Need a "simple" answer about tachs...
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,993
Likes: 9
From: Gig Harbor WA
Need a "simple" answer about tachs...
Bought ZZ4 engine, it came with HEI distributor, I know I need EITHER a tach drive distributor OR convert (change?) my existing tach to electronic. Since I have a NEW HEI on top of the ZZ4 , and cant see buying ANOTHER HEI dizzy with tach drive.......
Here comes the question....to "convert" my tach to electronic, really means source an electronic tach from a later model Vette????
Or...am I missing something here? Can't physically "convert" my existing mechanical tach to electronic, right?
Did search, and I THINK I came up with..I have to get a whole 'nother tach, electronic style...
I have read that electronic tachs are a nice upgrade. I'm not too concerned with originality here.
Thanks!!
Here comes the question....to "convert" my tach to electronic, really means source an electronic tach from a later model Vette????
Or...am I missing something here? Can't physically "convert" my existing mechanical tach to electronic, right?
Did search, and I THINK I came up with..I have to get a whole 'nother tach, electronic style...
I have read that electronic tachs are a nice upgrade. I'm not too concerned with originality here.
Thanks!!
Racer
Joined: Jun 2006
Posts: 316
Likes: 1
From: Southern California
I can't give you the details, but I think both options are available.
I was in the same position as you needing to either replace the HEI non mechanical or replace the tach.
I opted to replace my 73 tach with a 75. That simple. You just need to run the hot, ground and lead to the tach.
But during my research I did read where you can actually convert you tach with parts from some other readily available tach on the market. Sorta gutting the new on eto place the parts in yours. Sound like too much work for me.
I was in the same position as you needing to either replace the HEI non mechanical or replace the tach.
I opted to replace my 73 tach with a 75. That simple. You just need to run the hot, ground and lead to the tach.
But during my research I did read where you can actually convert you tach with parts from some other readily available tach on the market. Sorta gutting the new on eto place the parts in yours. Sound like too much work for me.
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,993
Likes: 9
From: Gig Harbor WA
Melting Slicks
Joined: Mar 2006
Posts: 3,342
Likes: 7
From: Connecticut
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,993
Likes: 9
From: Gig Harbor WA
Melting Slicks
Joined: Mar 2006
Posts: 3,342
Likes: 7
From: Connecticut
Yes, I bought the long block because I didn't see any reason to pay for parts I already have and do unnecessary conversions.
I don't see any reason that my tach drive wont run a 10.1:1 engine. GM did it for ages on points.
I also despise going behind the dash so thats not an option for me.
I don't see any reason that my tach drive wont run a 10.1:1 engine. GM did it for ages on points.
I also despise going behind the dash so thats not an option for me.
Team Owner
Joined: Jul 1999
Posts: 65,492
Likes: 230
From: Orange Park Florida
Tach from 75-77 will work fine....it's the route I would use....
you can get your old monster rebuilt electronic, but it's expensive and takes time....just easier to git er dun in one morning.....
no way would I consider running a mechanical tach...total junk IMO....
you can get your old monster rebuilt electronic, but it's expensive and takes time....just easier to git er dun in one morning.....
no way would I consider running a mechanical tach...total junk IMO....
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Tech Contributor
Joined: Jun 2004
Posts: 20,905
Likes: 962
From: I tend to be leery of any guy who doesn't own a chainsaw or a handgun.
I've converted several points distributors over the years to use an HEI module. My '69, along with my buddy's '72, retain the stock tach drive distributor. I just installed a variable reluctance sensor in it, and hooked it up to a reliable, and inexpensive, HEI module under the shielding. Works great, and stone reliable.
Thread Starter
Safety Car
Joined: Oct 2006
Posts: 3,993
Likes: 9
From: Gig Harbor WA