I have an 87 T2 with the following relevant mods
intake
tid
tb mod
3" turbo back to hks titanium
starion fmic
walbro pump
safc
800cc secondaries

I have been using a AM A/F meter and with my injectors tuned to -12% across the board I am still running 2/3 into the rich side, but dont have the ***** to tune out more fuel yet. The egt is an autometer up to 1600F, and it is tapped right behind the o2 in my racing beat downpipe. I should keep leaning it out till I see what temps under full boost on the egt? Thanx guys

 

Unfortunatley EGT is not that accurate of a tuning tool.
Some engines run hotter than others, but as a general rule I would shoot for no more that 900Deg.Celcius. I am real fond of 850.


The other thing is the placement of the probe on your EGT. The further downstream you have it the lower temps you will see. This is not accurate. an ideal location would be somewhere in the manifold.

 

yeah, you want the probe mounted as close to the turbo as possible for the best readings. but as far as the temps to tune to, about 850 c is pretty good like Ranzo said. the rotary runs hotter than most other engines so thats pretty warm.

 

Ranzo..Why do you say that EGT gauge is not good for tuning..i thought there in JAPAN that they preffer the EGT rather than the misleading A/F gauge.

 

yeah I aleays hear that the afisnt as good a tool as the egt guage.? What do those temps translate to in F?

 

0 F = -17.78 C
5 F = -15 C
10 F = -12.2222 C
100 F = 37.78 C
500 F = 260 C
1000 F = 537.78 C

As you can see the only difference between the two is the absolute zero

 

I say its not that good because you have to correlate that temp to particular A/F ratio before it really means anything.

My first side port engine ran 900-920 deg no matter what I did, even if it was so rich it was puking gas. Adding a front mount intercooler dropped the EGT by about 40 deg but I just got so tired of looking at that gauge and it was always going to the same place.

I think if you had multiple probe points liksay for each rotor then you would be into something you could tell which rotor burns hotter and could indicate which injectors were good and so on.

 

What kinda temps are you seeing now?
EGT probes in the downpipe should run about 720&#176C at WOT.
http://fc3s-pro.com/TECH/MODS/EL/egt.htm for &#176F to &#176C equivalent.
http://n-xsi.com/HALTECH/tuning.htm


-Ted

 

A proper wideband A/F meter is not misleading, and that's what should be used for tuning. A/F gauges reading the car's O2 sensor, like EGT, should only be used as a guide to what your engine's doing, not for tuning.
Like Razno said, you have to correlate EGT to A/F (which is impossible to do accurately), so why not just measure A/F directly?

 

Ted straight up between what 2 temps should I tune to be between at WOT(in F)?

 

i have a greddy egt. the probe is mounted in my hks manifold near my hks turbo upgrade. the egt reads no more than 900C at wot full boost 4th gear. no pinging. i also have 850cc secondaries to back me up and no super afc. also, i dont think a 1600F autometer egt guage is good enuf. you need something that measures a bit higher. thats why i had to buy the damn expensive greddy one or else i would've got the autometer one.

 

It looks a little over 1300&#176F, so shoot for 1300&#176F sound about right.



-Ted

 

Holy cow, that must super rich!

 

After thinking about overnight, I think I was off by 100&#176C!&nbsp Oops!&nbsp I've reset the numbers to what they should be...


-Ted