Sup guys.
I searched every single post in this forum, and I cannot find an answer.
This is a problem related to low vaccum signal, and high EGT value.

I had this problem since I rebuilt my engine (2 months ago) and I mentioned about this before. but after 2 months, and talked to my mechanic, we agrees it's my timing advanced too much that it cause my EGT to get so high, and also vaccum to be lowered.

When at idle, my timing is mostly stayed at 2+ sometimes 4+.
When I touch the gas peddle (I am saying just normal driving, no boost, not hard accelerating), the timing will go up to 16-22+.
When I am trying to accelerate when I am going 50mph to 60mph (slowly also) my timing will shoot to 36+. if I do WOT, it's over 40+.

OK, I read 20 should be the value for timing advance when WOT. mine is double that. and even for LIGHT acceleration, my timing goes over 32 or more (advance)

All I changed from before rebuild to after rebuilt was, lower compression piston, that's all.

Is there anything tha tI can look for or adjust to change or fix the ignition timing of my eclipse??

Thanks guys.
As of now, my eclipse cannot go faster then 70mph unless I keep my EGT at 1500+ and of course I am saying flat road. if uphill, I cannot go faster then 60mph or 45mph if very steep. please help.

EDIT: I got the WBO2, and I got the MS standalone. But I really want to fix this problem before I install MS. and I cannot do Spark with MS right away anyway. so please help.

Gil

Anyone? someone please help.

Originally posted by gilee_8
I searched every single post in this forum, and I cannot find an answer.

Is that so?

http://forums.2gnt.com/dcboard.php?az=show_topic&forum=4&topic_id=79164&mode=full

As far as the timing, I'm not sure what max is in our cars, but I run 38* full advance in my cougar with 11.5:1 compression.

Hi, yes I read that post as well.
And I talked about this issue also.
I checked my timing belt timing 3 times already. they are RIGHT on the dot. once 4 weeks ago, once 5 and 6 weeks ago.
The timing belt is correct.

And also talked to many mechanics, one is the one who do all the machine work for my rebuilt. he works for 30+ years rebuilding engine, and he is very good too. do alot of local racing engine work, very nice, taught me many things, and let me use his machine shop and so on. nice guy. He said lower compression ratio will not lower vaccum. it should stays at 18-22. and he told me many info, and he is having some doubts on either vacuum leak, or ignition timing too advance.

I am pretty sure my ignition timing is advanced too much. how can I slightly accelerate (I mean slow ok) and my timing goes to like 26 or 32 if harder. or more if even harder. even I said harder, I mean when I stopped at a red light, and turn green.. all SUV, Civic, accord, and all go pass me, and I am slowly accelerating to 40mph, coz my EGT already goes up to like 1400F. and it will keep going to like 1500+ if I keep accelerating. do'nt tell me that's normal.
And please don't tell me, cannot go above ~70mph is normal either. I mean, if I wait till my car cool at 1300F or so, and boost 12PSI till my EGT goes to like 1520F, it will slow down then. and I can get to like 90+mph. but if I am normal driving, and want to accelerate, it's impossible. only if I want to melt my pistons.

My fuel is fine. I am getting my WBO2 working soon. but I got my fuel very close. definitely not too lean or too rich at least.
So someone, can I get some info on to if I can adjust my ignition timing? anything went bad or incorrect that will screw up the ignition timing? or it's just that way? (which I think it's impossible to be)

Thanks again for all the help in advance.
Gil

I think you have it backwards about the timing. Too LITTLE of timing advance will cause high EGT's, not too much. Too much timing that is required for the current boost, fuel octane, and engine compression ratio, the engine will get knock, or detonation. Too little timing advance causes high exhaust temperatures because the ignition event of the stroke is happening too late, with the end of the combustion process happening later, during the opening of the exhaust valve. More heat goes out the exhaust valve, instead of staying into the cylinder. Make sense?

Other causes of high EGT's can also be too lean A/F mixture. If you have around 11.5:1 A/F and your egt's are still high, then its too little timing. If you add timing and it knocks, then you need more fuel octane, lower the boost, or lower engine comrpression ratio(not really feasable of course when its all built already).

Now,too advanced CAM timing on the exhaust side can also cause high EGT's, but this is less likely if you are running stock cams, stock gears, ect all timmed correctly.

Also, EGT's are FINE at 1525 degrees. You will find if you were on a dyno, with proper A/F and proper timing for making power, EGT's will be at least that, or around 1550-1575 degrees. Just dont let it get higher than 1575-1600.

too much timing advance will cause way higher cylinder pressures which will in turn, cause heat build up. i melted a set of forged je pistons cause i had too much timing. just got too hot for em. needed to retard my ignition timing a little bit

Originally posted by raptor2323
too much timing advance will cause way higher cylinder pressures which will in turn, cause heat build up. i melted a set of forged je pistons cause i had too much timing. just got too hot for em. needed to retard my ignition timing a little bit

Im sure 5 years ago this may have been relevant.

Originally posted by raptor2323
too much timing advance will cause way higher cylinder pressures which will in turn, cause heat build up. i melted a set of forged je pistons cause i had too much timing. just got too hot for em. needed to retard my ignition timing a little bit

Yes, thank you for adding the information about your melted JEs in the other 3 threads you have brought from the dead. If I see you in person I am going to smack the back of your head in hopes of resetting the commonsense.exe file.