FYI: TACH DASHES. (factory)

[too much stuff]

OK, it is cold outside so i figured i would do another FYI. Every so often you hear of the 4,000 rpm 6 cyl tach dash. I have never seen one and believe they do NOT exist. The 4,000 rpm tach dashes would be a mechanical drive (like a speedo hook up) and probably has a redline. (diesel) I have seen 6 cyl dashes with the 5,000 rpms which is identical to the V-8s. Only difference is the stamp on the back. (last pic)
The diesel tachs have a needle like a speedometer also. I included 2 diesel pics to show different redlines which i assume would be for different engines. If anyone can add info, or has questions...
Enjoy, Eric

[tcb-1]

very nice info, Eric!

[69sixpackbee]

Kewl......can I have one??

[Brad]

Those 4,000 rpm tachs would be ideal if they weren't mechanical. I know I've seen some Isspro, VDO, and a few other gauges that are electric but they're generally smaller 2-1/16" dia and of course look different.
My pet peeve is these 29,312 rpm tachs that are pretty much useless after 5 grand anyway. My truck will never even see 5,000 rpm on a regular basis nor do most sbc's and everything past 4,000 is wasted 'acreage'.

[Sinister]

Originally Posted by Brad

Those 4,000 rpm tachs would be ideal if they weren't mechanical. I know I've seen some Isspro, VDO, and a few other gauges that are electric but they're generally smaller 2-1/16" dia and of course look different.
My pet peeve is these 29,312 rpm tachs that are pretty much useless after 5 grand anyway. My truck will never even see 5,000 rpm on a regular basis nor do most sbc's and everything past 4,000 is wasted 'acreage'.

Pet peeve of mine as well. How many people really need a 10,000 RPM tach?
Mine goes to 6000 RPM and I had to search for it.

[72armyswbtruck]

I think that I am gonna have to search my parts book.
Also great pics, time to right clik and save.

[teeitup]

IT'S NEVER cold where you LIVE!!!!!!!!!!!!!!!!! GREAT info Eric!!

[jeffspower]

I bet the one with the 2,800 redline was from a 6V53 Detroit, and the 3,200 redline a 4 53 inline Detroit. Rob (Blazerman) needs that one!

I base this on IIRC, some of the 4 53's were governed at 3,000. I used to work on several at a rock quarry. One was in a Trojan loader- I had that one set at 3,200 so it would dig into a pile better... the old Sundstrand torque converter had a little too high of stall

[beautimus]

if you happen to have an old corvette tach drive distributer laying around,
that 4000 rpm tach would be nice on a good ole small block daily driver.

[dieselarmy13]

Just to throw a wrench into the works here, but why does the 3200 redline dash have a vac. guage? Assuming its factory (not saying that it is) a diesel wouldn't have a vac. guage, as a diesel produces no vacuum, especially an old 2-cycle detroit

Very cool peices, nontheless, and thanks for sharing.

[too much stuff]

Originally Posted by dieselarmy13

Just to throw a wrench into the works here, but why does the 3200 redline dash have a vac. guage? Assuming its factory (not saying that it is) a diesel wouldn't have a vac. guage, as a diesel produces no vacuum, especially an old 2-cycle detroit

Very cool peices, nontheless, and thanks for sharing.

That is all original with the vac gauge. Somewhere on the truck there had to be vacuum. The other diesel cluster with out the vac gauge had a "low vacuum" idiot light in the fuel gauge head. Maybe a pump for brakes? I would think someone will know something about it.

[BLAZERMAN]

Those are some cool clusters Eric, first I have ever seen!

As far as the vac guage it more than likely came from a truck with an engine driven vacuum pump.

[badpeanut]

Nice writeup!

[rambler]

so the dashes are off of C30 and above trucks? I didnt think we had diesels in the c10 and 20's .. as stock..

[too much stuff]

Originally Posted by rambler

so the dashes are off of C30 and above trucks? I didnt think we had diesels in the c10 and 20's .. as stock..

Correct. I don't think the diesel was available in the c-30 even. The last diesel tach i pulled was in a 5500 gmc. It was already half crushed and i had them flip the carcass over so i could get to it.

[special-K]

Diesels run vaccuum pumps.

[1968SWBBigBlock]

I would guess any cluster with a VAC gauge came from a heavier truck with air brakes - you need to know the VAC level to make sure you have indicate air to put your brakes on.
I would guess 2ton or larger trucks would be the only ones to have the vac gauges

[dieselarmy13]

Originally Posted by 1968SWBBigBlock

I would guess any cluster with a VAC gauge came from a heavier truck with air brakes - you need to know the VAC level to make sure you have indicate air to put your brakes on.
I would guess 2ton or larger trucks would be the only ones to have the vac gauges

They would have an air pressure gauge, not a vac gauge. Air brakes require psi, not vac.

[too much stuff]

I have not seen a diesel tach set-up with an air gauge. Just vacuum or no gauge. All of the vacuum clusters have the same redline. That must mean something...

[gizmo1]

I had that problem with my 10000rpm tack, so I set it to 4 cyl operation. Idles at 1200 now and revs to 7000 wirh no problem . sure impresses people that do not know any better. It is in a stock 350 truuk

[too much stuff]

I should also add i don't see any difference in the P.C. or the inner and outer tins from a gas to diesel setup.