Sup guys.
I used the search, and I DID the search 12 months ago when I first decided to build my custom turbo kit.
But this is very interesting, and I really want to konw what you all think about this questions (or opinions or thoughts).

When I got my turbo kit setup 6 months ago with EGT gauge, whenever I go uphill, or push the car 'harder' (not WOT or racing, just crusing) the EGT will rise, and if I go uphill, at around 2000RPM with a lower gear pushing upward, the EGT will go up faster till 800C degree (with turbo ok) now all this I understand coz I got the turbo, but then again I never know how the EGT will reads like if I have no turbo.

So recently I took out my engine and do this and that.
And yesterday I got everything back and I drove the first day with no turbo charged ok.
I realize that when I go uphill, with a lower gear, it still goes up close to 800C degree when I back off the gas. Or when I am on the highway at around ~55MPH, I use 5th gear to try to bring the speed up higher like 70MPH... the EGT will read higher and higher till 800C degree. HOW COME?

I always thought only turbo charged will bring the Exhaust gas to go that high temp, or will just a regular N/T is also that high?

But if a N/T is also reach that temperature, then when I was N/T, I push my car hard....so it definitely go above 800F then??? (or 1600F)

Just a thought on this issue! so please give me your opinion or knowledge on this!
Thanks guys!

Gil

BTW, today I put my turbo back on....everything back to normal...but a sad thing happened.... CEL... I will post this on another post!
Gil

i had my egt hooked up without a turbo, i was getting about the same readings.

Nice....

So now I am curious,
then why we have to worry about EGT so much after turbo charged but not when we are N/T???
I konw 1600F will melt our piston and etc...but why not when we are NOT turbo charged?

What's' the difference?
Thanks.
Gil

Its pretty simple. When there is no turbo, the EGT's are very similar to having a turbo. But, when the motor is NA, the ECU theoretically will be controlling all aspects of the air/fuel ratio, and the EGT's should NEVER get up to 1600 degress no matter what. If its running that lean, the ECU will supply more fuel. Its all automatic. Now, when we have a turbo added on, we are relying on fuel pressure(or other fuel system setups) to supply the correct amount of fuel, and the ECU has no room for adjustment to richen the air/fuel ratio under boost, which is why we can run lean too easily, and get up to or over 1600 degrees EGT.

^^^ exactly. since we have to modify certain critical parts of our fuel system (like the map sensor) and have to add on a rising frp....the chance for leaning out is greater. you shouldent lean out too much when your stock, but the possibility is definately there when your turbocharged or using nitrous. EGT's are also highly recommended for nitrous, since the same leaning condition can occour

OH....Thanks guys..
so even when we are NA, the engine still can go up and above 1600F, but because the ECU, everything is controlled automatically.

Then why don't someone make a ECU for turbo for our car? then we don't need or take the risk of running lean?
Well, I think there is one already for 1997 eclipse correct?

Well I guess as long as I run on the rich side, I am safe!
Thanks all.
Gil

No market that will offset the risk of investment in making a computer replacement of the oem 420 computer, that controls boost like the 4g63 cars. That's why when you start running boost, it is truely important to invest in gauges and not lean out the fuel.

The 97 afx ecu does not aid in controlling timing in relation to boost.

-------jezreel
hrc stage 1, sfmu, ml, prokits, egt, boost gauge, apexi tt, turbo xs rfl, haydans tranny cooler, costum dp, dr. uber groundwires, 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

OK.... just curious thoughts...and I only have a 1995 anyway...so no luck for me!

THanks all.
I got all the gauges I need so I am good... and this time.. I found out I am running lean.

Like around .86 on my A/F gauge. but before, no matter how I tune my car, I am running rich.

All I did was:
took my whole engine out, changed the headgaskets (so no more coolant to oil leakage)
Also put a brand new O2 sensor in there
and all other things.

And now when I run my car, i am lean, but it's good, I tune it back to .94-.96 so it's good.

Gil