Tachometer 6 cylinder

[77K15]

Anybody make an in dash tachometer to replace the fuel gauge for six cylinder engines? 1977 K10 with the 292

 

[ali_c20]

Welcome. I've never seen a replacement tach for 6 cylinder engines, but maybe there are some out there.
You can use a tach signal converter, they are cheap and simply wire into the tach harness.

 

[Steelbuddha]

Seems to me a tach is a tach. Principle is the same whether you're measuring one cylinder or 12. Connect it properly, and it will work.

[*Edited to acknowledge that I am full of crap.]

 

[nvrenuf]

Seems to me a tach is a tach. Principle is the same whether you're measuring one cylinder or 12. Connect it properly, and it will work.

No, look at any aftermarket tach, there’s a switch for 4 / 6 / 8 cylinders.

 

[bucket]

No, look at any aftermarket tach, there’s a switch for 4 / 6 / 8 cylinders.

Or on some old ones, a wire you cut.

 

[bucket]

Seems to me a tach is a tach. Principle is the same whether you're measuring one cylinder or 12. Connect it properly, and it will work.

It will work, but not read the correct RPM. I personally do not know how, but folks that are smart with electronics can convert the signal for the proper reading.

 

[Steelbuddha]

No, look at any aftermarket tach, there’s a switch for 4 / 6 / 8 cylinders.

Correct. That's kinda what I meant, however poorly worded.

 

[Gander]

Anybody make an in dash tachometer to replace the fuel gauge for six cylinder engines? 1977 K10 with the 292

There’s a guy in Louisiana that makes repro boards to repair the factory tachs in 80s Camaros/Firebirds/Trucks/Vettes/etc. I used his board to fix the factory tach in the cluster I built for my truck. It was around $60. He includes a potentiometer soldered to the board so you can dial in the rpm yourself to get it correct. For me, with a lockup torque converter/3.73 gears/31” tires, I know that at 70mph I’m turning around 2kRPM so when I got the tach board installed I just ran a few passes on the freeway, pulling off to adjust with a small screwdriver until I had it right. Cajun Tach Shop is the name of the business. Sells on his website and also eBay. He might could build one that would read pretty close for a 6 cyl or just buy the same board I did and dial it in yourself. Wouldn’t even need to mess with running on the freeway and pulling off to adjust if you’ve got a timing light that’ll also show you rpm, could dial it in in your driveway if you’ve got that.

Just checked and it says on his site that he can set up a truck tach board for you for 6cyl. Just let him know when you order that it’s for a 6cyl.

GM, Chevy Truck, C2500, K30, C30, C10 Tachometer Circuit Board | Cajun Tach Shop

This is a new, easy to install, direct replacement circuit board.Pre-Calibrated for V8Lifetime Warranty, no hassle returns. Easy InstallationFast & Free Shipping. Same day shipping if ordered before 11:00am. This is a new, direct replacement circuit board designed to fit GM trucks. Please...

www.cajuntachshop.com

 

[Turbo4whl]

Some medium duty square body trucks with 6 cylinder diesel engines would have a 0-4000 RPM tach.

Signal generator installed in a fuel injector line.

You must be registered for see images attach

0-4000 RPM tach

Seems to me a tach is a tach. Principle is the same whether you're measuring one cylinder or 12. Connect it properly, and it will work.

No, the tachometer RPM = rotations per minute. Every engine rotation on a 4 stroke V8 engine fires 4 times. 6 cylinder 4 stroke fires 3 times every rotation. Need two full engine rotations to fire all cylinders one time.

 

[Turbo4whl]

More info:

CLICK HERE

 

[Gander]

More info:

CLICK HERE

A lot of that info is good but some of it is bad. It states in there that you can’t run a factory tach ‘87-‘91 because of the VSS/ECM/etc on TBI trucks and that’s just not true. The white wire running off the coil on the TBI trucks is a tach signal wire and it works just fine with the GM tach in my 1987 5.7 TBI truck with a VSS on the back of the speedo for Cruise Control and for the ECM.

 

[Turbo4whl]

A lot of that info is good but some of it is bad. It states in there that you can’t run a factory tach ‘87-‘91 because of the VSS/ECM/etc on TBI trucks and that’s just not true. The white wire running off the coil on the TBI trucks is a tach signal wire and it works just fine with the GM tach in my 1987 5.7 TBI truck with a VSS on the back of the speedo for Cruise Control and for the ECM.

Yes, like anything from the internet can be wrong, the pictures linked show the gauge faces from the different years. That might be useful for someone trying to match what they have.

 

[Gander]

Yes, like anything from the internet can be wrong, the pictures linked show the gauge faces from the different years. That might be useful for someone trying to match what they have.

Agreed. I wish I’d have taken a pic of the 1985 cluster I bought for parts just to have it up there because there were slight differences. The redline marker on my 1985 tach is white, the 1980 Canadian cluster pictured on that site is yellow/red. I’ve never seen a 1980&up repro tach with a redline marker. The 79&down repro ones have it. There’s differences in the markings on the fuel gauges too, large and small. ‘87&up they use full/half/empty circle markings, prior to that it’s E/F isn’t it?

I also wish they had pics of the backs of the clusters because that’s why I think they say that you can’t have VSS and the tach. The tach cluster back on the 85 cluster I bought had an opening for the speedometer in the rear that was too small to allow for the plug into the back of the speedometer for the VSS. The ‘85 Speedo I got had the window on the back of it for VSS and an untapped hole for the screw to secure the VSS plug but the ‘85 tach cluster back speedo opening was too small to accommodate the ‘85 speedo if a VSS was connected without trimming the cluster back to clear it. Also, the 1987&up speedometers have a larger back than previous years so neither my original ‘87 speedo or the NOS ‘88 speedo w/trip odo I bought to replace it would fit the 1985 tach cluster back without trimming material off the cluster back with a dremel. The tach cluster backs that most of the places like LMC/USA1/etc sell these days look like they’re set up for the ‘87&up speedos which means that all the earlier ones will fit too. Anyway, I just had to remove the speedo cable clip from the 85 cluster because on that cluster it screwed to the cluster back, then trim the 1985 tach cluster back to fit the ‘87&up speedo, and use the ‘87&up speedo cable clip because on the ‘87&up speedos the speedo clip is screwed to the back of the speedo itself.

 

[Dejure]

Had a long post about my tach install, then it dawned on me, you're dealing with the stock dash components and the limited room that comes with that, versus the entire dash I built (mahogany) and was able to modify to do everything I demanded of it.

No reasonable way to install most aftermarket tacs without destroying your circuit paths, for example, a Bosch tac that will run on a 4, 6 or 8, because it's about 5" too deep.