1970 Chevelle SS454 LS5 Convertible

[XXXGoldL34M20]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: YENKO DEUCE REGISTRY</div><div class="ubbcode-body"> [img]<<GRAEMLIN_URL>>/Can-I-Have-It.gif[/img] </div></div>
I wish I had a spare but that one is on my motor. [img]<<GRAEMLIN_URL>>/naughty.gif[/img]

[XXXGoldL34M20]

Notice the strange incorrect Tach that is a 5000 redline setting, should be a 5500 red line Tach For the Big Block LS5 but this is not first time I have seen Chevrolet incorrectly install a Tachometer in a Big Block car with a small block Tach. You could order this gauge package for a Malibu and get the 5000 red line tach so it did happen a few times that Chevrolet made a mistake with the tach.

[67 Nova Boy]

Thanks..if only I can remember where I put it! My wife moves stuff and it takes me years to find it! [img]<<GRAEMLIN_URL>>/biggthumpup.gif[/img]

Dave
67 Nova Boy

[XXXGoldL34M20]

Just realized that box 72 &quot;Tach&quot; on the build sheet has 938 which is the 5000 Red line Tach, I usually see this on Atlanta built cars but interesting to see one on a Baltimore built LS5. [img]<<GRAEMLIN_URL>>/biggthumpup.gif[/img]

Here is the breakdown on the box 72 &quot;Tach&quot; on a 1970 Chevelle build sheet. 935=5000 Red line, 983=5500 Red Line and 985=6500 Red Line.

[USA1]

It's it supposed to be yellow first and then the orange/red on the tach? Why is it orange/red then yellow..?

[XXXGoldL34M20]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: USA1</div><div class="ubbcode-body">It's it supposed to be yellow first and then the orange/red on the tach? Why is it orange/red then yellow..? </div></div>

Good eye and question?
Here is a photo of an original 5000 red line tach and 5500 red line tach and one taken from my original LS6 with the 6500 red line.

They all show the yellow first than red/orange

[markinnaples]

To me it looks like it's all orange in that section, it's just the sunlight hitting the higher RPM section and the shadow of the steering wheel making the lower RPM orange part look darker?

[Bill Pritchard]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: markinnaples</div><div class="ubbcode-body">To me it looks like it's all orange in that section, it's just the sunlight hitting the higher RPM section and the shadow of the steering wheel making the lower RPM orange part look darker?
</div></div>

What he said. [img]<<GRAEMLIN_URL>>/headbang.gif[/img]

[Tracker1]

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Bill Pritchard</div><div class="ubbcode-body"><div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: markinnaples</div><div class="ubbcode-body">To me it looks like it's all orange in that section, it's just the sunlight hitting the higher RPM section and the shadow of the steering wheel making the lower RPM orange part look darker?
</div></div>

What he said. [img]<<GRAEMLIN_URL>>/headbang.gif[/img] </div></div>

Agreed, just the light playing tricks.

[SS4Real]

Here's a correct summary of 1970 Chevelle SS Tach's. Ultimately, you must look at the car's original build sheet to verify which tach came in the car (not all SS Chevelles came with a tach but all SS Chevelles had the round dash pods). You begin by looking at box 107 of the build sheet to see if the car came with the U14 IP Gauges option. If it does have the U14 IP Gauges option, then your next step is to look at box 72 to see the code for the tach in your car (if your car does not have the UP14 IP Gauges, then you will have --- in box 72 which means no tach). After looking at the code in box 72, here is the breakdown of the tachs that came in the 1970 SS Chevelles:

L34 396/350 hp 5500 rpm tach code 985
L78 396/375 hp 6500 rpm tach code 983
LS5 454/360 hp 5000 rpm tach code 938 ****or****
LS5 454/360 hp 5500 rpm tach code 985
LS6 454/450 hp 6500 rpm tach code 983

It's also possible that some cars **may** have come with different tachs due to different assembly plants or parts shortages. Again, ultimately to prove that exception you would need an original build sheet to see what code is in box 72.

Atlanta built LS5's commonly came with the 938 5000 RPM tach and some Baltimore built LS5's did as well. Again, you have to check the code in the build sheet (if available) to verify.