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Discussion Starter #21
Looks nice Dale!
What kind of spark plug gap are you going to use?
I think its around 30 thousandths which was recommended stock . Should it be different with a lot hotter spark ignition & increased compression with my rebuild .Combo cam,larger valves act?
 

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Mine was mounted on the radiator support but I had to move it due to the heat from the radiator and, I guess, the engine. It would run great until it got real hot during the summer months and would start missing. At one point, I had a "vapor lock" which had nothing to do with the Crane Ignition. After going through everything and scratching a bald spot on my head, I asked around and came to the conclusion that heat was bothering the ignition "box". I moved the "box" to the fender area and put some spacers underneath so air would circulate around it to help keep it cool. I haven't had a problem with it since and runs great!
Roy did you have to bring that thread back up again:aargh4:
http://www.opelgt.com/forums/group-6-engine/24969-backfiring.html
 

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Dale it was pure coincidence that we were both posting at the same time.

Sure open the sparkplug gap up with the high energy ignition system.
 

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I've got the XR700 and mounted it between the brake rod bracket and the inner fender where it can get circulation. I mounted the fireball coil in the original coil's spot, using the original bracket.

Dale, the set up looks very good. Love the way your engine compartment looks. Thanks for the photos.
 

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Let's see "If" I can shed a little bit of light on this.

You"ve now got this coil thats say's that it deliverers 60,000 volts.

The ignition system is very lazy in that it will only deliver the amount of voltage to fire the sparkplug.....and that's all!

The other key points is fuel mixture and spark timing.
Lean mixture takes more voltage as does more spark timing.
Ain't tuning fun?
 

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Discussion Starter #26
OK Dan so what your saying is it's going to take allot of trial & error in tuning to really take advantage of all that spark. Anyone with experience with this please chime in, we all can benefit. Carb is a 38 weber.
 

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I must be a little crazy.. I enjoy working on and trying to understand
what exactly is going on with ignition systems.
Believe it or not you can get a good idea of what's happening in the combustion chamber
just by looking at secondary.

Coil_current-secondary.JPG
The above is a great example of a poor running engine.
A good rule of thumb.
Burn voltage 2kv
Burn time 2ms
The red trace is showing that the fuel mixture is either very lean,bad fuel vaporization or over active egr flow.

Here is one that is a little better with the burn voltage.
The burn time is short @ only 1ms
DIS_Opel_idle.jpg
You need to see the sharp upswing at the end of the burn. It's telling that the spark was contained in the cylinder.
A direct result of increased pressure .
If at the end it slopes downward the spark is finding a ground outside of the cylinder.

After the mixture is burning well and the sparkplug has done it's thing.
It's nice to monitor the burn with a knock sensor.
I've got a flat response mounted on the block
http://delphi.com/shared/pdf/ppd/sensors/et_flat_knock.pdf..just haven't got to that point yet with the tuning.
The two wires under number two .
DIS install 2 - Opel Photo Gallery
 

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OK, but what gap should Dale and us others who have similiar engine mods be setting our spark plugs to? Please.

a. 30
b. 40
c. 60
d. other
 

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Discussion Starter #30
Yes this would be good to know. Put mine at 40 thousandths. Don't have the rotor without the resistor yet either. It'll be here wed. Question : with the stock rotor with the resistor how much does it reduce the spark too or does it reduce by so many volts?
 

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Sorry guys I can't say for sure.
I don't have a large enough database with the cih.
One GA. meet I might scope all the cars there and get a good idea.
So all that I can say is experiment with different spark plugs and gaps a see
what works for your cars.
Heck it can be a challenge just finding a good heat range.

I'm running a .050 gap long reach plug.
 

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OK, but what gap should Dale and us others who have similiar engine mods be setting our spark plugs to? Please.

a. 30
b. 40
c. 60
d. other
I always used .045" with my Jacob's ignitions.

When I ran the XR-3000 trigger with the PS92 coil and the HI-6R ignition box in our circle track car, we ran the open-face Torquemaster plugs. The distance from the center electrode to the perimeter was about .080". If you pulled a plug from the engine and cranked it over with the wire connected, those suckers would light up under the hood like Christmas lights...:yup:
 

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Did you notice a weak link with the solid rotor?
I've had those things blow holes and short out to the shaft.
The ignition rotor? I was still using normal resistor rotors back then.

I ran Jacobs ignitions from about '87 until '92 or so. Then I started experimenting with other systems...not that the Jacobs were bad, then never left me stranded or anything. But by then they had really started to climb in price.

Thanks. I'll start with a 0.040, then move to 0.045 on mine to see how it feels.
A good trick, at least on a dyno, was to start at a large gap. If it starts hard, or misfires at higher rpms, start closing up the gap until the problem goes away.
 
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Discussion Starter #36
Just a added note that I never knew about. The PS91 coil is quite noisy. It ticks quite loud with the rpm. I unknowingly put it on the sill in front of the drivers side of the gt. I'll try some rubber washers to cut it down. Might have to think about relocating it later. Really likeing the performance though especially with the "409" 1o.4 mm wires.
 

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News to me too, never had a noisy one before.
 

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I went with a crane 3000 ignition about three years ago. Works beautiful, never had an problems with turn the key and start her up. It's an optical set up, once you have that figured out (easy) you are ready to go. Never had any trouble with the original set up, no problems with the Pertronix, and no problem with the Crane 3000. all of them work well, if you don't want to spend the money on a Crane 3000, go with the Protinex. I have had nothing but success with all of them. Oh, also need to get the recommended coil that goes with the ignition choice.

Bob
 
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