FredoSP

Hey Guys, im in the process of getting a Greddy EGT and I wanted to see some pictures of where you guys placed the probe. I know cyc #3 is the one most people do it in. This is what I have to work with (see pic).

- Fred

Phoenix GSR

everyone has s different opinion on this... I always put mine in the top of the turbo right off of the manifold so you get a reading off all 4 cylinders, plus there is usually plenty of room for the probe to stick out...

as you said most people prefer #3 cyl because they say it is the hottest...

when my first motor blew (I melted a piston with no signs of detonation doing an extended top speed run at 10 psi on a stock motor on a racetrack) it was the piston #1 (on the pass. side) that melted.. so I dont believe that #3 is the hottest..

just my opinion..

FredoSP

bump

shortyz

just get 4 probes and 4 meters :D

DeepSi

that is what a lot of racers do, but i dont think the avg street driver wants to do that

PressurizedSi

Hehe I see you removed your a/c condensor fan as well. Allows more room for the oil line feed. I heard the best place for an EGT is roughly 3" from the flange of the manifold.
I would weld a bung onto the manifold then screw the sensor into the bung. Cleaner look IMO.

FredoSP

Yeah but that pic was during the install, so the fan is back in now. I wanted to give you guys and idea of what the mani looks like.

There is another opt. me and DeepSi were saying instead of putting it directly on the mani, we can do it on the 45 degree tee right before the downpipe.

If you look in this picture, its the piece before the downpipe (on the right hand side of the floor). You will this affect the readings? I mean greatly?

DeepSi

I am thinking you will have lower temp numbers, because the turbo will cool down the temp, but as long as the numbers are consistent, there is no problem is there?

Farnsrocket

Supposed to be about an inch from the head on the #3 runner of the mani. People are afraid it will break and go into their turbo....bah!....it's supposed to get hot, why would it break?

D-Man

There's a problem with that,what if cyl #1,2 or 4 go red hot,having it in #3 wont show you shiet.If you mount a probe like that,do it the right way,mount a probe for each cylinder.If your only gonna use 1 probe,mount it in the downpipe.The reading will be lower but if any cyl goes red hot at least you'll see it.

DeepSi

Another problem that has arisen is where do you mount the EGT Probe, if the manifold is already on the car. The Greddy manifold is kinda hard to take off and on. so some people have told us to just leave the car on, and drill the manifold. but wont the particles from drilling damage the turbine? wont it be easier to mount on the downpipe, since it is easier to take off and mount.

Farnsrocket

I think it also depends on what you are using the EGT gauge for. If you want to monitor all 4 cylinders, then I guess putting it in the downpipe is the way to do that. Although, I wonder what the difference in temperature is if the probe is in the downpipe and one of the cylinders becomes lean.........does anyone have any real hard evidence of the temp change in this scenario? And, what is the temp reading supposed to be at the downpipe location? Who has any real readings at the downpipe location from a well tuned car? This reading at the downpipe location is pretty much useless if you want to know an actual temperature from your head.............I would think you would want to know that for sure. The #3 is supposed to be the hottest spot on the engine from what I understand, and when I have my car running right, I want to know what the hottest temperature the car is producing and assume the others are running OK. If something like a fuel injector goes bad, my fuel pressure gauge should show that. Like I said, some may want to monitor all 4 cylinders.
I would not drill the mani on the car and mount the egt probe.....I would take it off the car........I would not want any shavings going by my turbo. You could drill it on the downpipe and not take the downpipe off since the shavings will just go out the muffler, unless you need to take the DP off.

falcongsr

i'd like to know how monitoring all 4 cylinders downstream would tell you that a cylinder is about to let go. you'll be seeing an averaged temp and you're probly not going to notice. #3 beign the hottest doesnt mean its the most likely to melt - too many other variables there. just my opinion.

DeepSi

yeah you will be seeing an avg, but wont you see a drop in the avg and know something is wrong and you will slow down?

FredoSP

true true, so now im confused where to put this sucker!!
I just want aheads up to keep an eye on things.

Farnsrocket

Like I said, I don't know what kind of difference it would show if your probe was in the downpipe and one cylinder went lean. I would stick with #3 and get a true reading of the hottest cylinder.

shortyz

yeah drilling with it on the car is kind of dangerous. u could fuckup your turbo.

FredoSP

yupperz!!