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perversity
01-05-2004, 11:21 PM
I recently installed a digital EGT in the 2nd exhaust runner, about 3" from the head. I am seeing about 535 at idle, 760 at 3000 rpm with no boost when cruising on the highway and between 875 and 931 WOT full boost.

(I know that's high, I need to do some more A/F management)

Has anyone else installed an EGT guage? If so, where is it and what sort of numbers are you seeing?

howiEVO8
01-06-2004, 12:51 AM
what's EGT?

ItsStockOfficer
01-06-2004, 02:27 AM
Exhaust Gas temp....and 931 is a bit too high, what mods does the car have? I try to hit 890c at the top of third.

howiEVO8
01-06-2004, 04:51 AM
does it make a difference is performance and can you control this?

ItsStockOfficer
01-06-2004, 11:25 AM
Yes and yes...The EGT's do not affect performance theselves. The amount of ignition timing(mostly) and the a/f ratio(to some degree) affect EGTs.

You can control EGT's by making your car leaner or richer.

perversity
01-06-2004, 05:52 PM
what's EGT?

As the title of the thread is Exhaust Gas Temps, I would have thought it was pretty self explanitory....

But to anwer your ?, Exhaust Gas Temp.

EGT gives you some indication of how rich or lean your fuel mixture is. If it is too lean then you see high temps. High temps = blown engine.

The reason I put in the EGT is to get an idea of how safe my setup is, as my mods are very similar to a lot of other people's mods.

I'm running HKS RS intake, 3"AVO turbo-back and SAFCII with Buschur settings on 91 octane.

leaveit2bevo
01-06-2004, 06:39 PM
I wonder if it has anything to do with the piss water we have in cali.

howiEVO8
01-06-2004, 07:19 PM
you mean the 91 octane? okay this is a lil bit off topic maybe...but if lets say i take a trip into oregon or where not,
and they have like 93 pump or higher octane, will it be okay to put that in my car? and if so, for what duration?

leaveit2bevo
01-06-2004, 09:53 PM
you mean the 91 octane? okay this is a lil bit off topic maybe...but if lets say i take a trip into oregon or where not,
and they have like 93 pump or higher octane, will it be okay to put that in my car? and if so, for what duration?

Yes its fine to run 93 its way better than 91, your car will run smoother and have more hp. When we go to the track we mix 100 and 91 octane to make 94 so the car will run the best.

ItsStockOfficer
01-06-2004, 11:41 PM
It would run the best on pure 100 octane, leaned out, and with more boost....

leaveit2bevo
01-07-2004, 12:11 AM
100 octane will make no difference on the stock ecu.

ItsStockOfficer
01-07-2004, 12:45 AM
The stock ECU will pull timing if it detects knock. The stock car can easily knock on 93 octane. Get a logger and check.

If you have a boost controller, then you can get a much larger benefit. On the stock ecu you can turn the boost up. If you have a fuel controller you can get a even larger benefit, you can lean it out.

By stock ecu what are you referring too? I said turn up the boost and lean it out...That imply, at bare minimum, an SAFC and a MBC. Thats the same combo RNR is making 500 whp on 110 octane on a stock ecu with.

Even with a stock EVO ecu, no fuel control and a MBC you can safely run 23-24 psi on pure race gas...

turbrodude
01-21-2004, 11:18 PM
Sounds like you need to turn that AFC up. Just cuz it has Buschur settings doesn't mean you should never touch it. Every car is slightly different. If you're seeing 930 EGT's, the motor is knocking and the ECU is pulling timing to protect it. Add fuel, run higher octane fuel, or turn down the boost.

Blak94GSX
02-03-2004, 06:11 PM
Anybody running an EGT gauge on an otherwise stock fuel system car?

Blak94GSX
02-03-2004, 06:15 PM
you mean the 91 octane? okay this is a lil bit off topic maybe...but if lets say i take a trip into oregon or where not,
and they have like 93 pump or higher octane, will it be okay to put that in my car? and if so, for what duration?


Octane is the rating of how knock resistant the fuel is. The higher the number the more STABLE the fuel is. Water has a VERY HIGH octane rating, and highly explosive crap gasoline has a lower octane rating.

If you can find 93 or higher octane fuel the combustion temps will actually be lower and the ECU will add more timing to take advantage of it. Ultimately timing is where the power comes from, so the more the better.

It is a common mis-conception that higher octane fuel burns better or makes more power, when technically the opposite is true.