PROFILE

I'm considering installing EGT gauges/sensors on my blown 502 project to help me prevent a meltdown.
I'm running Gil manifolds.Is anyone else running a similar set up and were did you install the sensors?
Thanks,Jeff

mcollinstn

Gils have a "perfect" spot for probes. Call Gil and they will fax you the placement diagram.

You can also put the probes into the heads themselves...

blown1500

Hello PROFILE,
Mcollinstn has the right idea. I would recommend cylinder #6-this seems to always be the worst.
When you install the probe, always measure the distance into the exhaust flow-deeper will give a higher reading and shorter gives lower. Also, don't rely just on the pyrometer-CHECK THE PLUGS regularly. The pyrometer is a great tool and is great for early warning!!!!

Tinkerer

Blown 1500--- Little confused here---When you say deeper do you mean into the head or down the header. I always heard that you will have a higher temp reading if the probe is drilled into the head. I heard the best place for the probe is about 3 inches into the header. I have LIGHTNING headers so mine are drilled into the #6 exhaust port about 1/8 inch from the header flange.

paradigm shift

Not in number 6 and not my motor but is this the location on exhaust port.

PROFILE

Thanks for the response everyone.
Blown1500, Do think I would be better off mounting the sensor in the head or manifold.I know the temp is going to read higher in the head,but is one better than the other?
Also can I get away with just running a sensor in#6 alone or sould I run one on the other side as well (1,3,5,7)?
Thanks

Tinkerer

That is where I installed mine. In #6 though. I didn't use the threaded fitting I just micked the thermocouple and drilled the head a couple of thousands larger. It is a tight fit and wont blow out

TSNAVE

In almost every dyno room/dyno header-set, and headers I've seen on race cars with data recorders. The probes have been about 1" from where the header flange meets the head. Also, you should use a digital pyrometer instead of an analog gauge so the response time is instantanious. By the time an analog gauge responds, it could be too late! I've installed probes in Stainless Marine manifolds by drilling and tapping a 1/8" NPT hole about 3/4"-1" away from the flange/mating surface. I also installed the probes in #7 and in #2. The leanest cylinders I have found. I would assume your GIL manifolds are similar. Good luck with your install!

blown1500

Hello, Guys,
TSNAVE has good info, but be aware, marine headers are double wall and if you put the probe in them, you have to seal it to both surfaces. The head idea is great. I would use the threaded fitteng because of Finagle's Rule-"If it can go wrong, it will".
Also, some guys don't want to do anything with their head.
My motor, the head is fine. No matter what style you go with, check the plugs ! ! when you have them right, note the temp shown on the egt and try to stay there or below. You cannot trust the exact temp given on the guage, digital or analogue. Too many variables. Change is what you are looking for. Whipple has a system that will turn on a light or buzzer wheh the temps get too high. If you are not LOOKING at the guage when something happens, it might be too late before you look.

Kanookstr

Gil Diagram