: IgnitionMan ...? for you.
Aug 19th, 00, 11:42 AM
as for the ported vs. manifold vacuum.
so ,if i read correctly manifold vacuum for ****y pump gas, and ported if i ran cam2 ?
please just e-mail the response please.i would have mailed you but no address.
Aug 19th, 00, 12:03 PM
Doug, I'm sorry, but I now choose not to respond and will only read from the sidelines.
Please re-read the other post, it does explain the useage of vacuum advance.
Aug 19th, 00, 01:40 PM
Come on Ignitionman, don't let all the BS affect you that way. I don't give a rats' *** if you knew Smokey Yunick or not, his first, his last or his middle name. That's irrelevant as far as I'm concerned. But I've read enough of your responses to know that you're an invaluable asset to this board, and would like for it to continue. To hell with anyone who thinks otherwise. We need to have a little less bashing on this board and alot more Camaro discussions as far as I'm concerned. It's really got me hacked off, but by going away, you're playing right into their hands. Just keep telling it like it is, and if someone chooses not to believe it, that's their decision. I've not always agreed with the way you get your messages across, but the message has always been an intelligent and informative one. That's all that I care about anyway. If someones feelings get hurt in the process, too bad, go sit in the corner and cry about it. And if anyone wants to disagree with me, do me a favor, send me an email, or one to Ignitionman. I'm not writing this to start another war of words..........KZ
Aug 19th, 00, 01:54 PM
Tuning an automotive ignition system is not as easy as everyone might make you think. It is not just a matter of ported vacuum or not ported vacuum. There are so many variables to consider that it is really almost impossible for anyone on this forum, or anywhere else as far as that goes, to dial in your ignition without having your car in front of them to test as they adjust ! Ignition Man probably has more experience than all of us combined in this matter but even his advice is based on his previous experience and may not work on your vehicle ! His is probably the best you are going to get as far as long distance advice and it is too bad everyone else here does not realize that.
The only thing I can advise you to do if you are serious about learning how to tune your car, is to do as much reading as you can on the subject. I dont mean scanning online and getting everyone elses opinion...I mean go buy some books and read up on the subject..how it works, how to adjust it etc. The rest only comes from experience.
I can only recommend one book that I have that I think is pretty good, maybe if Ignition Man Dave has read it he can tell me if I have been snowed by the author. It is called The Doctors book on optimizing the automotive ignition system. It is written my the guy who started Jacobs ignition. Amazon.com has it. I learned quite a bit reading it and I think you will too. It goes through a step by step process of how to optimize the ignition system on your car.
By the way, the same advice goes for Carburetors.
Hope this helps,
Advanced Automotive Machine
Aug 19th, 00, 02:02 PM
I just read your post on vacuum advance ! I normally stay away from the subjects that have a bazillion posts.
I think I learned more from that one post than I have in 30 years of Hot Rodding. I printed it and added it to my Tech library.
Advanced Automotive Machine
Aug 20th, 00, 01:41 AM
sorry you feel that way, i guess all that stuff from "that" post left a bad taste in your mouth.i found it very interesting and informitive...but was a little confused .
Aug 20th, 00, 04:41 AM
BINGO!!! Couldn't have said it better myself!!!! I have EMAILED IgnitionMan stating basically the same thing you have expounded upon here.
[This message has been edited by sr71bb (edited 08-20-2000).]
Aug 20th, 00, 05:15 PM
Ignitionman, I am sorry to see you go! I feel you are doing a disservice to us all here on the board, even those you may have "grievances" with, by not posting any more. As a person who is just getting started in hot rodding I look to persons as yourself to help me along with the more detailed aspects of a sometimes very difficult hobby. The real shame is that you were more than willing to invest your time, which is very precious to all, answering questions which a few could. I wish you did not take your e-mail address off the board so that I could respond to you directly.
Big Block Dave
Aug 21st, 00, 06:00 AM
He'll be back
Aug 22nd, 00, 05:20 PM
Hey Ignition man don't go some of us really need your advice experiance really helps us keep our old cars going without wasting time & money
Aug 30th, 00, 03:15 AM
I missed all the postings from Ignition Mans first reply to the ported vs manifold issue.
I would like to correct him on one of his statements that he made.
"The EGR valve recirculates unburnt gases back into the combustion chamber to be reburned"
I find it very hard to believe that that an engine equipped with 1 7/8 exhaust pipe can redirect unburnt gases through a small 1/2 " port back into the engine to efficantly reduce emmissions by burning unburt gases, The manufactuers added A.I.R. pumps to the engine manifold systems to add fresh oxygen to a super heated exhaust gas to complete the burn process.
By increasing engine temperatures and leaning the fuel mixtures the byproducts of combustion Carbon Monoxide (CO) and Hydrocrbons (HC) were reduced, the draw back to the high combustion temperatures is that an increase of Oxides of Nitrogen (NOx) is produced, Nox gases are the main cause for visable smog, to control the out put of Nox gases the manufactuers added the EGR valve.
If you study the EGR valve, it is temperature controled and does not function untill the engine reaches operating temperature. The EGR valve introduces exhaust gases into the intake system. These exhaust gases are inert and do not burn. in effect all they do is take up space, reducing the amount of fuel / oxygen mixture. By doing this the temperature of combustion is lowered considerably and the
the emissions of Nox gases is reduced.
As for the ported vs manifold issue I would experiment with my car to find which way the car runs and performs best, its not like you have tear the engine apart to change somthing.
Sorry for the long post,
Automotive Technology - A systems approach
Motors publication 1993 Engine tune up and electronics manual
Aug 30th, 00, 07:40 AM
Your publication is full of bull. No unburned fuels in the exhaust? That's exactly why we have emissions reduction systems on some of our engines, to LOWER the amount of UN-BURNED gas that is emitted out the tailpipe into the atmosphere.
E-G-R = EXHAUST GAS RECIRCULATION. Why do we need it, because there is un-burned fuels from incomplete combustion in the first section of the exhaust system the manifods or headers.
EGR is just that. A valve mounted in a place that allows it to connect the exhaust system to the intake manifold internal comptents and passages, takes exhaust gas and recycles it into the combustion chambers to be RE-BURNED.
It's just that simple. Now, to burn what has already been partially burned at a certain temperature over again, the re-burn temp within the combustion chamber has to be hotter than the intial burn that created the first exhaust gas load and its un-burned volume, that is getting burned over again. WE DO THIS BY ADDING TIMING, which increases the burn temp in the combustion chamber and reduces the total level of pollution particulates to the tailpipe.
Since the exhaust gas is pressured past the vacuum depression the fuel is pulled into the engine at, the exhaust gasses will always be available to enter the intake manifold for recirculation. The key is to meter the volume of exhaust gas to intake volume, by regulating the open valve flow of the EGR valve. If you have ever had to replace an EGR valve with a universal one, you would know that they come with a packet inside the package with a number of oriface sizes, one size will be for the engine it will be used on.
Since the exhaust gas is introduced into a vacuum, it is then pulled into the cylinders and re-burned using the added heat from the added vacuum advance degrees of timing.
As far as temperaqture controlled EGR, I have seen that, along with electronic control, from switches, computers and other means, ones that have no switches at all, ones that are standard and ones that are "backfeed", dual-direction and more. Your book only generally refers to the way a standard EGR valve works, doesn't seem to mention specific types of them and their individual useages, operation and contains little to no useable info. Out of date publication at best.
No matter what we all think, the laws of Physics are still in effect. To burn a previously partially burned mixture of fuel and air, within the same confinement it was initially burned in, needs a hotter fire, and timing in our case, does this fire temp rise. Still simple.
Air pumps are not widely used with EGR systems, although there are those systems that use both for a certain type of engine configuration. The EGR system proves to be more effective in lowering particulate emissions than the air pump was.
Best use for an air pump today is for oil pan/lifter valley/rocer cover excessive windage air evacuation.
Once again, I have to defend the truth in a post I have made, and from info in an out-dated and incorrect book. Come on, figure it out, it's right there for all to see. It's getting old, real old. I'm not yelling at anybody or even upset, but this is all just common sense, it is still plain and simple.
Aug 30th, 00, 09:00 AM
Another one to print for reference. My TBI truck has had its EGR valve inoperatable since I bought it 5 years ago. I am sick of having the windows down and smelling exhaust. Don't know if its related or not but I think I am going to get the system to work again. My truck is a 87 that has both the EGR and the air pump system with the air pump parts all missing also since I had it. Runs like a dream but somewhat stinks. Too costly to put the air pump back in circulation but the EGR is on my list of to do's
Aug 30th, 00, 03:54 PM
For sake of debate, I'm going to have to agree with Rob regarding the main purpose of the EGR valve.
Yes, I do agree there are unburnt gasses in the exhaust stream, but using the EGR valve, who's sole purpose is to assist in reburning these gasses, I find hard to believe.
Let's examine the system in it's simplest form. The exhaust system has 8 ports on a V8 engine that average 1-1/2" in diameter. Now to recirculate exhaust gas back into an engine through a 1/2" port to reburn, is like trying to extinguish a burning building with a garden hose.
You are absolutely correct that by adding more timing, the combustion process will increase in temperature and will also more completely burn the gas mixture. But what was stated earlier in Rob's post, was that one of the reactions to this increased temperature was the formulation of NOX gases.
So by keeping the added timing to increase the combustion process and also reducing the NOX emmisions, the mfg's added EGR and catalytic convertors. EGR to reduce combustion temps & the cat's to convert the unburnt gasses.
Here are a couple of sites I found that explain the EGR valves and different types. These are both well known & well respected companies that I doubt would post erroneos or outdated information.
http://www.acdelco.com/parts/tech/1515e.htm http://www.acdelco.com/parts/tech/1515h.htm http://www.smpcorp.com/contt.htm
67 Camaro LS6 454/TH400/12bolt 3.73
1989 TransAm 5.7L WS6 W/all the options
Aug 30th, 00, 07:21 PM
Well, I'm also right about the rest as well. I do this stuff for a living and that's the way it works in the real world.
EGR supply is from the heat transfer, not from 8 individual ports, and in that area, the crossover flow is relatively low and has a fairly low volume as well.
Now, it doesn't take a rocket scientist or brain surgeon to figure one very important fact out about the EGR gas temps, they are HOTTER than the invoming fuel/air mixtures, so they actually don't cool when introduced into the combustion chambers, they heat them up. That's why more chamber temp is needed to burn the excess unburned exhaust particulates that didn't get fully burtned the first time through the circuit.
Intake manifold inside temp: 220/240 d/F
Combustion Chamber temp (average): 600 d/F
Exhaust gas temp (at the EGR valve): 1,000 d/F
Doesn't take a lot to see the EGR raises the combustion chamber temps.
Sorry, but that's the way it works, and nobody can change that, not even me. Live with it.
Believe what you want, who cares anymore. Still means ported vacuum advance will increase detonation sensitivity from being used in the wrong place, no bull. End of my involvement in this.
Aug 31st, 00, 03:29 AM
Sorry Ignitionman I still stand by what I said in my post, Cardude links confirm what I was saying, I did not call your post BS or any thing as such, If you are going to give information just try to be correct, If you feel so strong about what you are saying is so true then please post copies of your publications (or fax them to me) that you are referencing, and I will apologize and eat my words.
Aug 31st, 00, 05:07 AM
Rob, I TAKE THE "CORRECT" STATEMENT TO BE A VERY PERSONAL AFRONT. I NEVER post incorrect information, period. You are in effect, calling me a full-on liar, and that is the one thing I will not stand for. My EGR experience comes from being there and working with it, not just reading about it.
If you look at just what happens in the system, and not blindly read a book, you would find that there are discrepancies in publications, and they get right past some of the smartest people in the world. Others read something and blindly believe it.
I ALWAYS CHOOSE TO LOOK, UP CLOSE AND PERSONAL, NOT JUST BELIEVE A BOOK, and I have not found the books to be right about EGR, just isn't the way the thing works on a running engine.
I don't post lies. I sugest you get your eyes out of the publications and take your own look, you'll find the pubs aren't as accurate as you think. It's called experience over blindness.
If all of us had blindly believed all those books, all of us would still be using old Stromberg 97 two barrel carbs and weak dual point ignitions, instead of marching forward.
End of it, you really don't want to call me a liar again. I don't need anyone "correcting" me when I am not wrong, and I am not wrong on this topic.
[This message has been edited by IgnitionMan (edited 08-31-2000).]
[This message has been edited by IgnitionMan (edited 08-31-2000).]
Big Block Dave
Aug 31st, 00, 05:45 AM
C'mon guys.....this is just becoming an extension of the last post.
Aug 31st, 00, 05:53 AM
Why can't you guys just agree to disagree? Bottom line, try either method on your car, use the one that works best. Real world solution, no books, no sources, no BS. Just 1st hand experience on YOUR car. Case closed.......and hopefully this thread too, we all know where it's going.....KZ
Sep 1st, 00, 09:12 AM
Ignitionman please accept my appoligies, (re the corect statement) My intentions are not to get into a pi###ng match with you, However I am interested in what you are saying in regards to the EGR purpose and operations, The publications are what I have at hand and may well be out of date(1993 & 1996). If in fact that you have information (published) that you can share with me then I would greatly appreciate that you send me copies,
Sep 1st, 00, 01:54 PM
When combustion flame front temperatures exceed 2,500ْ F NOx formation increases dramatically. Exhaust gas resirculation is the most efective way to reduce NOx emissions without adversely affecting fuel economy, driveability, and HC emission control. The resirculation of exhaust gas lowers the combustion temperature by displacing a portion of the burnable mixture. This lowers effective displacement of the cylinder and NOx emissions drop off sharply when EGR is introduced into the air-fuel mixture.
That is directley from "Fuel systems and emission controls class room manual 4th edition" The added ignition timming is not to increase the chamber temperature but is needed to burn the diluted air fuel mixture. When you add exhaust gas to the air-fuel mixture it doesn't want to burn as well so you need more advance to get it to burn completely. The EGR is not there to re-burn any unburnt hydrocarbons. That is the job of the air injection system and the cat. And just beacause a car does not have an airpump doesn't mean it doesn't have air injection. New cars are now using pulse air injection.
Sep 1st, 00, 06:23 PM
?????? just had a thought.if you change your muffler or cat to free flows will it still have enought back pressure to run the egr?????????????
Sep 4th, 00, 04:17 PM
Thank you Snow 427, Just what I was thinking
and for Devils lake Back pressure has no effect on the EGR,
Once the engine reaches operating Temp. ported vacumm is applied to the valve, the valve opens which allows a small amount of exhaust gases into the intake manifold, since there is a vacumm in the manifold, the exhaust gases flow freely into cylinders with the air fuel mixture.
Sep 4th, 00, 06:01 PM
Rob, I respectfully disagree with you, there are positive and negative backpressure egr valves on todays cars and changing some or all of the exhaust could possibly affect the operation of the valve. If I'm not mistaken, GM puts a P or an N at the beginning of the number on the valve.
the bitterness of poor quality remains, long after the sweetness of the low price is forgotten
Sep 5th, 00, 07:10 AM
The EGR valve (Exhaust Gas Recirculation Valve) Recirculates exhaust gases through the intake manifold to be burned again, cooling peak combustion temperature. Dilutes the air and fuel mixture to keep the nitrogen oxide emissions within breathable limits. This comes straight from the ASE tests. The catalytic converter takes care of the hydrocarbons or unburned fuel. (This is not the purpose of the EGR valve) SMOG pump: Sometimes called the A.I.R. (air injection ecirculation pump), it's a belt-driven device designed to force outside air into the exhaust ports. The outside air will supply oxygen to stimulate the continued burning of hot excess fuel and gases leaving through the exhaust valves and passing into the exhaust manifold.
EGR Valve Operation:
Sep 5th, 00, 07:30 AM
What you have stated up above is what I have learned recently at a very reputable tech school and what BMW teaches there technicians. This is also on the CURRENT ASE tests. I have completed 6 of the ASE's so far. Now I'm not saying anyone is wrong or a liar here but this is just what I have learned. There is nothing wrong with debate but we all must respect each others opinions and not get violent. Lets have some fun and relax....
Sep 5th, 00, 05:09 PM
Hey listen guys I am in no way wanting to be disrespectful in any way shape or form by getting into this. I just can't get it through my thick head that the EGR is to recirculate gases to be "reburned". Every thing that I have learned about the EGR is as I stated above.
If any one has some factual documents supporting the reburn theory, I would be most interested in getting a copy, please send them or e-mail to me.
I stand corrected by Chev64 that exhaust back pressure does effect the operation of the EGR.
Sep 5th, 00, 05:46 PM
thats what i thought.