Timing table too low?

[R/Tony]

Hi guys!

I think I need some help here... can anyone tell me if Im going with the right way with this table?



That is my spark advance table of my car... its a 2.5 8v holset turbo and I come up with this table after watching a lot of knock in the megasquirt, so I pull back the timing to those values, but I think they are wrong, they are too low dont you think?

I am using a VW Bosch knock sensor and the sensibility of the knock system is very adjustable, so maybe I dont have real knock, its just that the system is very sensitive and its detecting engine noise as a knock.

Where I can add more timing? and where I can not?

Does anyone have a similar setup along with a spark table ? ... I want to run safe, but with this table I wont be running I guess

Any help is appreciated !

[Aries_Turbo]

didnt i give you a spreadsheet with the factory timing values?

heres one... http://www.squirrelpf.com/bucar/ecu%...5L%203-bar.xls

you have to convert the kpa values from the MS to psi and input them in the yellow MAPTBL or WOTTBL boxes. then input the appropriate RPM value from the MS timing table and the total timing value will be displayed. if you are using a distributor with a set timing advance, then use the timing value to the left that doesnt have the distributor advance added.

as for the WOTTBL and MAPTBL stuff... i use MAPTBL values for in vacuum and WOTTBL values for in boost.

as for the knock sensor stuff.... unless you have one of those knocksenseMS units, the bosch knock sensor is going to produce too much noise to interface to the MS correctly because it is a widerange sensor. you need a filtering circuit to allow only the frequencies of knock to pass through. for our motors its from 6000-6300hz.

Brian

[R/Tony]

Oh ok thanks!.. I will try to compare the table .. btw I am using neon coil pack (dist-less)

[Aries_Turbo]

ok so you will use the total timing value then.

Brian

[ShelGame]

Brian - Did you see my updated flow chart for the 2.5 T1 timing (T-SMEC timing)? There is another value that affects WOT timing - MAPMUL. This is a multiplier from RPM for the advance from MAP table. In the '89 T2, this value is multiplied by both the P/T and WOT tables. But, in the '89 T1, only the WOT table gets the multiplier. And, the table is very different in shape from the T2 table. You might want to take a look at it. It's why the WOT table looks like it gives you more timing than the P/T table...

[Aries_Turbo]

ill have to check that out. thanks

Brian

[turbovanman²]

Brian - Did you see my updated flow chart for the 2.5 T1 timing (T-SMEC timing)? There is another value that affects WOT timing - MAPMUL. This is a multiplier from RPM for the advance from MAP table. In the '89 T2, this value is multiplied by both the P/T and WOT tables. But, in the '89 T1, only the WOT table gets the multiplier. And, the table is very different in shape from the T2 table. You might want to take a look at it. It's why the WOT table looks like it gives you more timing than the P/T table...

Nice, that's better explained than before. I'll paste this in my thread.

[R/Tony]

Yea.. now that I have seen the stock tables, and the tables from other cars I see that my table its very low, but at least its very safe ... and its better for now because im still learning

Now I have come up with RESET issues after 25+psi... so I need to get rid of it before continue on the tunning process

http://www.turbo-mopar.com/forums/sh...ad.php?t=43835

[turboshad]

I don't think your timing is all that low in the cruise section. Anything above 100Kpa is low for sure. Here is my 91 and 106 tables for the 2.4l DOHC

[TurboII]

I don't think your timing is all that low in the cruise section. Anything above 100Kpa is low for sure. Here is my 91 and 106 tables for the 2.4l DOHC

please help me get this

[turboshad]

Can some one explain this to me what each line mean? please i wanna learn how to tune my own cal

Joey

The X-axis is RPM and the Y-axis is manifold pressure in KPa. So 100KPa ~ atmospheric. Anything above this level is boost and anything below is cruise/vac. The numbers in each cell denote the timing advance put out by the megasquirt. If you are running distributorless then this is the total advance. If you are running a distributor then you need to add your base timing to this number to get the total advance.

[R/Tony]

The X-axis is RPM and the Y-axis is manifold pressure in KPa. So 100KPa ~ atmospheric. Anything above this level is boost and anything below is cruise/vac. The numbers in each cell denote the timing advance put out by the megasquirt. If you are running distributorless then this is the total advance. If you are running a distributor then you need to add your base timing to this number to get the total advance.

Hey DJ .. Im glad you saw this post ! because the VW Bosch knock sensor was somehow your idea

I saw your project log -very impressive I have to say- and I liked the way you are checking knock so I copy you ... Right now with this table I cant hear any knock, well... I cant hear any bad noise or something like that so I think im safe, and for testing porpouses I dont want to move too much of this spark table, but how can I tell if what I am actually hearing is knock and not any other engine noise?

By any chance do you have a sound record of your car running with and without knock ? .. I guess the knock on a 2.4 DOHC its diferent from the 2.5 SOHC, but I can get an idea.

Thanks !!

[TurboII]

The X-axis is RPM and the Y-axis is manifold pressure in KPa. So 100KPa ~ atmospheric. Anything above this level is boost and anything below is cruise/vac. The numbers in each cell denote the timing advance put out by the megasquirt. If you are running distributorless then this is the total advance. If you are running a distributor then you need to add your base timing to this number to get the total advance.

so if i have a distributor my base timing would be 12^ correct?

[turboshad]

I can't lay claim to finding the bosch sensor since it was Tjabo on neons.org that tipped me off. I just did some leg work to find some easily atainable part numbers from the VWs. I also wondered if I would actually recognize the knock when I heard it but I found it very distinct and un-mistakable. On my engine there is a quite tick with little to no load that varys of course with RPM. When cruising and I load it up I get a lower frequecy "knock" sound. At first I thought that it was a low level knock or something and I tried to tune it out but it never really went away and my ignition map was through the floor. I've come to realize that this lower frequency sound isn't anything to worry about and I think it is just the sound when the engine gets loaded up. Once into boost and climbing in RPM I get a smooth sound that is more of the tick than the lower "knock" sound. If it pings/knocks under boost it is a very high frequency unlike anything else in the mix. It actually sounds like a high pitched ping or scratching noise and you'll know right away. The cool part is you will hear it waaaaaaay before you can with your ears over the sounds in the cab. So if you are catching it at that level you are more than safe.

I know it's pretty hard to describe sounds but hopefully you get it a bit. Unfortunately I haven't personally recorded any of my tuning yet but here is one recording by opel on the org. You can here the high pitched "ticking" that isn't like anything else in the clip. He starts in first gear and it happens once in second, a bit spuratically through third and once he hits fourth it is very prevalent. Hopefully that helps a bit.

The clip:
http://go2pcfix.com/downloads/msdrag...run%201581.wav

The thread on neons.org with the clip on the top of page 3 and the bosch flat repsonse sensor being introduced near the middle of page 3.
http://forums.neons.org/viewtopic.php?f=60&t=295450

[turboshad]

so if i have a distributor my base timing would be 12^ correct?

If you are running a distributor with megasquirt you can set the base timing to whatever the heck you want. If you want a total of 28deg and you have a base fo 12 you would enter 16 in that given cell. If you have a base of 2 then enter 26 etc.

[TurboII]

so what are you guys using for tuning software

[turboshad]

so what are you guys using for tuning software

... megasquirt,...

... megasquirt...

...megasquirt..

I'll give you one more guess.

[TurboII]

megasquirt has a software program?

[Aries_Turbo]

yeah its called megatune... and its only for megasquirt.

[Ondonti]

skeeeeeeeeeeeeeeeeeeeeeeeeeeeeeeee


sorry.

How are you inter facing this knock sensor? Sounds like the kinda useless knock sensor I don't want. Excited for Brians project. I just finished making a microphone setup tonight for listening to knock on my car so if I do any tuning I will have that to rely on.
I want to use Megasquirts ability interface with a 0-5v knock signal and set thresholds etc. Even though for me the best tune will be one that almost never knocks...

BTW, you guys have wayyy too much timing at your starting rpms. OP you need to work on your breakdown of rpm points. 500 rpms is not necessarily the best breakdown. Its more important to capture the RPMs where VE changes the most or during peak torque (for precise spark tuning).

Turboshad, how does your car start with all that timing? Mine was a rough start. I just did some reading and it seems when starting you should only have 4-12 degrees for best start. I didnt go that far but I knocked a lot of timing off my 1000 rpm plot near starting vacuum level. I also knocked some timing off at the higher vacuums (30-60kpa) because your idle will be smoother with less timing and more fuel, less likely to stumble/stall etc. Have not tried it yet though. Just what I read in the megamanual a few nights ago while pounding my head against the knock sensor situation. I modified my maps but I have things torn apart right now

I don't have a plot below 1000 rpms because I am trying to use the resolution where its more important to me. I also don't have any decel load points. I can just set decal to remove fuel by % (though I am not doing any of that while working on my ve maps). The problem with not having a plot near starting speed is that timing will be too high for starting and sub 1000 rpm running, and more sluggish throttle response at 1000 rpms if you drop timing to make up for it.

Of course if I ever go "extra" for the 16x16 tables I would probably still not dedicate load sites to decel or sub 1000 rpms.
I actually skip from 2000 to 3000 rpms and the car still runs great right there. 2000 to 3000 is my OEM torque peak so there really isnt much difference in there and 3000 the boost will start building slowly so from there on I hit 500 rpm intervals for simplicity's sake but its not necessarily the best breakdown. .