Vac dash ? - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Solver · 03-18-2005, 05:11 AM

Was wondering if anyone can tell me where the factory vac dash hooks up to and where the line runs through. Just picked one up and not sure if I want to use it . any pics of setup would be great. Also what would it cost to add vaccuum to a tach dash would I only need the lens with both listed? or would I also need middle plate also?

krue · 03-18-2005, 07:58 AM

I believe the vacuum gage only came factory in the bigger trucks (c-40 and up).

Rod · 03-18-2005, 09:21 AM

You'll need a tach inner metal plate...outer metal plate and different tach type printed circuit to make it a tach vac cluster.

Hook a rubber the line to an intake manifold spigot somewhere near back of engine for vacuum.

byrd · 03-18-2005, 12:06 PM

with Rod. You might as well get you an old non vac or tach cluster and buy the conversion kit. All the parts Rod said you need are true except that you will need a tach & vac inner metal plate as the tack only one will not have the open spot for your vac gauge.You could probably round up all you need but imo it would be easier and to accomplish what you want to do as then all you need is an old working cluster that you could just restore the gauges you need to add to the kit for the conversion. My .02 Randy

67chevemall · 03-18-2005, 04:27 PM

I've been wondering about the vaccum gauge for a while now. Those of you who have it, do you ever use it? I think it would be great to know the engine vaccum!
Wouldn't it tell you when your gaskets and hoses are leaking?
Any kits out there?
So the factory ones are on the C-40's and up?

dmec · 03-18-2005, 07:40 PM

the truck shop in socal sells the kits.
vac conversion kit $155
tach vac conversion kit $255

68gmcdually · 03-18-2005, 07:50 PM

I bought a mint one out of a C-60 (truck included) and I am going to put it in my 930. I think that it is not necessary but it will be cool. My vac gauge hooks up with a 1/8" metal line.

67chevemall · 03-18-2005, 10:02 PM

tach vac conversion kit $255??
I'm a little slow, is this a tack and vacuum in one gauge?
Cheers

farside847 · 03-19-2005, 02:12 AM

Quote:

Originally Posted by 67chevemall

tach vac conversion kit $255??
I'm a little slow, is this a tack and vacuum in one gauge?
Cheers

I think its a kit to add both a tach and a vac. Two sep guages, but one kit.

Dual quad · 03-19-2005, 11:05 AM

Once the dash is complete, you would generally install a barbed brass 1/4" fitting on the back of the vac gage. A vac hose could then be passed throughthe firewall and connected to manifold vacuum. I have the vac gage and it is great to have this indication available.

Solver · 03-19-2005, 12:00 PM

Dual Quad where on the manifold did you tie into vaccuum?

Dual quad · 03-19-2005, 01:18 PM

Hmm, I posted a reply, but it disappeared. Anyway, I found an unported (below throttle plates) vacuum port on my Eddy 1406. But, you could also tee into your distributor vacuum advance line if you use manifold vacuum for advance. Or, you could find acces to the vacuumm port on one of the runners on your intake manifold.

03-18-2005, 05:11 AM	#1
Solver Registered User Join Date: May 2000 Location: Storm Lake, Ia Posts: 1,449	Vac dash ? Was wondering if anyone can tell me where the factory vac dash hooks up to and where the line runs through. Just picked one up and not sure if I want to use it . any pics of setup would be great. Also what would it cost to add vaccuum to a tach dash would I only need the lens with both listed? or would I also need middle plate also? Attached Images __________________ 1972 Cheyenne Super 20 LWB-Blue 1972 Cheyenne Super 10 LWB-Black 1972 Cheyenne Super 10 LWB-Red 1972 Cheyenne Super 10 LWB-green 1972 GMC 4x4 LWB-White 1971 Cheyenne 10 LWB-Ochre 1971 Cheyenne 20 Longhorn-Copper 1971 Cheyenne 20 Longhorn-Black 1969 Custom 10 LWB-lt blue 1968 GMC 3/4 ton-green 1968 1/2 ton swb stepside-silver 1967 Chevrolet CST 10 LWB-green 1967 Chevrolet custom 20 LWB-Maroon

03-18-2005, 07:58 AM	#2
krue Designated A-hole! Join Date: Mar 2003 Location: South Mississippi Posts: 36,448	I believe the vacuum gage only came factory in the bigger trucks (c-40 and up). __________________ "If it ain't broke, fix it 'til it is!" Being stupid ain't illegal. We're Still Debt Free Except for the House!!! www.daveramsey.com 70 GMC SWB Stepside project "Green Booger" soon to be 6.0l/4l80e 93 S-10 "Poppaw's Truck"

03-18-2005, 09:21 AM	#3
Rod Join Date: Dec 1999 Location: Eastern - Manitoba Canada, Winnipeg Posts: 4,369	You'll need a tach inner metal plate...outer metal plate and different tach type printed circuit to make it a tach vac cluster. Hook a rubber the line to an intake manifold spigot somewhere near back of engine for vacuum. __________________ Senior active founding member. 70 3/4 ton GMC Suburban 4x4 250/4 spd. 71 1/2 ton Suburban Chevy 4x4, 350/350 72 Chev 1 ton tow truck 402BB w/Holmes 440 wrecker on propane 2005 FLSTSCI Harley Springer 85 FXSB Harley Lowrider 72 Triumph 650 Bonneville 5spd "Poor people don't have hobbies" Quote from wife.

03-18-2005, 04:27 PM	#5
67chevemall Registered User Join Date: Apr 2003 Location: NB Posts: 3,367	I've been wondering about the vaccum gauge for a while now. Those of you who have it, do you ever use it? I think it would be great to know the engine vaccum! Wouldn't it tell you when your gaskets and hoses are leaking? Any kits out there? So the factory ones are on the C-40's and up? __________________ 1968 Chevy C10 307 3ott fleetside 1967 Chevy C/10 V8, 3spd, fleetside lwb.Sold 1967 Chev C/10 step, 383, M21. SOLD

03-18-2005, 07:50 PM	#7
68gmcdually Registered User Join Date: Feb 2004 Location: Fenelon Falls, ON Canada Posts: 1,454	I bought a mint one out of a C-60 (truck included) and I am going to put it in my 930. I think that it is not necessary but it will be cool. My vac gauge hooks up with a 1/8" metal line. __________________ James Bellwood 1968 930 Extend-A-Cab Dually 5.7l, 5 speed,

03-18-2005, 07:40 PM	#6
dmec Senior Member Join Date: Jun 2000 Location: yucaipa ca Posts: 580	the truck shop in socal sells the kits. vac conversion kit $155 tach vac conversion kit $255

03-18-2005, 10:02 PM	#8
67chevemall Registered User Join Date: Apr 2003 Location: NB Posts: 3,367	tach vac conversion kit $255?? I'm a little slow, is this a tack and vacuum in one gauge? Cheers __________________ 1968 Chevy C10 307 3ott fleetside 1967 Chevy C/10 V8, 3spd, fleetside lwb.Sold 1967 Chev C/10 step, 383, M21. SOLD

03-19-2005, 11:05 AM	#10
Dual quad Smell that burnin' rubber Join Date: Sep 2000 Location: Ontario Posts: 171	Once the dash is complete, you would generally install a barbed brass 1/4" fitting on the back of the vac gage. A vac hose could then be passed throughthe firewall and connected to manifold vacuum. I have the vac gage and it is great to have this indication available.

03-19-2005, 12:00 PM	#11
Solver Registered User Join Date: May 2000 Location: Storm Lake, Ia Posts: 1,449	Dual Quad where on the manifold did you tie into vaccuum? __________________ 1972 Cheyenne Super 20 LWB-Blue 1972 Cheyenne Super 10 LWB-Black 1972 Cheyenne Super 10 LWB-Red 1972 Cheyenne Super 10 LWB-green 1972 GMC 4x4 LWB-White 1971 Cheyenne 10 LWB-Ochre 1971 Cheyenne 20 Longhorn-Copper 1971 Cheyenne 20 Longhorn-Black 1969 Custom 10 LWB-lt blue 1968 GMC 3/4 ton-green 1968 1/2 ton swb stepside-silver 1967 Chevrolet CST 10 LWB-green 1967 Chevrolet custom 20 LWB-Maroon

03-19-2005, 01:18 PM	#12
Dual quad Smell that burnin' rubber Join Date: Sep 2000 Location: Ontario Posts: 171	Hmm, I posted a reply, but it disappeared. Anyway, I found an unported (below throttle plates) vacuum port on my Eddy 1406. But, you could also tee into your distributor vacuum advance line if you use manifold vacuum for advance. Or, you could find acces to the vacuumm port on one of the runners on your intake manifold.



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