4 EGT to 1 Switched Gauge Install
by Pat Signorino & Shane Craddock | August 8, 2004 10:30 am
Forward: We do NOT reccommend drilling into your ex. manifold with it on your car. Shane and Pat pulled the motor shortly after, and when Shane pulled the head, he found evidence that this procedure cannot be performed safely in this manner. The head had to be machined proffessionally to remove the damage where some of the shavings had been smashed repeatedly before exiting the engine. Apparently, some of the shavings were left in the manifold, and upon starting the engine, they were sucked in on a down stroke, and caused the damage. It has been said on the message board that you can do this procedure with the car running to fix the problem, but we think it would be to cramped, and way too HOT! See this link for more info Gecko 2 Head machine work
4 EGT to 1 Switched Gauge Install
Recently, Shane Craddock installed 4 Westach EGT Probes in his Exaust Manifold, and hooked them up to a single switched Westach Gauge. The install was done with the manifold on the car, which normally is not recommended because metal shavings fall into the manifold, and can get stuck in the turbo, but the procedure can be done with the use of some simple tricks. EGT Preliminary test results at the bottom of the page.
Here’s a pic of the special drill bit used to cut through the manifold. 
Show here are some pictures of ways to get the metal shavings out of the manifold. First was the use of a magnet tipped utility tool, and second a more difficult item to get, a vaccuum attatchment (only use when Girlfriend/Wife is not looking. 
Next you need to “tap” the holes you drill in order to give the EGT “bungs” something to screw into securely. We’ve learned to always use the special “tapping” oil to keep the tap working correctly. 
Progress! 
Now, all that’s left to do is hook them all up to the switch, do some testing, and tidy up all the wires. Not too hard of a project. 
Test Results… 3S-GTE 4 EGT Temp Comparo
7/1/2001
4 Cyl EGT Comparo Info
75F – 60F in the shade
By: Pat Signorino and Shane Craddock
Shane’s Test Car (AKA Gecko2):
1991 MR2 Turbo 10PSI with 50 Trim wheel upgrade, and 1 Spal Fan on Stock Intercooler, 170 degree Stant Thermostat.
The car is not at the limit in terms of boost/heat. #2 and 3 cylinders do appear to be marginally hotter than 4 and 1. A simple EGT probe in the #3 cylinder is reccommended for all high HP Gen 1 US 3S-GTE’s. Warning temperature should be around 1550 degrees F. Once exceeded, things may already be at 1600F due to the slight lag inherent in EGT’s. If you see temps above 1600, you know that you are running lean, or something else is wrong with your engine. Keep in mind that these numbers may work for a pretty much stock car, but every car will be slightly different. Use this info at your own risk.
Hottest Cylinders in order 2,3,4,1 The difference between 1 and 2 is varying around 25 degrees F at 1400
Warm Idle Temps
Cyl
1 950
2 950
3 930
4 925
______________________________________
4500rpm 62mph 3rd gear constant
Cyl Temp
1 1405
2 1425
3 1410
4 1405
3000rpm 56mph 4th gear constant
Cyl Temp
1 1415
2 1435
3 1420
4 1410
_______________________________________
3rd gear runs max temp shift point 7,000
Cyl Temp
1 1550
2 1575
3 1550
4 1550
4th gear runs max temp shift point 6,200
Cyl Temp
1 1550
2 1585
3 1580 (1600 reached on one pull at 7000 rpm)
4 1580
Forward: We do NOT reccommend drilling into your ex. manifold with it on your car. Shane and Pat pulled the motor shortly after, and when Shane pulled the head, he found evidence that this procedure cannot be performed safely in this manner. The head had to be machined proffessionally to remove the damage where some of the shavings had been smashed repeatedly before exiting the engine. Apparently, some of the shavings were left in the manifold, and upon starting the engine, they were sucked in on a down stroke, and caused the damage. It has been said on the message board that you can do this procedure with the car running to fix the problem, but we think it would be to cramped, and way too HOT! See this link for more info Gecko 2 Head machine work
4 EGT to 1 Switched Gauge Install
Recently, Shane Craddock installed 4 Westach EGT Probes in his Exaust Manifold, and hooked them up to a single switched Westach Gauge. The install was done with the manifold on the car, which normally is not recommended because metal shavings fall into the manifold, and can get stuck in the turbo, but the procedure can be done with the use of some simple tricks. EGT Preliminary test results at the bottom of the page.
Here’s a pic of the special drill bit used to cut through the manifold.
Show here are some pictures of ways to get the metal shavings out of the manifold. First was the use of a magnet tipped utility tool, and second a more difficult item to get, a vaccuum attatchment (only use when Girlfriend/Wife is not looking.
Next you need to “tap” the holes you drill in order to give the EGT “bungs” something to screw into securely. We’ve learned to always use the special “tapping” oil to keep the tap working correctly.
Progress!
Now, all that’s left to do is hook them all up to the switch, do some testing, and tidy up all the wires. Not too hard of a project.
Test Results… 3S-GTE 4 EGT Temp Comparo
7/1/2001
4 Cyl EGT Comparo Info
75F – 60F in the shade
By: Pat Signorino and Shane Craddock
Shane’s Test Car (AKA Gecko2):
1991 MR2 Turbo 10PSI with 50 Trim wheel upgrade, and 1 Spal Fan on Stock Intercooler, 170 degree Stant Thermostat.
The car is not at the limit in terms of boost/heat. #2 and 3 cylinders do appear to be marginally hotter than 4 and 1. A simple EGT probe in the #3 cylinder is reccommended for all high HP Gen 1 US 3S-GTE’s. Warning temperature should be around 1550 degrees F. Once exceeded, things may already be at 1600F due to the slight lag inherent in EGT’s. If you see temps above 1600, you know that you are running lean, or something else is wrong with your engine. Keep in mind that these numbers may work for a pretty much stock car, but every car will be slightly different. Use this info at your own risk.
Hottest Cylinders in order 2,3,4,1 The difference between 1 and 2 is varying around 25 degrees F at 1400
Warm Idle Temps
Cyl
1 950
2 950
3 930
4 925
______________________________________
4500rpm 62mph 3rd gear constant
Cyl Temp
1 1405
2 1425
3 1410
4 1405
3000rpm 56mph 4th gear constant
Cyl Temp
1 1415
2 1435
3 1420
4 1410
_______________________________________
3rd gear runs max temp shift point 7,000
Cyl Temp
1 1550
2 1575
3 1550
4 1550
4th gear runs max temp shift point 6,200
Cyl Temp
1 1550
2 1585
3 1580 (1600 reached on one pull at 7000 rpm)
4 1580
Source URL: https://midshiprunabout.org/mk2/4-egt-to-1-switched-gauge-install/