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I've found that I'm driving my '49 GMC 3/4 to work quite often and I get up on to the freeway to get to work. Amazing how many people I [censored] off by slowing their day down to 50. Oh well, the kids all wave! I'm a little worried what RPM the original 228 is turning. Has anyone installed a tach in their truck and if so can you outline the steps and type of tach you would recommend. The truck has been converted to 12 volt.
Thanks
Murph

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1949 GMC 3/4 ton

If another SUV driver flips me off!... I love L.A.

Most any aftermarket tachometer from the local auto parts store will do the job. I would suspect your engine is turning about 3500-3800 rpms at 50 mph, which is plenty. Part of that is due to the 4:56 gears in the rearend. But just remember, when those SUV people flip you off on their way buy, they are telling you....you are still number one!! You also need to remind them that your truck was here first and you could build a whole darn SUV out of the metal contained in just your front bumper !! If they get too fisty.... challange them to a 20 mph head-on. Then you will see who is laughing.....Randy

Kmurph,
Since my speedo hasn't worked for years, I installed a tach just a week ago in my '50
chevy (12 volts). Went to a local Pep Boys store and bought the smallest tach (2-1/4" dia) I could find (Brand name of Actron). Had it installed in 30 minutes.
4 wires (Ground, hot after switch is on, light & neg side of coil).
I've always wanted to know the RPM's and now I know. Had my wife follow me to tell me how fast I was going and I noted the rpm's. As soon as I can confirm what gears I
have in my rearend, I can then calculate the different speeds per different rpm.
My 235 seems to run its best at just over 2,000 rpm. I'm gun shy to take it beyond 2,500.

Thanks fifthave and cmayna.

Murph
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...(O)...............(O)

'49 GMC 3/4