Today I picked up my car after my custom FMIC piping was made. Even tho he couldnt install my 30# injectors today, I explained to him I thought they were necessary because even tho my fuel pressures are fine, the EGT's go VERY VERY high (1400 cruising at 70mph before I had any IC at 5psi!!!!). I thought my injectors were just exhausted and I needed newer, bigger ones.

However, he mentioned I had my probe tapped in the wrong spot (I have it pretty much where the runners meet, almost in the third runner.... He told me I should have it in the downpipe and I am getting high EGT's because they are false reading since it's too close to the engine. He said he realized all the eclipse guys have it where I have it.

Now this guy really knows what he is talking about when it comes turbo imports and stuff... he's building a custom dragster with a Sktline engine. But I see EVERYONE here says put it in the fourth runner or in the middle.

What should I do? I am confused... could it be the injectors? Or is he right about getting false readings?

I have the Team Rip probe with the Autometer EGT gauge. By the way, I heard readings could get messed up if you cut the wire they give you/legnthen or shorten it??? Someone did my gauges for me so I am not sure if he cut the wire not knowing... can any of these thing be affecting the EGT's?







"Who needs a 4G63? I'd rather walk the competition than my crank..."

- Bill Hahn.... 420a GOD :bowdown

Dude, 1400 is fine for 70mph. You are fine.

Second, if you put it in the down pipe, then you will have to do calculations on whether you are in the temperature that will melt your pistons, as oppose to putting it in the runners (at the turbo manifold), and seeing the reading that you need!!! Do you really wanna take an egt reading, add XXX amounts, equals the actual temp???

-------jezreel
hrc stage 1, sfmu, ml, prokits, egt, boost gauge, apexi tt, costum dp, dynotune fp gauge. gst muff, turbo spoiler

nothing like driving with the windows down and the music low: i love hearing the turbo spool, swwwhhhttt!!!!
thanks for www.kaptainmyke.com for the sig hosting :thumbsup

if you put it in the dp, it is around 200* cooler. i dont really know where my egt's are crusing but, you need to get those 30lbers in there. they make a world of difference. i have my egt probe tapped on the side of the manifold in the 4th runner.

Originally posted by jsupetran
Dude, 1400 is fine for 70mph. You are fine. Second, if you put it in the down pipe, then you will have to do calculations on whether you are in the temperature that will melt your pistons, as oppose to putting it in the runners (at the turbo manifold), and seeing the reading that you need!!! Do you really wanna take an egt reading, add XXX amounts, equals the actual temp??? -------jezreel hrc stage 1, sfmu, ml, prokits, egt, boost gauge, apexi tt, costum dp, dynotune fp gauge. gst muff, turbo spoiler nothing like driving with the windows down and the music low: i love hearing the turbo spool, swwwhhhttt!!!! thanks for www.kaptainmyke.com for the sig hosting :thumbsup

I really don't think my car is fine either way... I mean it's 1400 and I'm not even in boost. And I can't even go passed 5K rpm with out the EGT's going passed 1600 in ANY gear. There's definitely a problem.

I'll see what happens after those 30# injectors tho... thanks.

Originally posted by DSMeclipseGS
Now this guy really knows what he is talking about when it comes turbo imports and stuff... he's building a custom dragster with a Sktline engine.

Well obviously he doesn't know jack about EGT placement and exhaust gas temperature. You want to keep the EGT probe as CLOSE as possible to the outlet of the cylinder, to give you the most accurate reading of the exhaust gas temperature. The farther the gas travels, the more it cools down, which will give you false readings of whats really coming out of your cylinder. Maybe you should fill this guy in before he grenades his dragster skyline motor :)

Originally posted by XtremeRS

Originally posted by DSMeclipseGS Now this guy really knows what he is talking about when it comes turbo imports and stuff... he's building a custom dragster with a Sktline engine.

Well obviously he doesn't know jack about EGT placement and exhaust gas temperature. You want to keep the EGT probe as CLOSE as possible to the outlet of the cylinder, to give you the most accurate reading of the exhaust gas temperature. The farther the gas travels, the more it cools down, which will give you false readings of whats really coming out of your cylinder. Maybe you should fill this guy in before he grenades his dragster skyline motor :)

lol.... ok. He says he's had experience with it in the downpipe and NOT fucking the engine up. I'll have him do the injectors and then tune before he touches the probe.

The problem with placing it close to the cylinder head is if you get a flame front out of the exhaust port it will give you a false high reading. Example, if you're running really rich and the fuel is still burning when the exhaust valve opens, the flame front hits the probe and shows a super hot temperature. You think you're running lean when you're running rich, and add fuel to an already rich setting. That's why the best way to tune is with a wideband O2 and a dyno.

Originally posted by Dave41079
The problem with placing it close to the cylinder head is if you get a flame front out of the exhaust port it will give you a false high reading. Example, if you're running really rich and the fuel is still burning when the exhaust valve opens, the flame front hits the probe and shows a super hot temperature. You think you're running lean when you're running rich, and add fuel to an already rich setting. That's why the best way to tune is with a wideband O2 and a dyno.

Thats why you don't tune to EGT alone...If you are running that rich to cause the flame front to hit your EGT gauge, then your A/F readings will be very, very rich, not lean, and will also make for some crappy power. IMO, the EGT should be placed anywhere BEFORE the turbo, and the closer it is to the exhaust outlet of the cylinder,the better the reading of how hot your exhaust gases really are inside the cylinder, which is what we are trying to monitor for safety to begin with..Yes, the BEST way to tune is with a dyno and wb o2

Well then my problem may be that I'm too rich. Cause my AF gauge reads rich .... even tho my fuel pressures are where it looks like they should be. I'll report back after the injectors go in tho. Thanks.

Originally posted by XtremeRS
Thats why you don't tune to EGT alone...

It works for me. :7

I tune a bit rich below 12 psi so I can use the pedal to get more timing advance. It makes a hell of a lot more power, I just keep my eye on the egt, if it gets ~1600F I'll push it to the floor to retard the timing after the boost gets up above 12 psi.


edit: Oh yeah, My thermocouple is right in front of cyl 3 so that it gets heat from 3 and 4.