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Tach is really slow...why?

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Old Feb 22, 2006 | 12:25 PM
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Default Tach is really slow...why?

I have a 5" tach installed and it is so slow. I have to set my redline at like 4500 just so the light goes off around the redline. Its a pain in the ***. Is there any way to fix this or is it just the way it is?
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Old Feb 22, 2006 | 02:15 PM
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Sounds like it is set for a v8. If I'm not mistaken you have to set an aftermarket tach for a 4 cyl. There is usually a switch, or sometimes you have to cut a jumper wire or two. What tach do you have?
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Old Feb 22, 2006 | 02:29 PM
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Nope is set for a 4 cylinder. Its a Type R carbon fiber 5" tach.
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Old Feb 22, 2006 | 02:45 PM
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Its probably something with the tach itself, and not a car issue. Shift lights always indicate properly.

Hey, who's got an electronic tach out there?
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Old Feb 22, 2006 | 02:52 PM
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So when you say shiflight, you mean 1 seperate from your tach. I thought you had a tach with a shiftlight. Does your factory tach still function? I would try different #'s of cylinders and see if it changes based on your factory tach. Did it work properly before, or has it been this way since install? Sounds like the tach may be bad. Where do you have it connected for the rpm signal?
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Old Feb 22, 2006 | 06:16 PM
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Its been like this since the install. It is a tach with a shift light. Yes my factory tach still functions and is perfect speed. When I change different cylinder settings it messes up types of RPMs available. Like if I set it on 8 it will only let me set it no less than 4000 RPM. I hope its not a problem with the tach. I heard that LS1 tach signals are slow. Could this be a reason or does everybody else's tach work fine?
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Old Feb 22, 2006 | 09:34 PM
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Changing the setting on the tach doesn't help? Is the shift light the only thing that doesn't work right, or the tach doesn't read correct either? Not sure I understand. If you set the redline to 4500, does the light come on at 4500 or at your actual redline on the factory tach?
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Old Feb 23, 2006 | 12:11 AM
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No no... the tach reading is really slow. The light goes on at whatever rpm i set it to go off on the tach. But if i set it at 5900 like i would like to, under hard acceleration it wouldnt go off until around 6800. The needle is really slow if that helps at all. Picture accelerating and your rpm is at 5000 on your factory tach. Well on the aftermarket tach, It will only be at 4000. Hope this helps...
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Old Feb 23, 2006 | 12:24 AM
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Well, the stock tach is slow too. My 6k shift light comes on at 5.6-5.7k rpm indicated on the stock tach. Key is getting a separate shift light so you can get a no-bullshit reading.
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Old Feb 23, 2006 | 06:32 AM
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Yeah I prolly shoulda thought about that. So there is nothing I can do with it now, just deal with it?
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Old Feb 23, 2006 | 06:57 AM
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Ok. I think I got you. If you set the light to 5900 it comes on at 5900 on the new tach, but actual 6800 according to the factory tach? There is something wrong. How do you have it wired? It may also be that this particular tach can't recognize the ls1 tach signal. You should be able to speed it up by changing the setting on the tach to a lower number of cylinders.
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Old Feb 23, 2006 | 01:46 PM
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nope you got it backwards...
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Old Feb 23, 2006 | 11:00 PM
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Damn, I'm sooo confused!

Ok. We are talking about the light in the aftermarket tach right? When you set it to 5900 it comes on at 5900 according to the factory tach, but at 6800 according to the aftermarket tach? If the factory tach reads 5900 the aftermarket reads 6800? That sounds like the aftermarket is actually too fast.

I can say that if the light in the aftermarket tach works right, but the tach itself doesn't. You have a bad tach.

In the immortal words of Jerry Mcguire, "Help me, help you."

Damn I'm confused!
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