Punisher66j
Dart Swinger
First off he isn't my tuner. He is a friend of mine helping me out and we are tuning it together. I have been told by multiple people that a 750 holley is plenty good. Wrong for my intake how? Elaborate for me please.
Use or don't use vacuum advance on distributor???????????????????
- Thread starter duster360
- Start date
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Do you realize how much of this back and forth could have been avoided if you had been up front with your problem and answer the questions that were asked of you? There are some incredibly smart people (not me, I'm not that smart) here that are trying to help. Try listening. If you have a stock 5.9 Magnum with only a dual plane intake (Performer?), that is not the right carb.
Can you run that carb on the street? Yes you can. Will it be the best carb you can run on the street? Well, how's it working out for you so far?
I'm out.
yellow rose
Overnight Sensation
Why is it the wrong carb? You're the one saying it. What's wrong with it? Too big? It isn't too big. So what's the problem?
Punisher66j
Dart Swinger
IF you are not going to help go sit on your thumb I am tired of dealing with you.
Punisher66j
Dart Swinger
Thank you. I don't remember being rude or anything I asked a simple question because I am trying to learn and this guy is being a d bag. My first question was how to tune the motor to work with manifold vacuum because hooked up the car sounds like crap compared to not hooked up. I do realize I am working on the carb as well but I feel I am battling two problems.
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Douche Bag? Really? Go buy your lean burn distributor, I'm sure your car will run perfect.
Punisher66j
Dart Swinger
All the lean burn one is is a mechanical distributer. I and others have asked you questions and to elaborate and you won't and then get a attitude basically calling me stupid for trying to learn. If that isn't be a d bag and a know it all I don't know what is.
Look dude, you were asked very specific questions about your engine/car/combo/intended purpose. You pretty much skipped answering any of them just getting it was STOCK 5.9 Magnum and some wazoo double pumper carb was painful and like pulling teeth. How long did it take you to say you had a problem with it hesitating (I believe your term was sputter)? It took how many posts to get you to say it hesitated and then charged on?
Tell me where I said a 750 was too big? I've run much bigger carbs on the street. I'm saying that is the wrong carb for a multi-purpose street car, and yes, there are exceptions, but you haven't given any indications that you are the exception. That carb was built for a specific purpose. Are you using it for that purpose or are you trying to get it to make do? Several people have asked you questions to HELP you, but you blew them off and told them it didn't matter. If it didn't matter, why did they ask? Remember you're the one who said you're learning, yet somehow you know what is more relevant than the people trying to help you learn and get your car to where you can enjoy it. How many weeks have you been having this problem?
There is only one person here making you feel stupid and it isn't me.
fishy68
Tyr Fryr's Inc.
It's a little big but the big issue is he said it is a stock engine with a 750 double pumper. That is wrong IMO. I have tuned carbs for over 35 yrs. and can make a double pumper run ok on a stock 360 but find a vacuum sec carb is much better matched to a stock engine.
DesertRat
Leading edge boomer
I'm doubting I can be of any help either but your are right about battling two issues at the same time.
IMO your main problem is fuel, motors don't die after 2000 RPM on ignition issues. Float bowl fuel level, jetting port synch, something is the fuel system.
The ignition could be an issue but it is definitely secondary.
I'm out now too. Best of luck to you, it should run like a squawking monkey when you get it.
IMO your main problem is fuel, motors don't die after 2000 RPM on ignition issues. Float bowl fuel level, jetting port synch, something is the fuel system.
The ignition could be an issue but it is definitely secondary.
I'm out now too. Best of luck to you, it should run like a squawking monkey when you get it.
Punisher66j
Dart Swinger
Only reason I said it didn't matter initially was because I was trying to keep it about the distributer and how to get the distributer to work with manifold vacuum. I was trying to keep it on point. No matter my set up and whether I am running a slant six with a one barrel or a 440 with dual quads I was trying to ask how to tune a motor any motor to manifold vacuum. I know I have issues with the carb but I didn't want to high jack a distributer thread with carb questions.
OK, you tune the engine to work with the vacuum advance connected. You don't "get" the distributor to work with manifold vacuum, it already will.
Punisher66j
Dart Swinger
Right but how? What needs to be done? Let me start it over because we are frustrating each other and that is not my intention so for that I apologize. I do want both problems fixed. If I can use the vacuum advance I want to but the only option is with manifold vacuum I do not have ported vacuum. Only reason I wanted to adjust the vacuum can is to make it take more vacuum to advance the distributor. Right now it advances at idle. I am idling at 850. If I hook it up the things sounds like a tractor.
MOPAROFFICIAL
Oogliboogli
Vac advance= gas mileage.
If it cleans up anything below cruise by means of direct manifold vacuum...its because the tune sucks.
With guys running real high dynamics...that vac just does not drop off quick enough...the cylinder pressure catches the timing between vac adv and full mechanical and you get a nice lil clack/ping whe you dip the pedal hard.
It's all about what you're building imo, if its hp...plug the hose and walk away.
If it cleans up anything below cruise by means of direct manifold vacuum...its because the tune sucks.
With guys running real high dynamics...that vac just does not drop off quick enough...the cylinder pressure catches the timing between vac adv and full mechanical and you get a nice lil clack/ping whe you dip the pedal hard.
It's all about what you're building imo, if its hp...plug the hose and walk away.
yellow rose
Overnight Sensation
If you can't make a double pumper work on the street you need to take up golf. A vacuum secondary carb is a boat anchor. Always has been, always will be.
So, the carb tune may be off a bit, but it isn't too big.
I'm so sick of the VS street carb lie I could spit tunnel Rams. What a bunch of horse crap.
So, the carb tune may be off a bit, but it isn't too big.
I'm so sick of the VS street carb lie I could spit tunnel Rams. What a bunch of horse crap.
yellow rose
Overnight Sensation
IMO, and I was going to stay out of this part of it, but junk the vacuum advance, get the right curve in the distributor and forget about it. You need to be at 35-36 total. Get it all in by no later than 2500, 2000 would be better.
The vacuum advance was for cars with DEAD STOCK parts. With the right tune up, the VA is a waste of time.
Your car should run good without the vacuum advance hooked up. I can go to any great running motor, unhook the VA and it will still run great. I think your battling more than one problem.
Forget the VA for now. Get the initial timing set, and the total timing set. Then, I'd look into fuel delivery. Maybe a buddy will loan you a carb that has been proven to be a good carb, and start there.
P.S. - a 750 dp carb will run just fine on your stock 360 magnum. Maybe not that particular carb, but in general, a 750 dp holley will work just fine.
Forget the VA for now. Get the initial timing set, and the total timing set. Then, I'd look into fuel delivery. Maybe a buddy will loan you a carb that has been proven to be a good carb, and start there.
P.S. - a 750 dp carb will run just fine on your stock 360 magnum. Maybe not that particular carb, but in general, a 750 dp holley will work just fine.
MOPAROFFICIAL
Oogliboogli
Hey man, does the thing cut out and then go....? That's called pump shot tuning and ppints to not enough or lean...so what number is on the shooter? FWIW an automatic trans car will usually like a #31 or sometimes bigger if there is a high stall convertor envolved...and the pump cam usually an orange/red/pink color, try the screw, 2nd hole.
If its bogging...whhhhhhaaaaaaaaaaa....then goes...its too much pump shot, smaller shooter or and smaller pump cam profile, white one if I remember right or try no1 hole on red and a 28 shooter....
It it bogs the entire rpm range...then its too rich, jets.
The carburetor isn't too big, though it isn't flowing under 4500 at the velocity a 600 cfm would in which that 600 cfm would enhance the low end snappiness/torque...it would be lacking above 4500 rpm in where the 750 cfm will Piss on the 600.
Tuning, "timing" "lean jetting" can make the diff in lower rpm range next to nothing, same diff between the two tuned the same of course...but the 750 will come out ahead on any high speed acceleration .... Don't know the cam, didn't read the entire soap opra, but there it is in short hand lamens.
As for lean burn distributors...no advance plate if I remember and maybe it was dual pickups one intial and one high speed...but can't remember being that I avoided all that GARBAGE when parts shopping the yards back then.
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mderoy340
Well-Known Member
You need a baseline to work from. Get ignition set first then work fuel.
Running manifold vacuum adds timing at idle. If you want 20* timing at idle you add initial mechanical and vacuum advance together. Let's say your vacuum advance can has 15* advance, you set initial to 5*. Set timing to TDC and then hook the vacuum hose up to see how much vacuum advance is in the can you have. Adjust initial accordingly to get it where you want.
Vacuum advance is built into the can and is usually marked by a number on the lever. An 11 can means 22* at the crank. The 3/32 allen adjustment changes the vacuum required to start vacuum can to move. Counter clockwise decreases advance, clockwise increases advance.
My magnum ran best ET at 34* total mechanical.
Stock cam I would start at 20* intial and 34* total 45-50* hiway cruise.
Read this thread for more info:
Vacuum advance tuning to maximize cruise MPG?
Running manifold vacuum adds timing at idle. If you want 20* timing at idle you add initial mechanical and vacuum advance together. Let's say your vacuum advance can has 15* advance, you set initial to 5*. Set timing to TDC and then hook the vacuum hose up to see how much vacuum advance is in the can you have. Adjust initial accordingly to get it where you want.
Vacuum advance is built into the can and is usually marked by a number on the lever. An 11 can means 22* at the crank. The 3/32 allen adjustment changes the vacuum required to start vacuum can to move. Counter clockwise decreases advance, clockwise increases advance.
My magnum ran best ET at 34* total mechanical.
Stock cam I would start at 20* intial and 34* total 45-50* hiway cruise.
Read this thread for more info:
Vacuum advance tuning to maximize cruise MPG?
Punisher66j
Dart Swinger
I went home last night and changed my initial timing to 16 and my final to 360 all in by 2500. I then checked my plugs and they were white so upped the jets. Front I changed to 64s from 62s and back to 66 from 62 and it made a huge difference. I will drive it a little today and then pull another plug and see what happens. I think I am going to just leave the vacuum advance unplugged and not mess with the distributer.
fishy68
Tyr Fryr's Inc.
I'm out. I've posted problems I've ran into several times concerning this issue and the person asking the questions doesn't even respond. Then the horse crap about vac sec carbs being boat anchors and vac advance is for pure stock engines, well it's just that, horse crap. Now I see why I've seen so many people flame this individual. Wasted time on here anymore. Just wasted time
yellow rose
Overnight Sensation
Punisher66j
Dart Swinger
First off I said nothing about vacuum advance being for stock only, or vacuum secondaries being junk. Oh well I have it up and running fine. Thanks to those who did help.I'm out. I've posted problems I've ran into several times concerning this issue and the person asking the questions doesn't even respond. Then the horse crap about vac sec carbs being boat anchors and vac advance is for pure stock engines, well it's just that, horse crap. Now I see why I've seen so many people flame this individual. Wasted time on here anymore. Just wasted time
yellow rose
Overnight Sensation
He was throwing a dig at me. Not that I care. I'll say it again...any Holley vacuum secondary carb is a boat anchor unless the rules make you use them. So go easy on him. He is still stuck in 1980.
Not sure if I missed anything on the exhaust side of this thread on the carburetor, but does it have decent size dual exhaust system that's unrestricted?
Glad the timing is better.
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