ZCar Forum banner

Status
Not open for further replies.
1 - 2 of 2 Posts

·
Registered
Joined
·
107,695 Posts
Discussion Starter #1
I've posted this problem before. As usual, I'm having problems calibrating my Tec II for my 82 280zx turbo. These are settings I've been playing around with:
- TOG = 7 to 8.5 (Is this too high?)
- IOT = 0 to 2
- Min Turn on Time = 0 (I just read something that said it should be set to at least 1.3 before fuel is injected. I haven't tried this yet.)
- Divide by # = 2
I'm starting to play around with the suggested spark advance table that's provided with the Tec manual. How has everyone else gotten this?
Otherwise, most of my other settings are set to 0 (choke enrichments, warmup, etc.) I figure I'll do this once the engine is actually running. Other settings that can't be set to 0 are set (failure parameters, Map bar sensor = 2, etc.)

Is there anything wrong with the settings above ?

By the way, if you're out there Tim Z, yes, I've been fouling plugs.

Thanx
Scott
 

·
Registered
Joined
·
382 Posts
Re: Tec II settings (long)

> I've posted this problem before. As usual,
> I'm having problems calibrating my Tec II
> for my 82 280zx turbo. These are settings
> I've been playing around with:
> - TOG = 7 to 8.5 (Is this too high?)
> - IOT = 0 to 2
> - Min Turn on Time = 0 (I just read
> something that said it should be set to at
> least 1.3 before fuel is injected. I haven't
> tried this yet.)
> - Divide by # = 2
> I'm starting to play around with the
> suggested spark advance table that's
> provided with the Tec manual. How has
> everyone else gotten this?
> Otherwise, most of my other settings are set
> to 0 (choke enrichments, warmup, etc.) I
> figure I'll do this once the engine is
> actually running. Other settings that can't
> be set to 0 are set (failure parameters, Map
> bar sensor = 2, etc.)

> Is there anything wrong with the settings
> above ?

> By the way, if you're out there Tim Z, yes,
> I've been fouling plugs.

First off, which TEC software are you using? PAFZ or SuperB?

Also, what size injectors are you using? FPR pressure? Stock cam?

I'm assuming that your TEC is capable of doing the phased sequential injector firing mode. If so , then you will need to set the divide by to 1 and the firing mode to alternate to get the phased sequential firing (this works the best for me). Your TOG and IOT settings sound like they are in the ballpark, but I'd need to know the above info before I could say with a little more certainty.

I'm currently at TOG=12.3 and IOT = -1.5, with a 3bar MAP sensor, and 50lb/hr injectors. If you multiply my numbers by 2/3 to compensate for your 2bar MAP, they look pretty close to your numbers. My TOG setting is a little on the rich side, BTW.

As far as the advance table, I'd suggest mimicking the stock advance curve, for starters. People seem to get really hung up on the fact that there are 64 load points to fill in - they don't ALL have to be different...

Let's say that you are going to run 14psi of boost (approx 200 kPa) max. Your distributor used to be set up for, say, 10 degrees initial advance, 35 degrees total, all in by 3000 RPM. Just to make it more realisitc, let's say you want to pull out 1 degree of timing for every 1psi of boost.

To accomplish this, first set up your RPM and MAP breakpoints. Pick RPM and MAP breakpoints that make sense for you - maybe 1000, 1500, 2500, 3000, 4000, 5000, 6000, 7000. This gives you a little more resolution around idle and your cruising RPM. Pick your MAP points similarly - my car rarely gets below 60kPa, so I'd go with 60kPa for the first point, 80kPa for the second, and 100kPa (this is approx. 0 vacuum) for the third. Try just evenly spacing them from there to 200kPa. (okay, I guess this works out to every 20kPa, duh)

Now you can set the advance curve. First, just set up the base distributor curve. The entire 1000 RPM column, as well as the initial advance setting should be set to 10deg, per the above requirements. I'd go ahead and set the 1500 column to 10 degrees, as well - this will keep your timing rock solid at idle. Now from 1500RPM to 3000 RPM you need to go from 10 degrees to 35 degrees, a change of 25 degrees in a 1500RPM span, or 8.33 (25/3) degrees every 500RPM.
So, you would want to set the 2000RPM column to 18.33, the 2500RPM column to 26.66, and everything else to 35 degrees.

Next, do the boost retard of 1degree/psi of boost. Your MAP breakpoints are every 20kPa, whci equates roughly to every 3psi. So, for the row corresponding to 120kPa, subtract 3deg from each value in that row. For the 140kPa row, subtract 6deg, and so on.

This should be good enough to get you going. Once you have a stable starting point, you can start adding in tweaks to help your transient response, like a little extra timing around the transition between vacuum and boost, or whatever.

Hopefully, that explanation made sense - my basic point is try not to freak out over the complexity - start with something relatively simple, and work from there. To that end, I think that you are on the right path, as far as having resisted the temptation to 'fill in all the blanks', or trying to use someone else's calibration instead of trying to cal it yourself. Good luck, and I hope this helped. Also, feel free to e-mail me if you run into a jam.
 
1 - 2 of 2 Posts
Status
Not open for further replies.
Top