Rx-7.com Suggestion For Egt
06-12-2003, 12:46 PM
#21
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Join Date: Apr 2002
Location: Bay Area, California
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Also keep in mind rotary exhaust gas temp can sometimes exceed the max reading on some guage, so it is necessery to move it further away from the exhaust port (like in the downpipe) so that the probe don't melt.
* happens a lot on DSMs, when they tap it into 1st runner *
* happens a lot on DSMs, when they tap it into 1st runner *
06-12-2003, 12:51 PM
#22
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Originally Posted by onboost' date='Jun 12 2003, 09:44 AM
egt is quite important for all the tuner and road racers out there. you can have perfect a/f ratio, and have an egt too high and can still pop your motor.
mike
06-12-2003, 09:34 PM
#23
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Join Date: Apr 2002
Location: NASA/JSC - Clear Lake, TX
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"1/8 npt" tells me very little. that's what the directions say, but neither my metric or SAE tap peices say that size. i'm going to lows tomorrow, that will fix things. i'll just get a nut that fits and either tap a hole that size, or if that doesn't hold, i'll just go to midus to get it welded on.
06-12-2003, 09:55 PM
#24
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Join Date: May 2003
Location: Dover DE
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NPT stands for National Pipe Thread. Your SAE and Metric tap and die sets will not have this normally. You have to buy a seperate tap to do this. You also will have to tap out the nut you will be using as well because it also will be SAE or metric thread. NPT is pipe thread wit a taper to it. One the nut is welded in place tap them together, this will give you the required taper needed for the probe to stay in place. The reason they use pipe thread is that it will stay locked in place better with the high temps that the probe will endure, other wise it may loosen under all the heating and cooling cycles it will encounter in the life of the probe.
06-13-2003, 11:52 AM
#26
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EGT's are a good thing to have when you get to tune your car on a dyno. The dyno usually will have a wideband O2 for you to use. But one of these tools alone isn't half as good as using both of them together.
06-13-2003, 12:25 PM
#27
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I know for a fact that Sears sells 1/8 NPT taps and it'll be less than $10.. If you tap the manifold or the ex housing you will need to remove them or you have the possibility of metal shavings falling down in to the ex port and doing some serious damage... If you put it in the front pipe you'll get inacurate reading and it will also show what is going on too late... The best place is in the ex housing, but then you also risk it breaking off from heat and running the end of the sensor threw your exaust blade.. Having a EX temp gauge is a great thing, but when put in the front pipe (the safest place) you don't get the best performance of the guage and in the ex housing or manifold you get the best performance, but risk it comming apart and distroying the ex wheel of your turbo or even worse falling back in to the ex port and blowing the engine... It's a damned if your do damned if you don't kind of thing...
also the reason the ex housing is the best place is because you will get a hot reading when you go rich due to the left over fuel combusting in the manifold and ex housing, you won't really see this in the front pipe because the ex temp drops dramaticly once it leave the turbo..
IE.. running lean you may get a 920'c reading in the ex housing, but only a 740 in the front pipe..
running perfict you may have a 820'c in the ex housing and get a 710'c in the front pipe..
running rich you may have 1000'c in the ex housing and a 750'c in the front pipe...
It's much easier to see 100 and 200'c temp difrences than 10 and 20'c temp difrences on the gauge and when you do minor tunning adjustment you will also see 10'c temp changes in the ex housing, but you won't be able to see the 1'c temp change in the front pipe etc...
also the reason the ex housing is the best place is because you will get a hot reading when you go rich due to the left over fuel combusting in the manifold and ex housing, you won't really see this in the front pipe because the ex temp drops dramaticly once it leave the turbo..
IE.. running lean you may get a 920'c reading in the ex housing, but only a 740 in the front pipe..
running perfict you may have a 820'c in the ex housing and get a 710'c in the front pipe..
running rich you may have 1000'c in the ex housing and a 750'c in the front pipe...
It's much easier to see 100 and 200'c temp difrences than 10 and 20'c temp difrences on the gauge and when you do minor tunning adjustment you will also see 10'c temp changes in the ex housing, but you won't be able to see the 1'c temp change in the front pipe etc...
06-14-2003, 03:05 AM
#28
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Location: Peoria, AZ
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Originally Posted by onboost' date='Jun 12 2003, 12:44 PM
1/8 npt
egt is quite important for all the tuner and road racers out there. you can have perfect a/f ratio, and have an egt too high and can still pop your motor.
as for location, down pipe, manifold, or turbing hsg, all don't matter that much. Its just what your numbers are referenced off at. If you are comparing, dp to dp temps, you should tap yours into the dp. the closer to the exhaust port the higher the temperature will be, and slightly faster response as well.
egt is quite important for all the tuner and road racers out there. you can have perfect a/f ratio, and have an egt too high and can still pop your motor.
as for location, down pipe, manifold, or turbing hsg, all don't matter that much. Its just what your numbers are referenced off at. If you are comparing, dp to dp temps, you should tap yours into the dp. the closer to the exhaust port the higher the temperature will be, and slightly faster response as well.
hmmmmmm?
06-15-2003, 02:50 AM
#30
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Join Date: May 2003
Location: Los Angeles CA
Posts: 67
You all got me interested now on this Wide Band O2 deal. Obviously the WBO2 takes precedence over an EGT gauge, but I am curious about A/F meters. If you have a WBO2 installed, does that make a A/F meter useless? Or is there some actual use for it with the WBO2?
Greg
Greg