Egt q:

[Directconnection]

Sold my EGT setup (with new probe/leads) 2 weeks ago and the new owners are getting real low EGTs.

They are running 17psi on a stock garrett and also running +20s. Their fuel pressure was at 80psi and saw 1300 egts, and then cut it down 76psi and still 1300 egts. I hope that their base isn't 76psi....

I don't know where their egt probe is placed or if they cut the leads..... but they didn't see any difference in temps. (maybe because it's waay too rich right now?)

Should they be still 55psi base with the +20s... or do they need a tad extra base like they are running to be safe around 1500 at 17psi?

They are wondering if there's an issue with the gauge, but it should be fine.

[cordes]

They would need less FP to even out the higher flow rate. Although many of the cals, especially the MP ones can run the +20s fairly well. If they are running the FP which you've listed even with boost that's too much for a stock cal on +20s.

At 17PSI with too much fuel I bet you could run enough timing to get some low EGTs too.

[Directconnection]

Yeah, that's what I thought... but *I* don't want to make tuning suggestions on someone else's vehicle, especially if they are running a ported head and FMIC (but don't think so) And I don't want to tell them to lean it out if there is an issue with my former egt gauge, which I don't think there is. New probe and terminals that were not shortened when I shipped. They'll probably chime in here with their engine buildup specs soon.

[cordes]

Yeah, that's what I thought... but *I* don't want to make tuning suggestions on someone else's vehicle, especially if they are running a ported head and FMIC (but don't think so) And I don't want to tell them to lean it out if there is an issue with my former egt gauge, which I don't think there is. New probe and terminals that were not shortened when I shipped. They'll probably chime in here with their engine buildup specs soon.

I've read that if you get too much higher than 55PSI static it starts to be very hard on the injectors. That's something I would be concerned about.

[Directconnection]

Well, if they are 76psi at 17psi boost then they are only 4psi over....

[cordes]

Well, if they are 76psi at 17psi boost then they are only 4psi over....

That's probably not a huge deal I wouldn't want to run them the 8PSI over from the top end of the numbers you posted though. I've read it gets strenuous quickly, but I haven't heard of any real world failures either...

[zin]

EGTs can bite you, simply because they can be effected by timing as well as fuel. A plug reading would be the best way to back up the diagnosis, but a wide band would also let you know if it really is rich or just retarded timing... But it still isn't a replacement for a plug reading...

Mike

[Directconnection]

EGTs can bite you, simply because they can be effected by timing as well as fuel. A plug reading would be the best way to back up the diagnosis, but a wide band would also let you know if it really is rich or just retarded timing... But it still isn't a replacement for a plug reading...

Mike

I am hoping he posts in here as everyone's input could help him diagnose his tuning issues, or if it's his EGT not reading right. (it might not be installed in an optimum spot, or terminals shortened, or..)

[ShelbyZD]

We will check the plugs tomorrow. Also, we can only get 91 octane here. :(

Car is a 87 Charger with an A-555, Mopar GLHS LM, 88 Turbo 2 motor with .20 over forged wisco's, ported exhaust manifold (presumably by spoolboy), +20% injectors, cone style air filter, opened up stock T2 exhaust (no cat, pipe cut before it turns to smaller size by gas tank), valve job as described on the dodge garage. 17psi and 80psi total fuel pressure. Runs rough at idle due to fuel. Timing stock @ 12 deg.

Anyway, at WOT and 80psi EGT didn't go over 1300. Turned down to 76psi and 72psi.. no change. As as last ditch effort fuel pressure was turned down to stock T2 fuel pressure and there was still no change. It may be worth noting that under normal driving conditions EGT temp did get into the 1400's.

Probe is in no 4 runner and approx 1 1/2" away from the head. Thanks for any help. :)

[cordes]

If you want to test the EGT try taking out 4-5 degrees of timing with the dist. That should be good for a higher EGT for sure.

[Directconnection]

Can't he just test it with a voltmeter? Wouldn't a very small voltage to where the probe connects at the gauge make it work? I see it does go over 1400 degrees at cruise.

Dale, did you guys have to lengthen the probe's wires at all? (or shorten them)

[shmedley]

Maybe the thermocouple wires are reversed?
When you switch them up they do some funky things

On thermocouple wire the red wire is the negative
If it is a Type K thermocouple (Yellow and red wires) the red wire is magnetic


Also it's usually too low of a voltage for a regular DMM to read

[Directconnection]

Maybe the thermocouple wires are reversed?
When you switch them up they do some funky things

On thermocouple wire the red wire is the negative
If it is a Type K thermocouple (Yellow and red wires) the red wire is magnetic


Also it's usually too low of a voltage for a regular DMM to read

It should be a type k thermocouple.