Hole in the hood or hole in the head?
 

I'm curious as to how the 68/69 crew feels about cutting that big hole in a good hood for a hood tach.
Now, I know that the standard answer that always comes back is- "It's your car, do what you like" and there's nothing wrong with that answer except that that is not the question. How do you feel about it?

It’ll make your GTO even cooler. Cut the hole!

I never once have regretted it!

My in-dash tach took a dump quite a few years ago and I really miss having a tachometer in just about any kind of car, but especially this one. Even though I wasn't actively shopping for one I ran across a pretty good deal on a hood-tach and bought it. Then the doubt started creeping in....
I just finished wiring it under the hood to see if it worked and it's perfect. Then I come back here and see these replies and I'm getting a little stoked... I guess a hole saw is in my future!

Greg Reid my only input to this is...... post up some pics when she's done !!

She'll be even lighter!

Haha, will do HO LEMANS!
The biggest challenge for me will be getting it painted without too much orange peel. Being a relatively small job I'm considering using an airbrush. Gotta play around with some test panels.

Use a punch out tool easier and cleaner

I've used them before but don't have one. I'll bet a good three and a half inch one is pretty expensive. Also, the placement of the hole has it coming through a fair bit of the bracing. Will a punch out tool stay straight going through the multiple layers on one side of the hole only?

Just get the Hood Tach 1st, then cut the hood. And perhaps a Dash Clock. You are gonna want that.

Well, I have the hood tach already and yeah, at some point I'll replace the blown dash tach with a clock. I'm in no hurry to pull the instrument panel though.
I wired the underhood harness today so l'm committed to doing it. When I get it painted to my satisfaction I'll cut the hole.

I used to be able to remove/swap the Dash Clock ( or Dash Tach ) by using a 1/4" nut Driver, without removing any Dash stuff.

Certainly remove the Lower AC vent system if it were there.

My last effort with installing the Dash Tach was tedious to do such. Think i removed DashPad to properly R&R the 2 upper 1/4" screws.

Do it. Too cool not to.

Go for it…no regrets adding one to mine. Here’s a few pics of my install. Mine wasn’t as nerve racking since my hood still needs painting.

Thanks kk68. Those pics are helpful. I'm using the template provided with the tach and it puts the center of the hole 13" from the back edge of the hood. 3/8" closer than yours and I guess that's close enough but it looks to me that you barely had to touch that hood bracing when you cut your hole. Mine appears to be taking quite a lot more from just eyeballing it. That's a concern because I don't want to have to cut through any more of that bracing than I have to.
In fact, as close as I can tell, the front edge of that bracing is going to wind up almost at the center line of my 3.75" hole! Right about where the threaded studs are. I think I need to move it up 3/8 to 1/2" to be closer to where you are.
Also, that 2* offset isn't mentioned. If anything, looking at my pattern it seems to be offset about the same amount but in the opposite direction.
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I did a lot of research on locating the proper size and spot for the hole and settled on the location from prior post. This is an old photo I found that showed the factory location from the underside of the hood with minimal cut into the bracing…very close to where I ended up.

The Hood tach is worth it and just make sure you use the correct Template and put the hole in the correct place.

I'm comfortable with the location now... I moved my pattern forward about half an inch and looked at it carefully from the side with one of those little antenna magnets stuck to the front edge of the brace. That gave me a visual marker from the side where I could see my pattern and the little antenna hanging down from the bottom of the hood at the same time.
I think it's going to wind up in just about the same place as that photo you just posted.
I'm definitely not cutting anything until I can get the paint right. I don't want it to look like an add-on, but like it was painted with the car.

I've always wanted to add a tach to the hood of my 71 LeMans, but cringe every time I look at my perfect original hood. A guy up the street did it to his 72 and it looks great. I guess a good look under his hood to see what he cut into is my next project. Anyone else do theirs? GREAT THREAD!!

For an earlier car, I lean slightly towards NO. Not only is the 67's tach much taller, but there's also the body lines. But the 68-70s are curvy, and the tach is "short". It really is an iconic look. I'd be hard pressed to fault anyone for adding it. :thumbup:

Exception: truly historic cars. As documented, or it's wrong. :rant:

On the earlier models...I don't hate the hood tach on them but I agree on both points that you made. They look better on the 68 and later A bodies and also look good on the first gen Firebirds.

One of my favorite additions to my car. No regrets at all. Do it!

Fortunately I saved the quart of single stage paint from 2011 back when I was thinking of trying to paint my own car. All I can say is that now I understand why experienced painters don't want to use single stage for metallics. This was my second try after having to quickly wipe down the first try with lacquer thinner and respray. Had some serious tiger stripes and a couple of big sags.
I'm really happy with the amount of gloss for a single stage paint. I have very little experience with spraying paint. I mostly limit myself to primer and body work.
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I think that the color is going to be close enough for me although I think, and again I'm not experienced at this but I think that one mistake I made was not agitating the paint enough before I poured it in my sprayer. The bottle that I poured it from had a lot of silver in the bottom of it at the end of the job.
It's really, really close to my paint but I think the lack of silver gives it a slightly darker hue.
Easy enough to repaint later if I can't live with it but I think it's going to be okay.https://uploads.tapatalk-cdn.com/202...8c3e175f0f.jpghttps://uploads.tapatalk-cdn.com/202...d29f2354b1.jpg

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I actually did fudge it forward 3/4". I'm just going to cut through the sheet metal and then determine what I'll do about the cross brace. It's going to be a pretty small half moon. If it feels like the sheet metal is holding the hole saw straight enough without bucking or anything I'll just continue through it.
Nice suggestion about the tin snips but I'm already committed to the hole saw at this point having already purchased. By the way kk68, I got the holesaw you posted. it.https://uploads.tapatalk-cdn.com/202...937d13449d.jpg

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I don't understand why you claim the brace is in the way......I've done a couple of them and used the supplied
template and the brace was not in the way at all, no brace cutting required.

I just cut mine today. If you look at the photo in post #17, mine wound up exactly where that one is. It took a half moon piece of the brace about 3/8" deep at the apex. I could have moved it forward and avoided it altogether but I decided to go with the template that came with the tach.
I have no explanation for the discrepancy between your template and mine.

One thing I do not understand is why the Ames version only has two studs at the rear/center and nothing on the front. As soon as I tighten those two nuts down, the front edge kicks up. That's not going to work for me. Looks like a J. C. Whitney add-on. The factory added a rivet, they say for theft protection but I wonder if it wasn't because of complaints about the appearance.
Has anyone needed to add a rivet or stud near the front edge to make it conform to the hood better? I'm doing one or the other today.

The hood is not irreplaceable. You can always buy a new one if you later change your mind. Or, buy a new one now and put your hole in that one.

Oh, it's a done deal now Goatracer. Already mounted. I took it back off to epoxy prime the bare metal around the holes. I also added a threaded stud to the front. Now it fits close to the hood as it should with no big gap at the front.
Pics later.

Greg:

Paint job on the tach looks great. Mine sits flush and I did not need to add the front rivet. Did you use a rubber gasket between hood and tach? I think they are sold separately by Ames.

KK

My problem turned out to be a combination of thick silicone sealant and needing a front attachment point. I 'shaved' the silicone flat with the edge of the base using a fresh razor and tapped a 10-32 hole in the plastic at the front...then drilled one more hole in the hood.
Here are the pics. Oh well, nothing a good tig man can't fix!
I gotta tell you, I wasn't happy about it with those gaps. I almost went into regret mode...but I'm happy with it now. Also, it works great!
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Greg that looks great, a nice addition to an already beautiful car!

Thanks HO LEMANS!

Looks good, super clean cut on the hood. Looks like a good match on the paint. Nicely done!

Thanks Ken...I think we need to find a market for lightly used 4" hole saws. $35 and I'll probably never use it again.

LOL - I've got one lightly used 4" hole saw as well. Need to find some more stuff to cut some 4" holes in or maybe start a 4" hole saw rental business.

You ended up with a perfect result, $35 well spent in my opinion.

Nicely done, only comment for others who might read this is to be careful that the starter bit is a correct bit for a hole saw. Seen guys use a regular drill bit without the long shank so that as the hole saw starts cutting the starter bit is still cutting the starter hole wider because there is cutting surface there instead of a smooth round shank. Next thing you know your 4" hole saw just made a 4 1/2" inch hole.

Ouch... that'll ruin your day!