Location: Auckland, New Zealand

Re: Warmup Advance without an Idle Valve, BMW M20

Post by potatomash »

eekoog wrote:Hi man,
Bit of a long shot but have you solved your problem ? I am in the exact same situation. No IAC valve, i want to open the throttle stop a bit so the engine doesn't stall when cold (i have to hold it alive with my foot on the thtrottle at the moment).
And i want to lower its speed when hot with ignition advance.
I solved it by warmup ignition advance, and also bit higher timing around idle, and a little more open on the throttle body stop. I had to hold my foot on the gas for about 20-30 seconds when car starts, after that its mint idling everywhere which was fine for me. Had my idle set to around 950-1000rpm
'88 BMW E30 M20B25 GT3582r, MS2, Mitsubishi GTO wasted spark coils, 630cc injectors, launch control
eekoog
Helpful MS/Extra'er
Posts: 43
Joined: Tue Oct 18, 2011 6:24 am
Location: Lyon, France

Re: Warmup Advance without an Idle Valve, BMW M20

Post by eekoog »

Thanks man.
Problem I got is the rpm timing correction doesn't seem to kick in. I refer to the standard Ignition Advance gauge, that doesn't move from the values in the general ignition table.
I put the throttle stop opened enough so that it can hold the engine running on a cold start. Idle was at 900rpm
One hot, it idles at almost 1200rpm which is too much.
I tried to remove 15deg from my general inmgnition table (it idles normally at 18deg) and I could bring the idle speed back to 900.
But I had to do it manually. Nothing seems to happen with the closed loop advance feature.
Success story : Mazda rotary engine 13b peripheral ported, microsquirt V2, full alpha-n.

In the works : Volvo 240 4cyl 2.3, Holset HY35 and MS3x
eekoog
Helpful MS/Extra'er
Posts: 43
Joined: Tue Oct 18, 2011 6:24 am
Location: Lyon, France

Re: Warmup Advance without an Idle Valve, BMW M20

Post by eekoog »

This is how I set it up :ImageImage
Success story : Mazda rotary engine 13b peripheral ported, microsquirt V2, full alpha-n.

In the works : Volvo 240 4cyl 2.3, Holset HY35 and MS3x
eekoog
Helpful MS/Extra'er
Posts: 43
Joined: Tue Oct 18, 2011 6:24 am
Location: Lyon, France

Re: Warmup Advance without an Idle Valve, BMW M20

Post by eekoog »

jsmcortina wrote:Add an idle valve or at worst a throttle bumper or "choke" mechanism.

James
James, do you know what could be the reason for the rpm correction not to kick in ?

I was able to lower my idle only playing with ignition advance so i think i can avoid installing an IAC valve right ?

Thank you for your help.

I attached an msq if that can help.
Attachments
2019-06-26_18.50.16.msq
(287.74 KiB) Downloaded 99 times
Success story : Mazda rotary engine 13b peripheral ported, microsquirt V2, full alpha-n.

In the works : Volvo 240 4cyl 2.3, Holset HY35 and MS3x
potatomash
Helpful MS/Extra'er
Posts: 50
Joined: Fri Oct 30, 2015 2:04 am
Location: Auckland, New Zealand

Re: Warmup Advance without an Idle Valve, BMW M20

Post by potatomash »

Heres my settings

Image

Image
'88 BMW E30 M20B25 GT3582r, MS2, Mitsubishi GTO wasted spark coils, 630cc injectors, launch control
eekoog
Helpful MS/Extra'er
Posts: 43
Joined: Tue Oct 18, 2011 6:24 am
Location: Lyon, France

Re: Warmup Advance without an Idle Valve, BMW M20

Post by eekoog »

Thanks man.
How come i have not the same menu as yours ? I am using MS3x 1.5.0 firmware with TS v3.0.28 :shock:
Success story : Mazda rotary engine 13b peripheral ported, microsquirt V2, full alpha-n.

In the works : Volvo 240 4cyl 2.3, Holset HY35 and MS3x
Post Reply