manifold vaccum for vaccum advance ?'s

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Another reason i think the rings are fine is cause when i first fire up the engine it never smokes out the exhaust, and while its at an idle it never smokes, it never smokes upon acceleration, the only time it will smoke is when you get on it pretty good and let off the throttle. And it only does that while driving. If you in park and rev it up and let go of the throttle it doesnt smoke then ether. It only happens when your driving it and do it.
In my past expirence with an engine that had bad rings it would smoke when you first fired it up and it would smoke while it was sitting at an idle and it would smoke when accelerating from a stop, it just plain smoked all the time. But this magnum only does it when backing off the throttle after getting on it pretty good nd thats it. So it makes sense the valve seal on the number 5 cylinder is cracked or hardned and is letting the oil by and thats why my number 5 plug is drinched in oil.
 
I think you're doing the right thing for now getting the mechanical side straight. Then you can go back and tune if need be. Your compression test was good so i too think the rings are fine. Might throw a set of plugs in when you do the seals just to know they are fresh and not contaminated from the seals leaking. Well at least #5 cyl.
 
ya, i'm buying brand new plugs, but i think i'm going to stick with the ngk v-powers i like them, and i am going to get new pliug wires as well. I bought book called how to build high performance ignition systems. read it 3 or 4 times now, i feel confident that i could wire up a cd ignition. I'm just trying to decide between the crane cams hi-6 or the mallory hyfire VIA. I'm thinking i would most likely go with the crane cams because i already have the crane cams lx92 coil that matches up with there hi-6 box.
I'm thinking i would like having the cd ignition from crane cams and that it would insure i never have a miss fire because i would be getting alot better spark vs running the mopar ecu ignition. That module i paid 50 bucks for from car quest was causing my miss fire because i wired up the mopar gold box that i had laying around and it idled so much smoother and i couldnt hear the thudding out the exhaust, but then again whatever is causing my number 5 plug to get drinched in oil could have also been causing my miss at an idle.
I just bought this book becaise it was on sale for 15 bucks, and it has alot of good information in there, its made by car tech and its written by todd ryden who has worked with msd and other ignition companies. I'm just thinkin getting a cd ignition would be good preventive maintaince, and help out alot at an idle. Plus i could have a rev limter so that i could never hurt this engine. what cd ignitions are best to use n the mopar crowd?
I would have to say that qith what i have read and seen in this book that mallory probably makes the nicest cd ignition. But cranes looks pretty nice too and since i already have the lx92 coil that would save me some money because then i'd just have topurchase the crane ignition box and thats it. I'm also thinking about buying the crane cams fire wire spark plug wire, they have only 25ohms of resistance per foot according to this igntion book i just purchased.
Of course i'm not going to do any of this untill i get the valve seals replaced. Then after i get that done a new cd igniton is going to move to the top of the to do list.
 
but right after i get the valve seals replaced i'm going to thro in new plugs and new wires. I'll keep you guys posted with whats going on. My mechanic friend will be calling me to let me know when he's free to give me a hand with replacing the valve seals.
After i get them replaced i will probably be easy on it for the first 50 miles or so and then see if it took care of the smoke coming out the exhaust problem when backing off of the throttle. I'm buying viton valve seals as well.
 
yes, i wasnt aware of that untill i went to purchase them, i just victor reinz factory replacement seals. They look of good qaulity and they have a metal ring n them ind of like a pinion seal does. I got intake and exhaust valve seals.
This weekend i'm thinking is when my mechanic friend and i will put them in. but not 100 percent sure, depends if he is free this weekend.
 
ok guys, i ot some interesting news for you. For all of you guys who said the thudding out my exhaust while at an idle was a (miss) you were dead on accurate!!
I remember somone on here saying a (miss) could cause the smokin out the exhaust while backing off the throttle from higher rpm's. So last night i was in my shop tinkering with the engine, ever since i had put my vaccum advance hose on ported vaccum i didnt like it and could not get it to run nearly as good compared to with the vaccum advance on manifold vaccum. So i re-adjusted my vaccum advance canister to add 10 degrees of timing at 18 inches of vaccum. Then i plugged the vaccum advance hose back into manifold vaccum and fired it up and listened and sure enought the thudding out the exhaust was still there. So i pulled the number 5 spark plug, because the number 5 plug was the one that was black and i had guessed that i had a leaking intake valve seal. So just for the heck of it i grabbed another plug that i had laying around thats brand new only been ran thru my engine once. And the extra set of plugs that i have are bosch platinum fusions. Anyway i put one of the bosch platinum fusion plugs in the number 5 cylinder and fired it up and holy cow!!! night and day difference in the idle and in the throttle response and in the way it sounded. I took it out for a drive and the acceleration was way smoother then before!!
So i get back home from my little cruise after putting the bosch plug in the number 5 cylinder and i sat back and listened to the exhaust for 5 minutes and i couldnt hear anymore thudding out the exhaust.
After not hearing the thudding anymore i decided to throw my vaccum gauge on it to see what the vaccum reading would be and i it would be more steady, and sure enough vaccum stayed between 17.5 to 18inch and it hardly moves at all, for the most part the vaccum is very steady and if it does move it might go down to 17.5 to 17.8 inches and thats it. But before with the vaccum gauge on it the needle would drop down below 17 inches of vaccum and then back up to 18 inches then back down and then back up very unsteady vaccum. But now the vaccum is alot more steady like night and day difference. Can a bad spark plug cause unstable vaccum? I'm thinking it can because ever since i replaced the number 5 cylinder plug the vaccum is steady and no more thudding out the exhaust at an idle.
Now the reason i had such a hard time believing i could have had a (miss) is because my distributer is brand new curved and phased at fbo systems i have a brand new standard blue streak cap and rotor my plug wires are brand new borg warner selects and my ignition module is a brand new 4 pin Wells module and all my wiring is brand new. And my ignition module is grounded to the engine block and so is my voltage regulator. And the spark plugs i bought brand new about 9 months ago and they are the NGK zrf511's and they dont even have 1000 miles on them yet. So it was real hard hard for me to believe there was a miss because viryually all of my ignition parts were brand new with hardly any miles on them.... so i started doing some re-searching online about plugs just up and quit working, and i found that it can and does happen quite a bit, not only did i read that, but alot of people have reported having NGk plugs that just up and stopped working, i saw more complaints about ngk plugs that up and stopped working over any other plug.
No my last and most important question, The smoking after i back off the throttle from higher rpm's, i took it out after realizing the ngk plug had took a dump and stopped working and i ripped around and got on it pretty good and backed off the throttle to see if it would still smoke out the exhaust and it did, but there wasnt as much smoke as there was previously with the bad plug in the number 5 cylinder. My question is, is it possible that with the number 5 plug being bad for who knows how long now, is it possible there is alot of un burnt fuel and oil on the number 5 cylinder that will need some time to burn off? Just wondering if maybe over time the excess fuel and oil that got into the number 5 cylinder cause of the bad plug will burn away and the engine will stop smoking after letting the throttle from higher rpm's, is that a possibility? Because somone on here said a MISS will cause smoking out the exhaust while backing off the throttle from higher rpm's.
I purchased new intake valve seals and exhaust valve seals and i have a friend with a good air compressor and the valve spring tool and he said one of these weekends when he isnt busy he will call me and i can take it to his shop at his house and that he would help me change them out. I just dont wanna have to do all that work if its possible the smoking will go away now that i have a good working plug on the number 5 cylinder. And just wondering if its possible that there is un-burnt fueel and oil settled in the number 5 cylinder because of the bad plug and thats why i am seeing the smoke after backing off the throttle at higher rpm's. Remember my compression test checked out good every cylinder had between 145 to 150 psi.
Sorry for such a long story, just wanted to tell the guys who were telling me this is a miss that they were right and ask about the smoking issue and ask if its possible that this smoking issue may go away now that there is a good working plug on the number 5 cylinder.
I have 8 of the bosch platinum fusion plugs and i ordered another NGK from the parts house that will be here thursday. But i'm not sure i wanna run the ngk anymore because this issue caused me a big headache and all it came out to be was a 2 dollar spark PLUG!!! so would i be better off just to run all 8 of the new bosch platinum fusions? or should i give the ngk's a second shot and just run the bosch in the number 5 cylinder untill the new ngk gets hee on thursday?
 
I just went through something similar to this and thought I'd share. I have the 390 HP version of the MP 360 Magnum and it has a bit more cam then the 300, I cannot get the motor to idle clean with anything less than 25-30 degrees initial timing.

Don helped me out also with the same advice. I had all that initial timing and my vacuum advance to ported, and was getting way to much total timing. He said to back it down to 34, and I have 18 mechanical so that left me 16 initial, i need my vacuum advance to manifold for my engine to even idle.

Also, just thought it was a bit interesting, but my #5 plug is always darker then the others also....:-k

Sounds like you're getting it all figured out though.
 
well big tooth, last night after i wrote my findings i went out and fired up the engine and i could hear the thudding out the exhaust again. So i took my vaccum advance off of manifold vaccum and put it back on ported.
I did have it at 14 degrees initial and 32 degrees total with the vaccum advance adding 10 degrees of timing at 18 inches of vaccum, and while at an idle my engine makes 18 inches of vaccum. So with the vccum advance on manifold vaccum i was sitting at 24 degrees initial and it just seems to be too much timing for my engine. The thudding out the exhust was back and it just dont seem to like the vaccum advance at an idle .
So i put it back on ported, turned up my initial timing from 14 to 16 degrees and that mad my total go from 32 to 34. And i left my vaccum advace can adding 10 degrees of timing at 18 inches of vaccum.
I just dont know how to tune a vaccum advance can for ported vaccum. Should i set the vaccum advance to add 10 degrees of timing at 18 inches of vaccum or should i set it to add 12 degrees at 18 inches of vaccum or 15 degrees? I figured leaving it to add 10 degrees of timing at 18 inches of vaccum would be ok for now. I have 16 initial 34 total so 18 in the distributer. while at a staedy cruise how much vaccum do you guys think my engine is producing? anout 18 inches to 20 inches or is it making more then that? Because if it aint going to produce anymore then 18 inches of vaccum while at a steady cruise then i could set it to add 15 degrees of timing at 18 inches of vaccum and that would let my total land around 49 or 50 degrees including the vaccum advance while at a high vaccum steady cruise condition.
 
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