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Tach with G3 hemi?

Tomcat

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Is anyone running a stock style in dash tach with a G3 swap? If so, how is that done? The only controller I’ve seen that specifies it has a tach wire is Edelbrock, but I can’t verify that it would drive an OEM style tach???? I am planning to retain a completely stock appearance with my car......just that beastly 392 under the hood!
 
Well I had tried to search this topic before, but I didn’t understand how to search within a specific forum....I finally figured it out and now have some base knowledge to work with.
 
I am surprised no one answered. I didn't because I am not 100% of the information, however stock tach's work off a coil signal which the modern engines I do not believe provide at least in the same manner as the tach was designed for. Therefore you need an adapter like one from MSD I think.

Call or contact Holley (they might have a chat function on their website) and ask them. They have done a lot of G3 Hemi conversion stuff and I suspect this is one thing they have encountered.
 
I am surprised no one answered. I didn't because I am not 100% of the information, however stock tach's work off a coil signal which the modern engines I do not believe provide at least in the same manner as the tach was designed for. Therefore you need an adapter like one from MSD I think.

Call or contact Holley (they might have a chat function on their website) and ask them. They have done a lot of G3 Hemi conversion stuff and I suspect this is one thing they have encountered.
I did manage to find some discussions here on the subject, and found where some had managed to do it with an adapter as you suggested. I’m still trying to educate myself further on which controller to buy, but have found for certain that both Mopar and the Edelbrock have a tach signal wire to work with .....still not certain about the Holley, but I plan to make some calls as soon as I can take the time to do so.
 
I have a built 392 whippled that I run a newer style tach. The tach runs off a msd signal wire to a dakota digital. Works great! Not sure how to go about using the stock tach. Sorry
 
I’ve been told by Classic Instruments that they are going to introduce a solution for this problem at SEMA this fall.
I’ve been told from a guy that restores our clusters that the MSD adapter really doesn’t work.
 
I’ve been told by Classic Instruments that they are going to introduce a solution for this problem at SEMA this fall.
I’ve been told from a guy that restores our clusters that the MSD adapter really doesn’t work.
I am using one of the MSD adapters in my 70 Challenger RT with the stock Rally cluster and it works fine.
 
I am using one of the MSD adapters in my 70 Challenger RT with the stock Rally cluster and it works fine.
I bought the MSD adapter for my RR but didn’t try it yet. A guy who restores clusters told me it wouldn’t work. I guess I know what I’ll be doing soon.
 
I'm glad to get a testimony from someone here about it. I felt pretty certain it would work since it essentially does the exact same thing the factory tach feed from the coil does.
 
What engine controlling system are you using? If you are using a Holley product (terminator X, etc.) there is a specific wire/lead for your tach that is in the main harness, I think it is a blue wire and provides a square wave signal.
 
What engine controlling system are you using? If you are using a Holley product (terminator X, etc.) there is a specific wire/lead for your tach that is in the main harness, I think it is a blue wire and provides a square wave signal.
I still haven't decided for certain yet. I was hemorrhaging money for so long on the body work and paint that I haven't proceeded into acquiring the ignition system yet, but I hope to get on that in the near future so I can get it all installed and running by next summer. At the moment, I'm thinking I'll likely use the Mopar kit though.
 
I still haven't decided for certain yet. I was hemorrhaging money for so long on the body work and paint that I haven't proceeded into acquiring the ignition system yet, but I hope to get on that in the near future so I can get it all installed and running by next summer. At the moment, I'm thinking I'll likely use the Mopar kit though.
Well for what it is worth, I did the research when I was planning my 71 build (crate 5.7) and decided and am using a Holley Terminator X Max harness and ECU. The main reason/s I decided this were;

1. I am familiar with the Holley software (I have a HP system in my 70 Challenger)
2. the Holley system is very tunable whereas the Mopar one is not nearly as configurable
3. the Holley system will "learn" on its own as does the Mopar system
4. I felt that the Holley system provided many more options (VVT, DRW, various dashes, etc.)
5. Holley has a lot of tech and available resources for when things dont work right, I do not think you will find the same with Mopar.

Regardless and as it relates to the tach issue, I think either or any system will provide a square wave signal wire that can be made to run a tach either with an adapter or directly. Lastly you can always have your tach "upgraded" via one of the instrument cluster repair places (I think you can just buy the new style tach and install it).

Here is a link to site I just found that might be helpful: https://newvintageusallc.mybigcomme... operate by reading a,of times the coil fires.
 
Well for what it is worth, I did the research when I was planning my 71 build (crate 5.7) and decided and am using a Holley Terminator X Max harness and ECU. The main reason/s I decided this were;

1. I am familiar with the Holley software (I have a HP system in my 70 Challenger)
2. the Holley system is very tunable whereas the Mopar one is not nearly as configurable
3. the Holley system will "learn" on its own as does the Mopar system
4. I felt that the Holley system provided many more options (VVT, DRW, various dashes, etc.)
5. Holley has a lot of tech and available resources for when things dont work right, I do not think you will find the same with Mopar.

Regardless and as it relates to the tach issue, I think either or any system will provide a square wave signal wire that can be made to run a tach either with an adapter or directly. Lastly you can always have your tach "upgraded" via one of the instrument cluster repair places (I think you can just buy the new style tach and install it).

Here is a link to site I just found that might be helpful: https://newvintageusallc.mybigcommerce.com/blog/tachs-tachs-and-more-tachs/#:~:text=Tachometers operate by reading a,of times the coil fires.
Cool....I appreciate the link. I have a buddy who drag races and he's worked on me pretty good about going with the Holley system, and he's familiar with them and could help me with it. He's a hard core Pontiac man, but ignition is ignition, so I may well go that route too.
 
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