EGTs are too high!

[SilvrEclipse]

Ok, I know that not very many of you are familiar with the 420a but maybe I can still get some help. Ever since the car has been turboed the egts have been getting really high. According to 2gnt they shouldn't get over 1600. I am running stock injectors with a walbro 225 pump and 12:1 FMU. So basically my fuel pressure raises about 12psi per pound of boost. This should be good up to about 8psi when the injectors max. Anyways I always thought my high egts were caused by boost creeping to about 9psi and maxing out the injectors and running lean. I just installed an external wastegate and is set at 7psi. Also I have a voltmeter on my o2 sensor. (I know this is not accurate but it does let me know about where my fuel is) So when I go WOT in higher gears like 4th and 5th mainly the egts slowly creep to 1600 and then right past that I let off. Tongiht I did a 4th gear pull from about 50 and around 115 i had to stop cause the egts where to high. This pisses my off so much that I cant run the car WOT to long. I have 1 stage colder plugs in it, should I go ever colder? My o2 sensor is around .97-1volt so im running rich. Any help will be appreciated.

[gthompson97]

I don't get it. Are you leaning out or not? You said you thought you were but then said you were running rich, I'm confused. Are you getting any knock?

[blk_srt]

First off it is impossible to know if your running rich or lean with a narrow band O2 sensor. If its working correctly it will go rich and lean and back and forth. Anyway high egt's are caused by running lean. Get yourself a wideband and figure out exactly what your afr is

[SilvrEclipse]

Sry if that was confusing, Im running rich now. When at WOT the narrowband o2 sensor settles down bc the ECU goes into closed loop mode.
I dont have a logger so I dont know if I am getting any knock. I would love you get a WBO2 but Im not exactly rich so thats kinda hard.

[gthompson97]

I would definitely pick up at least a logger asap, you could be knocking like crazy and nearing the end of the life of your motor. What about something to control those injectors? I think you should turn down the boost until you can safely figure out what's going on (most likely running way lean) and just keep off the gas so you don't blow your motor. I'd pick up a logger, SAFC, and some bigger injectors. When you can, definitely pick up a wideband so you can fine-tune your setup.

You say you don't have the money for a wideband but you're running on the verge of blowing up. I'd eat my money right now to keep your motor safe than have to throw out $1000 in a month when you've blown that motor to pieces.

[SilvrEclipse]

I turned the boost down to around 5psi. I am going to see what I can do tomorrow with it. I really dont think I am running lean. The cars runs great and pulls really strongs. Just when at WOT for long periods of time it starts to heat up. It has gotten better than it was so that is a good thing.

[spyderturbo007]

Originally Posted by SilvrEclipse

So basically my fuel pressure raises about 12psi per pound of boost. This should be good up to about 8psi when the injectors max.

What size injectors are you running? Also, I don't know about the N/T's, but your FP should raise in a 1:1 ratio with boost. For example, a 2g turbo runs a base pressure of 43psi. As you enter boost, for every 1psi of boost generated, the FPR will increase FP by 1psi. So at 20psi of boost, you should have a FP of 63psi.

Anyway, high EGT's are not just caused by a lean condition. A very rich condition can cause high EGT's also. You can actually encounter a point where the mixture is still burning as it's leaving the combustion chamber.

[SilvrEclipse]

Im running stock injecters. Thats why my fuel pressure rises so much with boost.

[BoostedSpyder]

so you are saying that your fuel pressure is around 96psi OVER the stock FP @ 8psi of boost?
seems a bit high, to say the least.

i'm no 420a expert, more of a has been 420 expert, much of which is knowledge regarding water systems, you know.

i would say you are very much on your way to a blown engine if you don't do some serious logging to see where you really are internaly.

check this thread if you have not already, it has been hacked to shreds, but there still may be some interesting stuff in there...

link

[SilvrEclipse]

Yea that thread sucks. I changed the plugs today and at 5psi it ran good. EGTs settled at 1550. We bumped the boost back up to 7psi and slowly the temps creep up to 1600 and settle right about it. Yes my fuel pressure is extremly high and this is the way most 420a turbo systems are set up so I know this works.
My motor isin't that good anymore so I plan on rebuilding it this summer but I want every straightened out before then. The car runs extremely well but those high temps make me nervous. What do you think about a colder plug. I have BKR7e in it now, is there anything a little colder than that.

[BoostedSpyder]

well then i really don't know shit about 420a's then. that seems crazy high for FP. that is like well over 100psi. and EGT's on a 4g63 are like 900 = super hot.

ah well.

[SilvrEclipse]

I think it has something to do with the 420a being higher compresion. Most people shoot for around 1500 to 1550 for a good tune so im not to far off. Mine just rise a little to much.
Can anyone tell me a plug 1 range colder than the BKR7e??

[gthompson97]

I think you should be more set on a logging device than a colder plug. With the colder plug you're still playing the guessing game. My advice: Get a logger, tuner, and afpr.

[vanilla gorilla]

Originally Posted by BoostedSpyder

well then i really don't know shit about 420a's then. that seems crazy high for FP. that is like well over 100psi. and EGT's on a 4g63 are like 900 = super hot.

ah well.

As in 900 u must mean celcius. I think SilvrEclipse s referring to fairenheit temperatures.

SilvrEclipse

SilvrEclipse:

My EGT's on my turbo 4g64 also peak around 1550 or so. I think this is about right, but it scares me, lol. I'm going to get a wideband just to make sure though.

[BoostedSpyder]

yes degrees C. sorry for the mis info.