High EGT Question

[Jerryl]

Here is a screenshot showing the AFR and LV8.
Not sure why the O2's dropped while LV increased.
This "spike" however did not affect EGT (???)

Appreciate the feedback.

 

[SloGN]

1571 @ 800 rpm was this after a WOT blast on the highway? or is this sitting and idling with the a/c for a bit.


If you just idling and it's that high i would check to see if that EGT gauge/coupler is working correct.


from what i have learned that when doing a lean cruise after 14.7 the EGTs tend to get coller due to there is not enuff fuel for it to get hot with. Also the leaner the mixture is @ low load the more timing you need to get anywork out of the charge. i run my fast system @ 15.9-16.2 AF with timing around 44-45 degrees.


Also like so other guys have stated your a little to rich on the alky. the stoich on methanol is 6:1 compared to 14.7 on gas. What i have noticed is when using alky you would s try and target your AF about .5 richer than on gas as a good starting point. When i used to run my car on alky @ 20 psi of boost my AF was 11.8 with no issues.

 

[Jerryl]

1571 @ 800 rpm was this after a WOT blast on the highway? or is this sitting and idling with the a/c for a bit.

If you just idling and it's that high i would check to see if that EGT gauge/coupler is working correct.

Also like so other guys have stated your a little to rich on the alky. the stoich on methanol is 6:1 compared to 14.7 on gas. What i have noticed is when using alky you would s try and target your AF about .5 richer than on gas as a good starting point. When i used to run my car on alky @ 20 psi of boost my AF was 11.8 with no issues.

The posted snapshot was comming "of idle", at a light (50 seconds idle)

Can you explain what you mean by "gauge/coupler"?
What I use is the EGT probe (K-type), EGT signal amplifier, and Power logger.

Regarding AFR - I Don't know.
I would think that AFR depends a lot on the amount of alky you are spraying vs fuel being injected.
For a 10% fuel replacement, you should have a different target than 30% replacement.
Plus, every car is different, and this is a HA.

Appreciate the feedback!

 

[Jerryl]

A thread I recall reading on AFR with 93/alky :wink:

http://www.turbobuick.com/forums/al...w-does-methanol-affect-wideband-readings.html

 

[SloGN]

A thread I recall reading on AFR with 93/alky :wink:

http://www.turbobuick.com/forums/al...w-does-methanol-affect-wideband-readings.html

yeah i have read that too.


some say about a point lower and some say tune it as it was gasoline. I myself found to make it about .5 richers and it seems to be ok. course my car on straight 93 octane when i had the factory ecm would want the 02's to be in the 800's to the 830's for the best et/mph @ the track.


well i have been working on E Singer on his hot-air and i think we have his target AF set for 10.9-11.1 on the alky @ 25lbs of boost. i can't remember but he has made 303hp on a mustang dyno. stock heads and cam.

i have been around the HA for a little bit and understand their needs.

 

[cool 84]

Do your headers glow during normal cruise? Mine have a very low glow from driving around if you look at them at night with no light around but you have to really look for it. If your EGT guage is correct, they should be bright orange when you pop the hood at night.

 

[Jerryl]

Do your headers glow during normal cruise? Mine have a very low glow from driving around if you look at them at night with no light around but you have to really look for it. If your EGT guage is correct, they should be bright orange when you pop the hood at night.

I have never seen any glowing, and after 5 days of scratching my head and some fabulous feedback on this board and from some experts, I have concluded that the reading is incorrect.
The question is "why the error"?

I use a Zeitronix WB set-up and this unit has the ability for a "direct plug" for the EGT probe, thus eliminating the amplifier.
This should give me an idea what is going on - I will get this resolved with my "plan". (Ahhh, the process of elimination ... )

yeah i have read that too.
some say about a point lower and some say tune it as it was gasoline. I myself found to make it about .5 richers and it seems to be ok. course my car on straight 93 octane when i had the factory ecm would want the 02's to be in the 800's to the 830's for the best et/mph @ the track.

well i have been working on E Singer on his hot-air and i think we have his target AF set for 10.9-11.1 on the alky @ 25lbs of boost. i can't remember but he has made 303hp on a mustang dyno. stock heads and cam.

i have been around the HA for a little bit and understand their needs.

SloGN, Very cool!
318HP (I think) on stock heads and cam - Who says alky does not work?
ESinger is on top of it!!

Actually ...... after litterally hundreds of runs, the car runs best at 10.9 - 11.1, but I get a hint of KR, so I target 10.7-10.9 on the WB, which is EASY with the TurboTweak Technology! (Shameless plug )
I will say this; There is a BIG difference between 10.7 and 10.9!
I also ran it very rich for this experiment, but it did not affect the EGT's!

Thanks for the feedback guys!

 

[turbo6x2]

Jerryl I know when my probe finally cooked last year on my EGT meter it read super high. Might want to get a new probe for it. I have the address here somewhere I think. They are only supposed to be submitted to like 1500 degrees at a time and we do tend to go higher then that. I bought an extra one. A friend told me where to purchase it from and once we installed the new probe better readings.

Right now with everything tight from freshened motor I noticed my EGT readings were 900-1100 this weekend getting break in miles in. This with temps in the low 80's.

Hope you post what you find out.

Jamie

What's the NB Sensor by the way?

 

[Jerryl]

Jerryl I know when my probe finally cooked last year on my EGT meter it read super high. Might want to get a new probe for it. I have the address here somewhere I think. They are only supposed to be submitted to like 1500 degrees at a time and we do tend to go higher then that. I bought an extra one. A friend told me where to purchase it from and once we installed the new probe better readings.

Right now with everything tight from freshened motor I noticed my EGT readings were 900-1100 this weekend getting break in miles in. This with temps in the low 80's.

Hope you post what you find out.

Jamie

What's the NB Sensor by the way?

Jamie,
The NB is a purple wire GM unit.


------------------------------------

Here is what I found;
The probe is ungrounded.
Connected the EGT leads to a Fluke and Crafsman with a "K-type Adapter"
Reading; 780F @ Hot idle.
So, it makes me conclude that the EGT adapter is off.

So, we need a "LARGE" adjustment added to PL for the EGT, unless there is another solution.
Than again, I have serious doubts about the "linearity" of the amplifier since PL indicates ambient +10 (cold) and around 1400F (hot) idle.
The Fluke indicates 95F ambient (which is correct) and 780F hot idle.


Edit:
I have never read or heard anything about the "Old adapter", so I belief it is the "new revision" unit that is off, WAY OFF!

 

[cool 84]

I have nothing to contribute except to say that I installed the Powerlogger in a friend's 87 GN and wow. It makes me feel like I've been wasting my time all these years tuning blindly.

 

[BRAD_PADGETT]

I have nothing to contribute except to say that I installed the Powerlogger in a friend's 87 GN and wow. It makes me feel like I've been wasting my time all these years tuning blindly.

Just imagine what you can do with a wideband o2 sensor hooked up to the powerlogger and the new TT WB chip. Adjust A/F ratio accross the shift pattern. It works. Good luck- Brad

 

[turbo6x2]

Having that much information really makes a huge difference in what you can do with a turbo car.

 

[Jerryl]

Borrowed an older style FT EGT adapter from Steve W. installed and took the car out for a ride. (THANK YOU STEVE!!!!)

Cruise @57mph, AFR 14.4, EGT’s 1080F, 37 timing
Saw EGT’s around 1570F, 10.85AFR, 15.2 PSI, 16.6 timing (with PAC @ 6)
Hot idle EGT settles around 890F
GREAT numbers IMO.

My suspicion has been confirmed, thanks to the assistance from Steve!

 

[Boost231]

wow missed this post. glad u figured it out. i figured it had something to do with the probe before u posted it.

 

[Jerryl]

Update

Since Ya'll were wondering
Ended up with this unit.
EGT Signal Amplifier