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Michael Oritt
12-18-2006, 07:44 PM
In addition to the wiring I am also redoing the dash and instruments. Auto Meter makes OT, OP and WT guages in both mechanical and electrical configurations. Is there any real difference between the two in either accuracy or reliability?

Best--Michael Oritt, Elva Courier

WhatsThatNoise
12-18-2006, 09:20 PM
Can't think of anything better than the stock MGA gage for the Elva.

Mechanical is far better...

1) No guessing.....Fast response and reliability
2) No voltage regulators, no adapters, no wires & easy trouble-shooting.
3) Ease of installation.
4) One gage to look at.

Second best would be Racetech.....(Pegasus)

tr8todd
12-19-2006, 07:34 AM
Mechanical gauges are better. That being said, I run both. The mechanical sit in front of me and the electrical off to the side. With a British car, it offers piece of mind. If you run mechanical gauges, make sure you run metal or braided stainless lines into the cockpit. Those plastic ones are not alowed for racing. Nothing worse than having hot oil spray on your legs when you are out on the track.

WhatsThatNoise
12-19-2006, 08:18 AM
[ QUOTE ]
Nothing worse than having hot oil spray on your legs when you are out on the track.

[/ QUOTE ]
Great!.....Another sneaky little trick for my Pinto to pull.

Or that will be next years tech-peeve /ubbthreads/images/graemlins/nonono.gif

aeronca65t
12-19-2006, 10:46 AM
You can buy low-cost mechanical gauges in discount stores like AutoZone. I bought a mech. temp gauge for under $20. It came with a number of engine block adapters (none of them fit, but I was able to modify one using a lathe).
They have low-cost mech oil pressure gauges too but I used a spare aircraft gauge and homemade adapter that allows me to use an oil pressure warning light as well.(be sure to use copper line to the oil pressure gauge....not plastic line).
If you are running total-loss electrical (no alternator), a voltage gauge is a good idea too. My favorite gauge is the big red shift light I bought from Summit Racing. Under $35 and easy to adjust. I still have the teeny-tiny '78 Midget tach in the dash, but I never look at it.

JerryB
12-19-2006, 11:02 AM
Depends on two things....(at least in my mind).
1) packaging constraints
2)level of prep

Mechanical gages usually have 270* sweep while electric gages have 90* sweep. Therefore mech. have more defined visual reading points.

Electric guages have large transducers/sending units and might be problematic as to fit.

If you have a cheap motor, you might use cheap gages. That doesn't mean that a cheap gage is not doable. For my $ its Autometer (e-bay is a good cheap source of NEW) or Stewart Warner. Pretesting whatever you use might be advantageous. Clocking the gages are a good help.

Water pressure and oil pressure lights (big ones) are a help also.

Hap Waldrop
12-20-2006, 07:26 AM
I use mechanical gauge (Autometer) except for the tach, it's electric. I agree with Jerryb, buy the best and largest you can, I use on most of my cars 2 5/8" temp and pressure gauges, have notice no real difference in fluid filled vs not, use the 4" in dash Autometer tach, in the past I went for the memory feature, but then noticed I nevered used it, so the last Autometer tach I bought was the 4" in dash without memory. I like Autometer Sport Comp with black faces in roadsters.

Here's a pic of the gauges in Speedracer
www.acmespeedshop.com/_images/100-0004_IMG.JPG (http://www.acmespeedshop.com/_images/100-0004_IMG.JPG)

Eric
12-21-2006, 11:31 AM
[ QUOTE ]
Those plastic ones are not alowed for racing. Nothing worse than having hot oil spray on your legs when you are out on the track.

[/ QUOTE ]

I'm not sure that's universally true. I crew for a guy running CASC and SCCA races in GT3 (BMW 2002) who uses a plastic tube oil pressure gauge, clearly visible through the windshield and under the hood, and it has never occasioned comment at tech.

Tim Hollister
12-21-2006, 11:59 AM
[ QUOTE ]
[ QUOTE ]
Those plastic ones are not alowed for racing. Nothing worse than having hot oil spray on your legs when you are out on the track.

[/ QUOTE ]

I'm not sure that's universally true. I crew for a guy running CASC and SCCA races in GT3 (BMW 2002) who uses a plastic tube oil pressure gauge, clearly visible through the windshield and under the hood, and it has never occasioned comment at tech.

[/ QUOTE ]

From the SCCA's 2007 General Competition Rules (GCR):

9.3.27. FUEL, OIL, AND WATER LINES
All fuel, oil, and water lines, including gauge and vent lines, that pass into or through the driver/passenger compartment, shall be of steel tube or metal braided hoses or bulkheaded. The driver shall not be exposed to header tanks.



I've only been doing this a few years now but that rule has been there since at least 2001, and for good reason in my eyes. The rule applies unless something in the GT specs allows otherwise. I know it applies in the Production category.

Best wishes, and be safe!

Tim

JerryB
12-21-2006, 05:39 PM
"""""Best wishes, and be safe!

Tim """"" /ubbthreads/images/graemlins/iagree.gif

Common sense should prevail when something like this is not spelled out in the rule book.

Kinda like my story I always tell of arm restraints...asking which hand the driver writes his bank checks with......

I wouldnt use plastic or even the so-called "good" labeled nylon for manual oil pressure guages in my scooter!!

We still see cars with fuel gages in the drivers compartment also......famous words "I've been racing 15 years and never had a fire"

aeronca65t
12-21-2006, 11:33 PM
[ QUOTE ]
Here's a pic of the gauges in Speedracer
www.acmespeedshop.com/_images/100-0004_IMG.JPG (http://www.acmespeedshop.com/_images/100-0004_IMG.JPG)

[/ QUOTE ]


OK, that is nice.
Mine's more of a patchwork of cast-off or existing parts.
Steering wheel (10") is cheapie from JC Whitney. I cut the center out of an old Midget steering wheel and made an adapter from that. The column is shortened about 5" or so. Water temp (mechanical) is under $20 from AutoZone. Oil pressure gauge is old one from Aeronca. Stock tach and cheap Summit shift-light. The button on the right is for the Fiamm air horns....flaggers like 'em. Dash is home-brew "engine-turned". Shifter is made from a bed frame caster (price was right). Toggle swiches are freebies from local company (Allied Signal) and are high quality, US made. I'd like to mount the fuse box on the dash (like in plane).

We're required to wear arm restraints and I would anyway.....but I am not understanding the point of the "bank checks" comment at all??? /ubbthreads/images/graemlins/confused.gif


http://img.photobucket.com/albums/v170/aeronca65t/EMRA_06/sprite-dash.jpg

WhatsThatNoise
12-22-2006, 05:06 AM
here is the Pinto ......Impressive ain't it?
http://i50.photobucket.com/albums/f312/dlg208/PVGPSchenleyPark018.jpg

aeronca65t
12-22-2006, 07:05 AM
[ QUOTE ]
here is the Pinto ......Impressive ain't it?....

[/ QUOTE ]

Dave: I see you have a "mascot" riding along with you too. Mine's "The Lucky Lizard", strapped to the cage with zip-ties.

http://img.photobucket.com/albums/v170/aeronca65t/Cars/lizard.jpg

foxtrapper
12-22-2006, 08:13 AM
[ QUOTE ]
In addition to the wiring I am also redoing the dash and instruments. Auto Meter makes OT, OP and WT guages in both mechanical and electrical configurations. Is there any real difference between the two in either accuracy or reliability?

Best--Michael Oritt, Elva Courier

[/ QUOTE ]

Mechanical gauges carry the myth of superiority as a legacy from about half a century ago, when electric gauges were indeed pretty bad. Today, that's not the case.

I'd run electric, given the choice. The installation is much easier and neater. The price is usually higher though.

In the Autometer line, the low end is the autogage. The electric units have a smaller sweep than the mechanic, but that's normally not an issue for driving. The higher end that you're probably considering is the pro-comp. In this series the electric is the same wide sweep as the mechanical gauges.

DrEntropy
12-22-2006, 09:33 AM
For the application, my pref has always been mechanicals. Mostly for the sweep range difference. A quick glance at the 'short' sweep electric ones has always had me going back for another look as confirmation... not the best thing. And Dave said it: the dual WT/OP Smith's is a one-shot confirm. Nice vertical white line; press on. And I s'pose electric ones are reliable enough now, but I'm still of the linear, Newtonian school when it comes to a racing app. Just my 2p worth.

...and as soon as I saw Dave's blue critter I thought of Nial's lizard... then scrolled down and there he was! heh.

WhatsThatNoise
12-22-2006, 12:04 PM
[ QUOTE ]
I see you have a "mascot" riding along with you too. Mine's [i]"The Lucky Lizard"

[/ QUOTE ]
Yep...Cpt. Sparkles dot thought I should have it.....

Gonna have to ask her what its name is again. /ubbthreads/images/graemlins/confused.gif

I usually give it a pat on the head before I leave grid. /ubbthreads/images/graemlins/grin.gif

JerryB
12-22-2006, 02:14 PM
Kinda like my story I always tell of arm restraints...asking which hand the driver writes his bank checks with......

Nial wrote..........
""""We're required to wear arm restraints and I would anyway.....but I am not understanding the point of the "bank checks" comment at all??? """""""

It goes like this.....the loss of a hand or worse in the case of a severe roll over or crash due to an arm(s) flailing around might preclude the driver from writing a check (or worse) on Monday. When dialoging with a driver about this they really remember the story of writing checks then. /ubbthreads/images/graemlins/rolleyes.gif

aeronca65t
12-22-2006, 02:23 PM
Ah! OK...got it!

Michael Oritt
12-25-2006, 07:11 PM
Dave--

I like the Pinto's dash--very functional. Attached is a picture of my initial template for a new dash for the Courier. I'm using the small Auto Meter guages and the 5" Monster tach.

Best--Michael

WhatsThatNoise
12-26-2006, 07:59 AM
I wouldn't say I'm a gauge hawk or anything.
(I check them once per lap after exiting the last turn)

I really never look at the tach either.
I just hold her to the floor until it is out of cam. (about 5800)

Looks like your spending some quality time in the garage this winter. /ubbthreads/images/graemlins/yesnod.gif /ubbthreads/images/graemlins/thumbsup.gif

Hap Waldrop
12-28-2006, 08:05 AM
Well I am a guage hawk, I guess that's the engine builder in me. For those reasons I pride myself in being a great test driver, I normally can shake a car down alot better and quicker than even drivers faster than me. I never liked gauges behind the steering wheel, with bulky driving gloves on it noramlly take extra effort to look at them, for that reason I normally don't put anything behind the steering wheel in any of my cars.
I tell you guys what I tell folks when I instruct driver schools, you must be able to process information very quickly to be a good driver, in a a mere second you should be able to check the mirrors, make a shift, scan the gauges and still be in the middle of a battle, if you can master this, you will be the complete driver. I can not tell you how many non-gauge watching drivers I worked with over the years, it's hard for me to fix the problem when the driver gives me zero information.

WhatsThatNoise
12-28-2006, 09:52 AM
That's OK........

I still get more grief over my "Nino Farina" driving position. /ubbthreads/images/graemlins/grin.gif

DrEntropy
12-28-2006, 11:12 AM
Hap wrote: [ QUOTE ]
I can not tell you how many non-gauge watching drivers I worked with over the years, it's hard for me to fix the problem when the driver gives me zero information.

[/ QUOTE ]

Amen!

tony barnhill
12-28-2006, 11:16 AM
GAAAAAAHHHHHHHHH!!!! Something else!!

MGB12
12-28-2006, 03:52 PM
Speaking of guage watchers - Gordon Smiley liked to tell the story of the professional Porsche driver at LeMans.

Late in the night a driver brings in his Porsche 956 for a scheduled pit stop and driver change. Since the radio is out on the race car, he walks over to the team manager and tells him the oil pressure is fine but the guage is leaking. The team manager tells a mechanic to crimp the line to stop the leak.

After completion of the pit stop, the new driver for the car fires and procedes down pit road. The team manager asks the driver that had just been relived "Did you tell the new driver about the crimping of the guage line?" The driver says, "No, didn't you?" The manager says, "Don't worry he will notice there is no oil pressure and reduce speed back to the pits."

As you know, a lap LeMans takes about 4 minutes. The car screams by at full song, right on time. The team manager looks at driver number one and says that the new driver must have figured it out. About 4 minutes later it screams by again. In another 4 minutes, they hear the car coming but then silence.

The car comes coasting in with the engine not running. The team manager sticks his head in the door and the new driver says, "It loss oil pressure but I caught it right away".

Hap Waldrop
12-28-2006, 04:13 PM
Sounds like the guys I know Glen /ubbthreads/images/graemlins/smile.gif

Hap Waldrop
12-28-2006, 04:21 PM
[ QUOTE ]
GAAAAAAHHHHHHHHH!!!! Something else!!

[/ QUOTE ]

Don't worry Tony, we going to have David bugging the heck out of you for gauge readings after every session, after awhile you'll get it, just to keep him off your back /ubbthreads/images/graemlins/smile.gif

Some guys just can't handle alot of stuff while driving, I know alot of fast drivers who are bad at watching the gauges. The funniest thing I ever saw was a beginner who wouldn't change gears once he got to fourth gear on the track, he said there was just too much to concentrate on to shift gears, needless to say they took his novice permit back, which was the right thing to do, he was just too panic stricken to ever drive a race car. Heck, I'm more intimdated by normal street driving than I am on the race track, most drivers on the track have some talent and aren't talking on a cell phone /ubbthreads/images/graemlins/smile.gif

lesingepsycho
12-28-2006, 04:35 PM
I'll let my dash speak for itself. You can see it here. (http://memimage.cardomain.net/member_images/6/web/762000-762999/762889_3_full.jpg)
They are all electrical gauges and they are very accurate, very responsive and very reliable. It should also be noted that they all fit into the stock gauge locations. However, because it is hard to find a combo temp/oil press., you will likely have to find a spot to stash that extra gauge. The voltmeter to the left replaced the heat knob and the temp on the upper right was cut in. I also have an air/fuel ratio gauge that I intend to get in there one of these days. The only one that hasn't been swithched (yet) is the speedo... those sucker's are S-P-E-N-D-Y!!!

JACK

Hap Waldrop
12-29-2006, 07:13 AM
Jack, that's a nice layout for a street car. On a race car, a dash is a good place to save weight as well, the dash I pictured above is made out of .030" aluminum, it a feather, it floppy as a piece of raw bacon until it it mounted, all the bracing is aluminum as well, once mounted though, it quite stiff. I probably save 10-15 pounds by not work with a stock dash and using the thinnest aluminum I could get by with and mounted it in a fashion that would bring back rigidity.

Michael Oritt
12-30-2006, 08:24 PM
We finished cutting the dash today along the lines of the pattern I posted a few days back. We used .050 aluminum with a U-channel bent into the bottom and an L turned on each end for stiffness and appearance . I'm going to finish it in a nice black crackle paint and will post a picture in a couple of days when done.

Michael Oritt
01-04-2007, 07:37 PM
I wasn't happy with the way the crackle paint came out--the texture seemed to vary from spot to spot--so I wound up covering the dash panel in black vinyl. Attached see a photo--the empty hole is for a voltmeter which should arrive tomorrow. The switch panel is Moroso and the gauges Auto Meter mechanical.

Thanks to all for the advice and tips.

Best--Michael Oritt, Elva Courier

Hap Waldrop
01-07-2007, 09:36 AM
The secret to the wrinkle paint is heat. On a 90 degree up day nothing more than the power of the sun is needed but any other time I use a heat gun. The secret is to preheated what you going to spray and then keep the heat to after you spray it until you see the wrinkle come up on the surface. I used this method many times with great results.