Im going to install a tach in my truck hopefully today (85 f150 I6 etc...) and im just wondering whats the best way to go about it. Im probably just gonna get a cheapo autometer tach. I was going to check my haynes manual for any wires to tap into but i just wanted to know if there was an easier way.

 

I bought a cheapo one, and I tapped into the wire harness for the dash cluster. Using wiring tables from my Haynes manual, I was able to identify a (+) 12v, ground, tach signal, and interior light switched (+) 12v wire to splice (all four connections needed to run the tach!). It was pretty easy Check my gallery, I think I have pics of the process. If not I can add some
The hardest part was learning how to properly/easy remove the light control ****!

 

these jeep tachs work great for a 300.
JC Whitney part # ZX476802Y
0-6000 rpm

if you don't wind it out often this works great too
JC Whitney part # ZX133677X
0-4000 rpm

 

I had installed a Datcon one, 0 - 4000 RPM more accurated than 0 - 6000 for slow engines like 300's

 

If you cannot find a tach signal wire, the negative (-) side of your coil should work.

 

Yah lol mine go's to 8k rpm it's a little over what i rev you could say i guess. I think my dad forgot to take in to consideration it's not a built 302 seeing 7500 rpms non stop. More like a 1988 300-6 efi stock /w up to 4.5k or so max rpms lol.

 

4.5k!! holy I cringe when I get near 3k because it sounds like the world is coming to and end!

 

thanks guys i hooked it up last night. Runs great. I roughly hooked it up since i didnt have the time to find a proper place to find a power source and a ground. Going to finish it off tonight.

 

Where did you mount yours? I mounted mine on top of the dash LOL
It looks quite hot-rod-ish

 

i mounted it on the steering column. Im going to see how a like and maybe move it to the top of the dash later.

 

I didn't say i rev mine to 4,500 i just said redline is around there. Then again when i first test drove it i revved it to 5k not knowing what was under the hood at the time. It realy did sound like it was going to fall apart lol. Mine does see 3500 rpms though and often (only in 2nd gear) since i run a granny 4 spd which has the gaping hole between 2nd and 3rd gears.

 

Gerry, I hear you about that gap.

I have a NP 435 and the 3-4 gap is horrable. i shift to 4th at 20mph @2100RPM and when i get to 4th it is @ 1100RPM. I wish i had a Gear Vendor so i could split that shift and not have to run 65 at the redline.

I installed a factory tach. It works better in hot weather. and Intermitantly but i just took the printed circuit and tach and just swaped it out. Looks better than that dectative crap they put there.

DT

 

Wow i think that may even be a worse gap than my 2nd to 3rd. Mine usually drops from 2.5k rpms to about 1.25k shifting from 2nd to 3rd. I'd go drive it and tell you for sure but, it's the cleanest it's ever been and i'm avoiding driving because it's ready to sell that and i have the "un luck of the irish" stuff always brakes when i drive it lol. Not realy sure why either i'm not that mean to it and take very good care of it. I have about 3,000 in to it in repairs and such since i've bought it pretty easily i would expect.

 

Moreover, most 300's doesn't breath enought air over 2.900 unless some modifications..

 

I installed mine just in same place where the stock one comes inside cluster...