Optimal 2F engine EGT's? (1 Viewer)

[Beehanger]

Hey guys,
Installed an EGT gauge on my rig as a precaution for tuning.
Curious if anyone has done this on their fj60, and if they have an approximate reading that works for them. I installed my probe right beneath the header (which I'm sure changed the reading slightly)

Happy New Year!

Dan

 

[garfieldthecat]

EGT or AFR meter? I think the AF ratio is supposed to be 14.7. Not sure on the exhaust gas temp though. I thought those were mainly used on diesels? There's a thermosensor in the catalytic converter that reduces its resistance as the cat temp gets to around 1700 degrees I believe. Some of the supposed high heat coatings for exhaust parts are rated to 2000 degrees, so maybe 1700-2000 degrees is the upper limit of what you should read? I don't know how insight into your exhaust temp would assist with tuning though.

 

[FJBen]

EGT usually is only used on diesels. I would think AFR is much more useful for tuning a gasser.

 

[Rgill]

EGT on a gas engine? I would think reading the plugs or using a AFR gauge is better data for tuning. If you have a smog pump then really only the plugs can give you good information. Since the smog pump adds air, the AFR can not read true fuel mixture data. I installed fuel injection which uses a oxygen sensor. AFR gauges also use a oxygen sensor. I mounted my O2 sensor on the down pipe about 8 inches below the upper flange. Fuel injection instructions recommended as close to the exhaust manifold as possible. Oh and I am de-smogged, no smog pump.

 

[Beehanger]

Part of the reason is if it gets above a certain temp I'll know it's likely going to burn a valve because its running so lean.

It can still run lean without hte engine overheating, but bust a valve in the process. Correct? that's what was explained to me and half the reason I did it.

 

[bj70bc]

you need afr wideband more importantly, tells you if youre lean in a much better way

 

[Beehanger]

you need afr wideband more importantly, tells you if youre lean in a much better way

Would a cheap one off amazon suffice for this? I've heard AFR run upwards of $500 but maybe the guy I was speaking to was talking about a high quality one. Not sure the nuances here.

Found this one online. AEM 30-0300 AEM X-Series Wideband UEGO AFR Gauge Kit - https://www.aemelectronics.com/products/dashes_and_gauges/wideband_gauges/x_series_wideband/parts/30-0300?gclid=CjwKCAiAqNSsBhAvEiwAn_tmxTUCWFxamC4JrQ3Dxv1t43aRHWpjbB0URbKU1K4dtpjWCXkM-NwpPRoCkbMQAvD_BwE

 

[bj70bc]

that should do the job, but unless youre turboed you shouldn't really need a gauge to tune as you shouldnt be running into engine destroying detonation problems
what exactly are you doing in terms of needing to tune it

 

[Beehanger]

that should do the job, but unless youre turboed you shouldn't really need a gauge to tune as you shouldnt be running into engine destroying detonation problems
what exactly are you doing in terms of needing to tune it

I'm having issues with rough idling, and vacuum leak problems, all related to an aftermarket chinese carb im using. Wish i had rebuilt my Aisin instead but im desmogged and a buddy had this one. can't determine if my 11 hg vacuum reading is becasue of improper tuning or a vacuum leak.

I want to be able to drive it as I no longer have shop space to work on it after this week. I'm hoping a guage can tell me if im harming the vehicle even driving it a 10 mins to work everyday improperly tuned. I have two threads going on the issues Im having, if you care to weigh in.
Carb leaking fuel - https://forum.ih8mud.com/threads/carb-leaking-fuel.1329502/#post-15301010

Dear mother of God. Top of intake manifold not flat.

Gentlemen, I’m noticing post engine rebuild and reinstall I’ve got myself in a big pickle right when I thought I was at the finish line. ! I’m beyond my scope on knowing how to protect fix this one and seems like I have one shot at it. The Intake manifolds carb surface isn’t flat. I took a wire...

forum.ih8mud.com

 

[bj70bc]

you probably dont need an afr gauge, sounds like you need a better (or working) carb.
once the carb is working, afr and egt will be a moot point,

 

[FJBen]

you probably dont need an afr gauge, sounds like you need a better (or working) carb.
once the carb is working, afr and egt will be a moot point,

Exactly. That egt won’t help with the tuning you are needing. Save money and just buy a new carb.

City racer has one for $325 I’ve heard good things about that Japan made one. . Using a crappy Chinese carb is going to have you chasing your tail.

 

[Beehanger]

Exactly. That egt won’t help with the tuning you are needing. Save money and just buy a new carb.

City racer has one for $325 I’ve heard good things about that Japan made one. . Using a crappy Chinese carb is going to have you chasing your tail.

agreed.

 

[timexlost]

EGT probes are a good way to tell if you've got proper AFR based on the temps shown, it's not just beneficial for diesels. You'll get the same findings with either method, a wideband O2 is easier though. EGT probes are really beneficial in fuel injected applications with a probe in each exhaust runner and a good standalone ECU so you can monitor each cylinder individually and adjust injectors accordingly.

I'd start with a quality carb and go from there.