Dysfnctnl85

Since I have a divided turbo, the best placement for the EGT will be in the downpipe, I think.



The problem is, there's no way to tap for the sensor "holder" so to speak into the DP. There simply is not enough metal. So, is it possible to purchase a bung (like my wideband has) to weld onto the DP and make this whole process gravy?

ryosuke_fc

Yes, you would buy a bung and weld it onto the pipe. When I bought my Greddy PE used on ebay, the guy had already welded the bung into the midpipe. You just need to find something that is the same thread pattern as what is on your EGT sensor.

djgiantrobot

is there any point in putting the EGT all the way in midpipe? i thought putting it in the downpipe even was pushing it. If you can't get it directly into the turbine housing cuz its divided i'd suggest going for the manifold runner on the rear rotor, or front depending on how you've plumbed your fuel system.

Dysfnctnl85

I've been told to avoid placing the EGT in any of the exhaust manifold runners because I would be seeing a bias reading.



I'm gonna try and pickup one of those bungs today.



Thanks guys.

djgiantrobot

biased yes because you'd only see the EGTs coming out of one rotor, thats why the optimal location is the turbine housing itself. However, all things equal, i'd rather have the reading off of one rotor than put the probe after the turbo and have it cooled off like 200 degrees

teknics

i have a divided t78, and will be using an undivided HKS cast manifold, should i put an EGT probe where the two runners come together near where the turbo mounts?



kevin.

Dysfnctnl85

Hmmmm...I guess I'd like to hear what other people have to say as well. I mean, I can surely put it in the rear rotor runner (say that three times fast) with ease, but then again...I dunno. I guess it would be better to run TWO EGTs but that's just excessive .

djgiantrobot

if you can put it where the two runners come together thats prob a good place for it. I just say the rear rotor because that seems to be the rotor that generally runs lean first if there is a problem and the one that blows more than 50% of the time. Tune for the more accident prone rotor i'd imagine. I'm definately of the school of having as much information as possible about whats going on with the engine, but multiple EGTs might be going a bit far unless its in an airplane or like somekinda uber ems where you can trim fuel and timing for each rotor separately. Tuning with EGT alone isn't an exact science, but its a good piece of information to have for the overall picture.

Dysfnctnl85

Hmmm, with that being said I am leaning towards putting the probe on the rear rotor.



I should have a disclaimer at the bottom of my posts, about how I know nothing about rotaries. LOL.

BLUE TII

Optimal EGT placement in a divided manifold is one in each runner before the turbo.



Then if there is a runner that is reading higher you know it is probably leaner and you can adjust your fuel injector trim settings to compensate (if engine management allows) or really correct the problem by redesigning the intake runner(s) restricting flow.



You say semi-cosmo equiped 1st gen, so I assume you are using 13BRE Cosmo manifolds. I have been told their flow is fairly even so EGTs should be fairly balanced between rotors.



I have been told the 3rd gen 13BREW has poor lower intake manifold design that limits flow to front rotor, so rear runs leaner and usally blows first.