2G Setting Base Ignition Timing on 6 bolt swap

[larryd]

How do you set the base ignition timing on a 2nd gen that has a 6 bolt block with a 1st gen adjustable CAS. I know on the 1st gen you have a wire that you can ground and it stops the timing from jumping all over the place at idle but since the 2g wasnt meant to have adjustable base ignition timing there is no such wire. Also what should the base ignition timing on a 2g be set at?

I have a feeling that my base igntion timing is off pretty bad and thats why my timing on the car is soo horrible because its already to far advanced.

 

[steve]

The 1G CAS in 2G VFAQ suggest you use a logger and adjust the CAS until the logger timing and the actual timing from the front cover match. Hopefully at idle fully warmed up the ECU isn't shifting the timing around too much.

Steve

 

[talonted_one]

actually if im not mistaken if you have a 6bolt swap you can adjust your base timing the same as a 1g. I might be wrong tho.

My 2G has that wire that you are talking about so I dont see why you wouldnt. But then again I do have a VERY early 95.

our base timing should be set at 4 or 5* base timing.

 

[larryd]

well according to the dsmlink my timing at idle is reading 8-12.. I dont know if this is the right value im looking for or not. I havent actually used the timing light on it yet but im sure its going to be high. Which way do i adjust the CAS to go lower?

 

[steve]

I'm not up to speed on dsmlink's, but I don't think they can tell any better than a normal ECU what the actual timing is. The adjustment is push it down to advance, pull it up to retard the timing. Based on what's in the VFAQ I'd aim to make the actual timine match as closely as you can to what the dsmlink says it thinks the total timing is and then the base timing should match what ever the design was.
On a 1g that works out to a base or 5 degrees BTDC with the adjustment wire attached or about 8 BTDC at 750rpm idle with it off more advace at higher alts. I'm at about 600 ft so my timing is right on 5 BTDC.

Steve

 

[Kevin Jewer]

The ECU assumes 5* base no matter where it is set. Matching the timing light number to the logger will work at any number, but it usually bounces around at idle making it hard to hit the moving target. On early 2Gs there is a brown plug on the firewall by the cruise control that you ground to get the ECU to stop fluctuating idle and hold it steady at 5. Helps a lot. On cars without this terminal, rumor has it that you can unplug the TPS to hold timing, but I havent tried this yet. Supposedly it also prevetns the ECU from going to closed loop control of idle speed making it wasier to properly set the BISS... Maybe I'll try that today before I go to the track.

Some poeple set it to 5 degrees base, other set it higher for more advance. With DSMlink you want it at 5 so your timing numbers in teh logs are correct, and if you want more obviously just dial it in with the DSMlink controls.

 

[larryd]

so if I can determine what is then, which way to i adjust the CAS to lower or raise it?

 

[steve]

Originally posted by larryd
so if I can determine what is then, which way to i adjust the CAS to lower or raise it?

I thought I just posted that.

Steve

 

[larryd]

duh.. i read it and it didnt register.. thanks

 

[BatmanGSX]

Always just set it to 5. People who go higher, like 10, often have unexplainable knock problems.

 

[larryd]

what about below 5?? I have unexplained knock issues and Im trying to get rid of them.. Im thinking about setting base ignition timing at 0 if thats possible.

 

[Kevin Jewer]

That would give you 11 degrees maximum timing advance. I dont think you want that. The car would feel like #@%#@%#@%#@%. If there is a specific rpm that is troublesome take timing out that DSMlink of yours... Thats why we bought it, fuel and timing control

 

[larryd]

i would love to but it doesnt work.. I cant incrase the timing on dsmlink or retard it for the most part.. I get knock with it set at 0 and when I retard it all the way back to -5 timing Im still knocking sometimes. Im getting like no timing advance either.

 

[Kevin Jewer]

Put a timing light on it to make sure youre at 5 degrees. A frind of mine bought a 1g and for a year he didnt know that his base timing was at 35 degrees, . Once we logged it a saw that he got knock constatly no matter what I did, I knew to check base. Try that as soon as possible. Cheap timing lights are only 20 bucks if you dont have one.

Another thing to consider, I can make a pull and have no knock, make another later on and get 2 degrees pulled. I be getting constant knock, lean out some, and it goes away, etc. Its not the hard, fast number we sometimes want it to be. In fact, after extensive tuning at the track this week and last, I learned that I get the best times with 1-2 degrees on knock retard. Zero knock is a good bit slower. Go figure

 

[95GST]

95GSXracer (Kevin) has told you what you needed to know already.

If you don't have the timing ground plug (luckily 95's have them and makes it real easy ), adjust your DSMLINK graphical display to faster refresh rate, see the timing it should jump around and you take an average in your head. Then you point the timing light and adjust it roughly there.

Let's say you see it bounce around 8-12 degrees on DSMLINK display (gotta be on fast refresh rate to see this nicely), then you use take a mental average around 10 degrees. Now adjust your CAS so that it jumps between 8-12 degrees on the crank pulley with a timing light.

That will make your ECU match the timing close to the "assume" 5 degree base timing.

Not a lot of reason to increase base beyond 5 degrees because you can add timing with DSMLINK, and when you add it via DSMLINK it will show up in the logs, if you advanced base timing beyond 5 the DSMLINK will not know and you always have to add the extra advance everytime you read the logs.

 

[larryd]

thanks for the info..ill try to get a timing light on it today.

 

[gsxotic]

Ok tell me if this makes any logic.

I have recently put a 6Bolt in my 2G I have the cas, and looking with a light my timing is around 11 or 12. My idle is also high 1500RPM. So what do I ground to change the timing. We turned it down to 5 with the light (which totally fixed the idle) but as soon as you re-set the car it goes back up to . Any help would be appriciated!