oil pressure and water temp gauges

h500r · 05-29-2009, 12:28 AM

new to dragsters , do you dragster guys run electric or mech gauges for oil and water ?
thanks for any help in my decission

I have one gauge so far (volt meter)
autometer ultralite.
new s&w 235" rear engine swingarm 582 bbc just starting on the electrical

Bill Baer · 06-01-2009, 04:38 PM

We use a mechanical oil pressure gauge and an electric water temp gauge. At one time I used a mechanical temp gauge but the capillary tube is difficult to run and easy to damage. I use autometer gauges the mechanical oil pressure gauge which is liquid filled to help resist the vibrations which may not be necessary they (autometer) also have a trick low temperature electric gauge the I really like because it helps keep the launch temp accurate.
A note of caution about using electric temp or oil gauges they must have a good ground to be accurate and the motor plate,especially if it's anodized makes for a poor ground connection to the chassis. I run a seperate ground wire for my temp gauge and the transbrake solenoid I also ground the battery to the starter. My Dyno guy has seen on incidence of picking up power by running a ground wire from cylinder head to cylinder head and back to the battery,I have not tried this myself but it makes sense that the ignition needs a good ground path too. You also need to make sure that the sending unit is not at the high point in the cooling system or you may have to run the water pump to get an accurate reading and you don't want the sending unit in an air pocket.

If you use a mechanical oil pressure gauge I would use a #4 AN Braided line as it will not dampen the response of the gauge don"t use copper, aluminum or steel may be ok but the #4 AN (Earls/braid covered rubber)is easy to route and has been reliable.
I also run a large 30# Idiot light (Longacher or Speedway motors) I also have an Idiot light for the trans brake that lets me know it's energized and I have a shift light that continues remind me that I have overreved the motor on the burnout

As far as wiring goes make sure that everything can be shutoff by one switch [/U]and that it has a sufficent aperage rating to handle the load.
I have seen a couple of cars equiped with a cable to turn off or on the main power switch with a lever in the cockpit which I think is a good idea especially when I'm strapped in ready to go and I forgot to turn the damn switch back on

I don't run the starter current thought the main power switch it will eventually fail and if you using an electric fuel pump put a safety pressure switch in it circuit.

Well that probably a lot more info than you wanted anyway

but if you have any questions let me know.

h500r · 06-02-2009, 12:30 AM

can never be too much info

that really helps thank you !!

S/G 386N · 06-02-2009, 08:27 AM

I also use mechanical oil and electric water. However, make sure you have a spare water sending unit. Never fails that once a year, mine will quit reading accurately half way through a race.

Michael Pliska · 06-02-2009, 01:09 PM

Disclosure notice: I am the engineering manager for a gauge manufacturer (ISSPRO, Inc).

That said, I have been hard-pressed to do away with old-school mechanical gauges. I pulled my old bracket car out of mothballs last year, and continue running the 30 year old mechanical oil pressure and coolant temp gauges, but I have added modern electronic gauges (actually prototype test units from work) in parallel (hooked to a tee on oil pressure, and the other head for coolant temp). The modern sensors have come a long way, and I trust them as much as the mechanical gauges. My mechanical coolant temp gauge still sticks occasionally, and the electric one tells me what I'm really running for temperature.

If your electric oil pressure sensor uses only two wires, then it is an electromechanical potentiometer based unit and not very reliable. If it is a 3-wire unit then it is likely a solid-state capacitance based unit, and these are typically reliable.

The electronic temperature sensors are typically thermistor-based. While this general technology has not evolved in decades, the mechanical design of the units have changed a bit (providing better thermal conductivity for quick response, and better mechanical durability of the electronic components). Typically the newer (and more durable) designs of sensors have integral electrical connectors and an isolated ground (2 wires running to it).

I am in the process of returning my Super-Gas car to the track after a 15 year hiatus. I will start out with the old mechanical gauges in it, but will probably convert it to electronic gauges when I have the spare time.

Regards,

Chris Williams · 06-02-2009, 01:53 PM

Not much help for you, but we switched from mechanical gauges to all electronic through a Racepak w/ a Racepak dash over the winter. Absolutely love it. Not only do you get good info, but it's all logged.

07-05-2016, 03:44 PM

We now carry our full sweep performance electronic gauges:

http://shop.classicinstruments.com/v...white-series-2

Tom Goldman · 07-05-2016, 04:03 PM

Think about a Racepak digital dash . Gauges are really only useful for warm up , on the track the only thing you need is an oil pressure warning light .
If you're looking at the gauges on the track , you have given your engine more attention than your opponent !
And that comes from someone who lost a $5K final doing just that on the starting line .

Michael Pliska · 07-05-2016, 06:39 PM

Wow, this is an old thread! Since my last post on this subject we have come up with a few relevant items. For standalone electronic EV2 gauges we now have an output driver module, which allows you to control up to a 10 amp device with the gauge, programmable as a high or low switch point along with some activation delays, all programmed separately from the built-in warning light on the gauge. I have used this to activate the cooling fans on my race car, and consequently cool the engine down to a consistent temperature between rounds. The module is P/N R82006 and adds onto any electronic EV2 gauge.

We also used my S/G car and tow rig (which also gets bracket raced) as a test bed to develop a datalogger add-on for our Performax series of databus-based gauges. You can have analog-appearing gauges which read off of the same sensor as your datalogger, and each of the gauges just connects to the same 3 wires that run from the main controller. The main controller is R82000 and the datalogger module is R82007. It is a very reasonably priced way to get into datalogging. Please PM me if you have any questions.

jim hensley · 07-21-2016, 12:28 AM

just a comment on gauges. a couple of years ago, I was intrigued by the digital gauges, and I installed a pair of water temp, oil pressure digital electric gauges in my car. they would read fine when the car was idling, but once power was applied, the gauges would go crazy, flickering very fast so you could not read them. I contacted the manufacture and they had no idea what the problem was. I suspected a grounding issue, but rather than fool with it, I put the mechanical gauges back on and problem solved. Still curious what it could have been.

05-29-2009, 12:28 AM	#1
h500r Junior Member Join Date: May 2009 Posts: 2 Likes: 0 Liked 0 Times in 0 Posts	oil pressure and water temp gauges new to dragsters , do you dragster guys run electric or mech gauges for oil and water ? thanks for any help in my decission I have one gauge so far (volt meter) autometer ultralite. new s&w 235" rear engine swingarm 582 bbc just starting on the electrical Last edited by h500r; 05-29-2009 at 12:30 AM.

06-01-2009, 04:38 PM	#2
Bill Baer Senior Member Join Date: Jul 2007 Location: Nothern IL Posts: 596 Likes: 1 Liked 1 Time in 1 Post	Re: oil pressure and water temp gauges We use a mechanical oil pressure gauge and an electric water temp gauge. At one time I used a mechanical temp gauge but the capillary tube is difficult to run and easy to damage. I use autometer gauges the mechanical oil pressure gauge which is liquid filled to help resist the vibrations which may not be necessary they (autometer) also have a trick low temperature electric gauge the I really like because it helps keep the launch temp accurate. A note of caution about using electric temp or oil gauges they must have a good ground to be accurate and the motor plate,especially if it's anodized makes for a poor ground connection to the chassis. I run a seperate ground wire for my temp gauge and the transbrake solenoid I also ground the battery to the starter. My Dyno guy has seen on incidence of picking up power by running a ground wire from cylinder head to cylinder head and back to the battery,I have not tried this myself but it makes sense that the ignition needs a good ground path too. You also need to make sure that the sending unit is not at the high point in the cooling system or you may have to run the water pump to get an accurate reading and you don't want the sending unit in an air pocket. If you use a mechanical oil pressure gauge I would use a #4 AN Braided line as it will not dampen the response of the gauge don"t use copper, aluminum or steel may be ok but the #4 AN (Earls/braid covered rubber)is easy to route and has been reliable. I also run a large 30# Idiot light (Longacher or Speedway motors) I also have an Idiot light for the trans brake that lets me know it's energized and I have a shift light that continues remind me that I have overreved the motor on the burnout As far as wiring goes make sure that everything can be shutoff by one switch [/U]and that it has a sufficent aperage rating to handle the load. I have seen a couple of cars equiped with a cable to turn off or on the main power switch with a lever in the cockpit which I think is a good idea especially when I'm strapped in ready to go and I forgot to turn the damn switch back on I don't run the starter current thought the main power switch it will eventually fail and if you using an electric fuel pump put a safety pressure switch in it circuit. Well that probably a lot more info than you wanted anyway but if you have any questions let me know. __________________ Bill Baer 3391 SC, 339B SC, QR

06-02-2009, 12:30 AM	#3
h500r Junior Member Join Date: May 2009 Posts: 2 Likes: 0 Liked 0 Times in 0 Posts	Re: oil pressure and water temp gauges can never be too much info that really helps thank you !!

06-02-2009, 01:09 PM	#5
Michael Pliska Member Join Date: Oct 2008 Location: Happy Valley, OR Posts: 260 Likes: 0 Liked 0 Times in 0 Posts	Re: oil pressure and water temp gauges Disclosure notice: I am the engineering manager for a gauge manufacturer (ISSPRO, Inc). That said, I have been hard-pressed to do away with old-school mechanical gauges. I pulled my old bracket car out of mothballs last year, and continue running the 30 year old mechanical oil pressure and coolant temp gauges, but I have added modern electronic gauges (actually prototype test units from work) in parallel (hooked to a tee on oil pressure, and the other head for coolant temp). The modern sensors have come a long way, and I trust them as much as the mechanical gauges. My mechanical coolant temp gauge still sticks occasionally, and the electric one tells me what I'm really running for temperature. If your electric oil pressure sensor uses only two wires, then it is an electromechanical potentiometer based unit and not very reliable. If it is a 3-wire unit then it is likely a solid-state capacitance based unit, and these are typically reliable. The electronic temperature sensors are typically thermistor-based. While this general technology has not evolved in decades, the mechanical design of the units have changed a bit (providing better thermal conductivity for quick response, and better mechanical durability of the electronic components). Typically the newer (and more durable) designs of sensors have integral electrical connectors and an isolated ground (2 wires running to it). I am in the process of returning my Super-Gas car to the track after a 15 year hiatus. I will start out with the old mechanical gauges in it, but will probably convert it to electronic gauges when I have the spare time. Regards, __________________ Michael Pliska 643 S/G

06-02-2009, 01:53 PM	#6
Chris Williams Member Join Date: Mar 2009 Location: Woodinville, WA Posts: 401 Likes: 0 Liked 0 Times in 0 Posts	Re: oil pressure and water temp gauges Not much help for you, but we switched from mechanical gauges to all electronic through a Racepak w/ a Racepak dash over the winter. Absolutely love it. Not only do you get good info, but it's all logged. __________________ Chris Williams 6304 SC, TD, ET

06-02-2009, 08:27 AM	#4
S/G 386N Member Join Date: Sep 2008 Location: Fishers, IN Posts: 103 Likes: 0 Liked 0 Times in 0 Posts	Re: oil pressure and water temp gauges I also use mechanical oil and electric water. However, make sure you have a spare water sending unit. Never fails that once a year, mine will quit reading accurately half way through a race. __________________ JJ Nance '06 Don Davis C5 Corvette

07-05-2016, 03:44 PM	#7
Classic Instruments Guest Posts: n/a	Re: oil pressure and water temp gauges We now carry our full sweep performance electronic gauges: http://shop.classicinstruments.com/v...white-series-2

07-05-2016, 04:03 PM	#8
Tom Goldman VIP Member Join Date: Jan 2003 Location: Allentown,PA Posts: 2,436 Likes: 776 Liked 700 Times in 204 Posts	Re: oil pressure and water temp gauges Think about a Racepak digital dash . Gauges are really only useful for warm up , on the track the only thing you need is an oil pressure warning light . If you're looking at the gauges on the track , you have given your engine more attention than your opponent ! And that comes from someone who lost a $5K final doing just that on the starting line . __________________ Tom Goldman 1500 SG , 1506 STK

07-05-2016, 06:39 PM	#9
Michael Pliska Member Join Date: Oct 2008 Location: Happy Valley, OR Posts: 260 Likes: 0 Liked 0 Times in 0 Posts	Re: oil pressure and water temp gauges Wow, this is an old thread! Since my last post on this subject we have come up with a few relevant items. For standalone electronic EV2 gauges we now have an output driver module, which allows you to control up to a 10 amp device with the gauge, programmable as a high or low switch point along with some activation delays, all programmed separately from the built-in warning light on the gauge. I have used this to activate the cooling fans on my race car, and consequently cool the engine down to a consistent temperature between rounds. The module is P/N R82006 and adds onto any electronic EV2 gauge. We also used my S/G car and tow rig (which also gets bracket raced) as a test bed to develop a datalogger add-on for our Performax series of databus-based gauges. You can have analog-appearing gauges which read off of the same sensor as your datalogger, and each of the gauges just connects to the same 3 wires that run from the main controller. The main controller is R82000 and the datalogger module is R82007. It is a very reasonably priced way to get into datalogging. Please PM me if you have any questions. __________________ Michael Pliska 643 S/G

07-21-2016, 12:28 AM	#10
jim hensley Junior Member Join Date: Mar 2012 Location: columbia tn Posts: 50 Likes: 0 Liked 0 Times in 0 Posts	Re: oil pressure and water temp gauges just a comment on gauges. a couple of years ago, I was intrigued by the digital gauges, and I installed a pair of water temp, oil pressure digital electric gauges in my car. they would read fine when the car was idling, but once power was applied, the gauges would go crazy, flickering very fast so you could not read them. I contacted the manufacture and they had no idea what the problem was. I suspected a grounding issue, but rather than fool with it, I put the mechanical gauges back on and problem solved. Still curious what it could have been.