Exhaust gas/manifold temperature. Highest recorded temps?

[Steampunk]

Can anyone provide figures for what they have seen as the highest temperature that the exhaust manifold reaches please?
Preferably for a naturally aspirated engine, but any figures from any engine will suffice.

I would really appreciate input from those who have race-cars and those who take theirs to the track regularly.

Cheers

Andrew

[Sean]

I cant talk for NA cars, but we've tested and tuned a turbo 1.6 with EGT and AFR so I can give yoyu some idea of our findings.

Once the car is running at normal water and oil temps we start tuning to EGT and AFR. Saw figures over 950 dec celcius, but generally tried to not go over 900.

Remember though that EGT is only part of the picture, there are lots of reasons for high EGT.


Rich AFR from a boost leak will give you high AFRs cause excess fuel is still burning as it passes the probe, but the engine is safe. The temp probe is not in the cylinder it's after it, so the heat is not in a place that will do damage but in experenced EGT tuners will still be tryng to add fuel to correct the EGT.

Cutting down your timing will also raise your EGT, but agai, no major stress on yout engine.

I also know of a tuner who cooked an engine that "looked safe".
He adjustment the intake cam gear and did not compensate for it with the CAS (dumbass), showed low EGTs, but the engine went bang.

[mx52nv]

Saw figures over 950 dec celcius, but generally tried to not go over 900.

Another turbo 1.6 here and highest EGT temp I have seen on my car was on a 42 degree day (track temps were over 50 degrees) and my gauge hit 960-970 degrees

As I was doing Autokhana, it was a quick bursts of under 1 min to 1.5 mins.

Then find (read fight for) the shadiest spot and cool down

[Sean]

Saw figures over 950 dec celcius, but generally tried to not go over 900.

Another turbo 1.6 here and highest EGT temp I have seen on my car was on a 42 degree day (track temps were over 50 degrees) and my gauge hit 960-970 degrees

As I was doing Autokhana, it was a quick bursts of under 1 min to 1.5 mins.

Then find (read fight for) the shadiest spot and cool down

Good to see similar numbers from a similarish setup - Assuming the 950+ you've seen was peak and very short burst, and that track or dyno pulls are closer to 900C?

Where were you running the sensor? We ran between head and turbo in runner 2 or 3 cannot remeber which.

[mx52nv]

Yes Sean, most of the time EGT hovers around 900 degrees for both track or dyno runs (in normal 20-30 degree ambient temps). EGT sensor was fitted on the 'dump' pipe or down pipe. There was a reason for this at the time but my memory fails me.

I think it was because of the ceramic coated cast manifold...

[Steampunk]

sweet caesar's ghost!! 900deg Celcius and over!!

The reason why I asked is because my wideband controller is giving me bad readings, and after checking over the manual it states that I shouldn't mount the O2 sensor where temperatures will reach 500deg C.
I'm doing a troubleshoot and whenever it gives me bad readings, it's after either a hard mountain run, or track-day.

Ok, Sean, Les... not that I'm doubting you guys, but your temperature readings are in Celcius and not Fahrenheit?

[ampz]

That is affirmitive for celsius readings.

I have a narrowband o2 bung about 20cm from the outlet flange on the dump pipe.
I borrowed an egt probe for about a month, after the initial tune on the car.
Temps there (mostly road tuning and spirited runs) ran around 450c with peaks of 840c under a max boost of 13 psi (small t25 turbo).

The only thing i had to plug the hole back up is the original, very burnt o2 sensor.

My wideband is about 4 inches n front of the cat converter and runs fine. It's an LC-1 and hasn't given me false readings yet (except when my dump pipe comes loose)

[Steampunk]

My wideband is about 4 inches n front of the cat converter and runs fine. It's an LC-1 and hasn't given me false readings yet (except when my dump pipe comes loose)

I have an LC-1 too and am MegaSquirting like you

My 02 sensor is situated on the 3rd primary pipe of my extractors, approx 28cm away from the exhaust flange.
So me thinks I've murdered me 02 sensor, you thinks too?

It's not that bad as I'm running open-loop 100% of the time now as I have my VE tables where I want them and the car runs faultlessly.

[ampz]

if it is fine for a while, but starts giving you errors when hot, it may just be overheating.
make up a heatsink for it and see how you go. (just get a flat piece of copper/stainless/mild steel and drill a hole big enough for the sensor threads, then use that like a gasket but bend the edges up)

28cm is a fair way away from the head. and if it's only freaking out after track time, my guess is it's heat soak.

[Sean]

Yep, celcius not F

[manga_blue]

Just for comparison with an non-turbo NA8 motor, Andrew. Mine has run up to dark red near the O2 sensor, which means 600-800C.

[Steampunk]

Thanks for the replies fellas. I am now almost certain that I have killed the O2 sensor, and/or the LC-1 itself.

Ampz, I wish it was as simple as you mentioned but its not, the LC-1 is still on the blink.

After trawling the Miataturbo and Innovate forums, this is not uncommon.
Way to go Innnovate... let's make a product that should withstand high-heat be susceptible to high-heat.

[mx52nv]

Yes my EGT is in degree Celsius.

Pity about the Innovate sensor

My 9 year old APEXi sensor still works fine

[ampz]

isn't it a bosh replacement sensor?
I'm pretty sure that was one of the reasons I went with it, because the sensor was realtivelly inexpensive to replace, around $60?