egt prob

[miklaver]

i see every body is putting the egt prob in the #1 exhaust tube. has anyone put it in the collector and has the manifold wrapped with heat tape? if so what kind of egt's would you see?

 

[Slo2gen]

Most people actually put it in the #4 runner, it tends to be the hottest cylinder so it makes sense to but the probe in the hottest part. If you put the probe in the collector it the temps will drop a few degrees. With heat wrap it may rise some but not too much, to get the most accurate I would put it on the #4 runner.

 

[miklaver]

so if it is in the collector and i see 1900egt that would be bad. to lean.

 

[Locke]

Most people actually put it in the #4 runner, it tends to be the hottest cylinder so it makes sense to but the probe in the hottest part. If you put the probe in the collector it the temps will drop a few degrees. With heat wrap it may rise some but not too much, to get the most accurate I would put it on the #4 runner.

Most people are wrong, also. The cylinder furthest from the fuel feed will the be leanest (or most likely). With 3 leaks introduced into the rail (injectors) before the #1, the likelihood of the highest pressure drop at cylinder #1 will be the greatest. The ideal location to place the EGT sensor would be in the #1 primary, away from the feed, as it would have the best opportunity to be the leanest, and hottest.

so if it is in the collector and i see 1900egt that would be bad. to lean.

1900* is far too hot, especially if measured at the collector.

 

[miklaver]

now running 10.5:1 and 6 pounds of boost will that affect my egt's compared to everyone that runs 8.8:1?

 

[VelocitàPaola]

Most people are wrong, also. The cylinder furthest from the fuel feed will the be leanest (or most likely). With 3 leaks introduced into the rail (injectors) before the #1, the likelihood of the highest pressure drop at cylinder #1 will be the greatest. The ideal location to place the EGT sensor would be in the #1 primary, away from the feed, as it would have the best opportunity to be the leanest, and hottest.

True, but if it's an early style fuel system, the fuel rail internally doubles back on itself, so the injector furthest from the source is cylinder #4.

 

[bullettdsm]

now running 10.5:1 and 6 pounds of boost will that affect my egt's compared to everyone that runs 8.8:1?

1900* is WAY too hot. With 10.5 you may run a little hotter, but man, you should be down in the 1400 and 1500's.

IDK, but maybe the gauge is off. 1900 is just awfully high.

MB

 

[BigRand]

My EGT guage doesn't even go that high....my rule of thumb is, if your probe is in the runner on the manifold , 1650*F should be your abousolute max limit, if its anywhere after that or in the downpipe, I use 1450*F as the upper limit.

The thing about EGT's is that you want them to be hot really close to the upper limit at WOT, because if your not then there is still power to be made (assuming afr's and everything else on target), its when you go beyond that upper limit for extended time that things begin to want to melt.
Call me out if I'm wrong, but thats what I've been reading.

 

[miklaver]

I'm all set i was off on my injector scaler i just bumped it up some and a big difference. egt's are down to 1380 to 1400's boosting and 1100 or lower off boost. I Will try to tune for a slightly higher egt for more performance but i will proceed with cation.