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Campbell
02-03-2008, 02:06 PM
I just got another car that has an exhaust temp gauge in it. The thermocouple is in the #1 header tube.

I have no idea what exhaust temps should be for a 8v, 1.8L - is there a baseline I should be looking for? does the type of gas I use affect it? just how to you interpret the readings..

thanks

JeffYoung
02-03-2008, 09:26 PM
ITS TR8, 3.5l V8. 1450 consistently under WOT. I think that is too hot.

Ron Earp
02-03-2008, 09:40 PM
If I had the EGTs on the hot cylinders and they were mounted pretty close into the port and done right I'd be shooting for 1400-1425 F range.

My EGTs are on the wrong cylinders for my motor, #1 and #6, are mounted a bit further away from the port than they should be, and I shoot for about 1325-1350 F, no more than that as I know the hot cylinders should be running a bit leaner due to intake design (carb motor). Clearly a guesstimate on my part but I need to be safe and not toast a motor. Still might be unsafe too since I'm not on the right cylinders....

If you want to be fairly safe 1300-1350F.

YMMV.

racer_tim
02-03-2008, 10:11 PM
1,300 to 1,400 is correct for a VW 1.8.

I've heard 1,325 is a good starting point.

rabbidmk1
02-04-2008, 12:00 AM
you got another new car?????

jlinfert
02-04-2008, 06:10 AM
1,300 to 1,400 is correct for a VW 1.8.

I've heard 1,325 is a good starting point.
The best starting point is to take the EGT out and throw it away. Use a wideband O2 to tune for 13.5 to 1 AFR . 12 to 1 will read 1350 to 1400 deg on an EGT and so will 14to 1. EGT is WAYYYY to slow to be worth a damn and as stated, way to inaccurate.

JeffYoung
02-04-2008, 09:12 AM
Generally agree, but have found it useful for:

1. Noting when one carb simply quick working (that bank EGT died). This lead me to a sticky float and probably saved a fire.

2. Noting whether carbs are in balance from a mixture perspective (not a plus on a single carb'ed car, I know).

3. Understanding if the car is running cool/rich or lean/hot in a general sense.

I do agree that the wide band is the way to go for getting a true A/F ration mix.

JimLill
02-04-2008, 09:47 AM
1350 is "standard" for a gasoline engine at optimum AFR

rmicroys
02-04-2008, 12:27 PM
I run Mikuni 44's 2.0l 8valve, 285 cam, about 12.5 AFR (wideband), runs around 1380 up the back straight at Mosport on good days.