Louis Gigliotti

With compression that low, I can see it doing that.

I know you have experimented with timing, but have you tried some outrageous numbers? 40? 45?

5 Liter Eater

Last night night I idled it for ~10 min with timing locked at 55 and they were faint red. If I had driven it I'm sure it would have been brighter red.

Louis Gigliotti

Faint red in the dark? It's much easier to see them glow, at night.

Compression that low will have an incomplete burn.

Try leaning it out, and make sure your injector data is spot on low pulse scenarios can be a bitch with bad/wrong data

5 Liter Eater

Yes in the dark. I don't think it would be very easy to see in the light.

The wideband is showing ~stoich (pump gas) and fuel trims are small corrections. I can put it in open loop and command leaner as a test.

Blackonblacksls

Well wouldn't an incomplete burn give a false reading on the wideband?

I thought I remember reading unburned fuel gives a richer reading than it actually is??

JDS99

The 02 sensor only reads oxygen content present, doesn't matter how much fuel is in there. But the more incomplete the burn is, the more leftover oxygen is present in the exhaust gases hitting the sensor. This will make it think it's leaner than it is, and closed loop trimming on stock ecm will add extra fuel. Gets worse the more overlap there is as well obviously.


Bill, pulled up a quick search. Here are some temp references to color:
degC -- degF -- Color

400 -- 752 -- Red heat, visible in the dark
474 -- 885 -- Red heat, visible in the twilight
525 -- 975 -- Red heat, visible in the daylight
581 -- 1077 - Red heat, visible in the sunlight
700 -- 1292 - Dark red
800 -- 1472 - Dull cherry-red
900 -- 1652 - Cherry-red
1000 - 1832 - Bright cherry-red
1100 - 2012 - Orange-red

It's more common for the import guys to run egt probes in the runners. Can find a ton of them posting up temps anywhere from 750-1000degF idle temps and higher cruising temps. Since your manifolds aren't ceramic coated, and are wrapped, I still believe this is why you're seeing the red.

Due diligence and checking everything out doesn't hurt a damn thing, just throwing this stuff on here for reference.

5 Liter Eater

that's good to know. If that's the case then I could totally see it reaching those temps/colors in the dark. Makes me feel a little better.


I'm going to get another IR temp gun dealy to ~verify temps but an EGT would really be nice. So would a back pressure probe pre-turbo. I'm still going to do a leakdown on #1 with the rockers on at TDC.

schpenxel

Unburned fuel shows up as lean. Sounds backwards.. but oxygen sensors are going to sense, well.. oxygen, not fuel.. so extra oxygen, even with extra fuel = lean on O2 sensors.

Or I could be wrong, but that's my understanding of it.

slow ride

I noticed in my old DSM back in the day I would run 650-750 C egts at light load highway speed and the manifold was a noticeable red glow. The cars are running 14.7 ish so the exhaust will get hot. Even cooler was the drop in egts from going to a larger turbo. I'd say that was a 50-100C drop in egts

user_name

When I had a ttix kit the the only time I ever noticed a glow was after racing, and it wasn't anything close to being orange. I know I checked in daylight before bc I remember trying to check plugs on the dyno. HOT but not very red.

5 Liter Eater

So my IR temp gun came in yesterday. Not sure what to think, LOL.


After ~10 min of idling at ~30' timing in the garage, I could barely see a little hint of red on the turbos:



After a ~10 minute "non-spirited" drive, very light load, they were bright as in the pictures posted earlier.



So while the temps don't seem "outrageous" they're not great either and I don't know whether or not it's a problem...


I'm close to taking things ~apart to validate ignition timing and valve events. Before I do that I think I'm going to remove the wrap and blanket from one side and see if there is a difference in color and/temp.

Arctic Vette

Did you pull plugs to check for lean or rich condition? I had a TT 350Z prior to the Vette and never had glowing, ever. As already stated it could be thin walled headers too, but timing off is my guess.. Id triple check the cam position and damper timing for pinpoint accuracy. Hope u get it fixed

5 Liter Eater

So we did a similar test on inspector12's car last night. Started it up and let it idle for ~10 minutes. By the end of the test the manifolds averaged ~550-575. His manifolds are coated and wrapped and he's running corn. Couldn't get to the APS turbos with the heat gun. But these numbers are similar or even a bit higher than my first 10 min idle test.


Starting to think its a non-issue.

user_name

Time to hit the dyno and read some plugs!

Ultrasport05

Bill, did you have the hot sides and manifold ceramic coated? I feel like that's a better route to take than the heat wrapping. From what I've read in here I'm with you and starting to think its a non issue but not as familiar with turbo set ups as some on here.

5 Liter Eater

No none of my hot side parts are coated. But if anything I kind of feel like no coating and no wrap and no blankets would allow the most heat to be rejected from the manifolds and turbos. I'm tempted to take the wrap and blanket off one side and do a side by side test. But I don't feel like yanking the manifold to re-apply wrap should I decide to.

Ultrasport05

Gotcha. I figured you'd want to keep the heat in the turbos but like I said my knowledge on turbos for these cars is limited

inspector12

Yeah that was a little bit of a surprise on my temps, but mine don't glow either lol! But not sure what to think. Either way Bill I wouldn't go pulling of any wrap as I don't care what the readings are the wrap is needed to keep everything else around your car cool. Mine haven't always been wrapped or coated, but never glowed and always been min of 427ci. I'm sure they do when beating on the car, but I've never been able to see it even after making a few hits and popping the hood to let it cool down and we looked just for curiosity sake. Maybe nothing is wrong and it just the type of casting material that TTIX is using???? Thanks for the help yesterday Bill.

ajrothm

I agree.. Leave the wrap on it... Keep it from cooking everything else in the engine compartment.

If it runs well, plug readings are safe and the tune it good, I'd let it eat..

I do think it's odd the pipes/turbos get that hot at idle/no load but... Since you verified the timing is correct with a light, not much you can do.

Get the afr correct, read plugs (fresh plugs), maybe put it on E85 and forget about it..


As I mentioned earlier, my header radiant heat is WAY worse then it was before the rebuild, and that's with a thick pure ceramic 2500* coating.. Feels like opening the oven door every time I open the hood....only difference is I have a lot more overlap on the cam this time. We did degree the cam in as well and it was within .5* of the required intake CL.


FWIW, on my turbo bike, I don't have the header or turbine housing coated, it's an 8.8-1 comp motor and stock timing tables and it's never glowed the pipes at idle.. Only one time did I EVER see it light the turbo up and that was on the dyno at 30 psi boost....(435 rwhp), never saw it do it again. Low compression is not causing this issue.

ajrothm

Bill,

Out of curiosity, I just shot mine with the temp gun. This is after a 10 min idle only.

1: 772
3: 815
5: 803
7: 815

2: 759
4: 792
6: 790
8: 780

This is way hotter then I used to get with the small cam.. And this is with much better ceramic coating. It's MUCH noticeably hotter under the hood and around the headers then before.

Only thing I changed is the cam and header coating.

It used to be like 600s.

Just FYI.