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Tachometer problems

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Old 05-05-2003, 12:04 AM
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Turtle
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Default Tachometer problems

I have a question. The tachometer on my 84' GT is not currently working. But there is a catch. The car is no longer EFI. It is now carburated and has a MSD 6AL ignition system. The tach is the stock one. I looked up what to do when this problem occurs on the MSD site. It says that I need an adapter. I was wondering if anyone out there has had the same problem. It seems like it should be an easy fix, but nothing has been simple on this car so far. If anyone has any ideas I'd love to hearthem. Thanks.
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Old 05-05-2003, 02:22 AM
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302forever
 
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Default Tachometer problems

On most tachs the signal line goes to the low side of the coil, the one that goes to your ignition module. I've never looked to see how they do it on EFI, if the computer does it or if it still goes to the coil.

I'm curious as to why you went to a carb. I will never be an EFI fan, my carbureted vehicles start and run much better than the injected ones. I think fuel injection is a sales gimmick. They can only charge so much for a carb. They can charge A LOT more for EFI.
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Old 05-05-2003, 02:35 AM
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jeep45238
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Default Tachometer problems

EFI can adjust itself (to a reasonable limit), gives more power, and better gas milage.



Sorry, but carbs are dead. The Chevelle used to make about 1100 or so horses when we switched it to blown and alcohol, via a carb. Gained 200 when we went EFI. That same system lasted to damned near 2000 horses and well over 2000 ft. lbs.
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Old 05-05-2003, 12:26 PM
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Turtle
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Default Tachometer problems

I guess I am not really good at the EFI stuff. For some reason I don't like the computer (and the feeling is quite mutual) on the EFI. Carbs just make sense to me. Don't get me wrong, I think that overall, EFI is better. They would have stayed with carbs if EFI didn't work. But, I still love the look of an Edelbrock with cowl induction. I feel it is easier to work on a carbed engine. I don't race, but I do like to go fast. This car has plenty of punch forwhat it is.
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Old 05-05-2003, 11:16 PM
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lloydchristmas
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Default Tachometer problems

Dont mock what you dont understand. Ask questions and learn something. If you need to mock something lets make fun of MOPARs LOL
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Old 05-06-2003, 03:14 AM
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Default Tachometer problems

I think if EFI was better, we'd see it in NASCAR. Those boys stay with carbs. because they are much more reliable, produce better throttle response, and of course are much easier to repair. The thing that people always forget about carbs. is, mother nature makes the adjustments. Everything is automatic with the Venturi principle, and mother nature doesn't have to wait for a computer to tell her what to do. I have 5 vehicles with EFI and 3 with carbs. All I know is when I twist the key on the carbs they fire off instantly, and when I crack the throttle, they go. Can't say the same for the EFI.
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Old 05-06-2003, 10:37 PM
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Turtle
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Default Tachometer problems

I agree. I don't like the idea of having to rely on a computer to run the car. Being a mechanical system is more reliable. Mind you, this is only my opinion. Through my experiences working on my personal vehicles, I have found the carbed ones much easier to fix. But, I don't know very much about EFI except the basic principal. I am still curious, now that it is carbed with a MSD ignition, is there any way to hook up my tach without the $60-70 adapter (with the stock tach)from MSD?
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Old 05-06-2003, 11:33 PM
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makarovboy
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Default Tachometer problems

The people in NASCAR run on Rules. You can bet when they get away from restrictor plates and carb sizes, depending on the track, you will see EFI with injector changes, TB's, etc. EFI developes more power, better mileage, and, like it or not (I don't), less emissions. Believe me, if you ever have to take apart and screw around with a carb, it's every bit as complicated as EFI. Take your carb to altitude and see how it runs. A computer will automatically adjust for this. Just one example. Computers and EFI will only get better, but if it quacks like a duck, and looks like a duck, it's still a carb.
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Old 05-06-2003, 11:48 PM
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Default Tachometer problems

If the tach is self contained, not controlled by the computer, you should be able to simply connect the sample line to the low side of the coil. The side that is connected to the ignition module. On most of the tachs I've seen, that is a green wire. I don't know if that is an industry standard. Do you know where that wire might be or is it just lost in a harness somewhere since the computer was removed?
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Old 05-07-2003, 10:14 PM
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Default Tachometer problems

carbs can be tuned to YOUR likeing very easy...no electic crap to fail...and trouble shooting a carbed engine is a snap...
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