Tuning

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Dan the man

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I know very little about doing this properly. When I was a teenager I used a timing light, vacuum gauge, tach-dwell meter, feeler gauge as that's all my dad had. What other tools do I need? A good assortment of carburetor jets? What can be done with the ignition system for performance tuning?
 
Those are all the tools you need. A dial back timing light and a vacuum gauge is all you need for an electronic ignition. I like the MP Chrome box or a FBO box. You really don’t need more than that. A lot of guys like the MSD, but for me they always fail. They do help mileage with multi sparks under 3K rpm.

There’s also Daytona ignition for the best top of the line.

As far as initial and etc….. just start with the stock settings and go from there. I find advancing the initial is helpful and limiting the mechanical advance very good to do. Advance springs offer a quicker advance curve. The vacuum advance can also be curved a bit. This is where the MP distributor comes in handy with its adjustable vacuum canister.

Again, start with the stock settings.

Edelbrock, jet and rod kit. Holley? jet kit, IF your carb needs it. Wait until you do the initial tune up.

Extra tools? Flat blade Screwdriver, perhaps those star key drivers for the Edebrock carbs. T10, T15, etc…. Extra vacuum caps????
 
rumblefish360 said:
Those are all the tools you need. A dial back timing light and a vacuum gauge is all you need for an electronic ignition. I like the MP Chrome box or a FBO box. You really don’t need more than that. A lot of guys like the MSD, but for me they always fail. They do help mileage with multi sparks under 3K rpm.

There’s also Daytona ignition for the best top of the line.

As far as initial and etc….. just start with the stock settings and go from there. I find advancing the initial is helpful and limiting the mechanical advance very good to do. Advance springs offer a quicker advance curve. The vacuum advance can also be curved a bit. This is where the MP distributor comes in handy with its adjustable vacuum canister.

Again, start with the stock settings.

Edelbrock, jet and rod kit. Holley? jet kit, IF your carb needs it. Wait until you do the initial tune up.

Extra tools? Flat blade Screwdriver, perhaps those star key drivers for the Edebrock carbs. T10, T15, etc…. Extra vacuum caps????
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Thanks for all your help. Since I'm going to be running a carburetor, do I need a O2 sensor? I've never heard of a dial back timing light how do they work?
 
You don’t need an 02 sensor. They help but it’s not a mandatory item. If you elect to get an 02 sensor, AEM has good stuff.

A dial back timing light is just that. It has a dial that you twist to adjust the light. So when you want 10-15 or 20 degrees advance on the inital timing and a standard light flashes, where does the timing mark go? The dial back will see it when you twist the dial to 20*’s.
 
rumblefish360 said:
You don’t need an 02 sensor. They help but it’s not a mandatory item. If you elect to get an 02 sensor, AEM has good stuff.

A dial back timing light is just that. It has a dial that you twist to adjust the light. So when you want 10-15 or 20 degrees advance on the inital timing and a standard light flashes, where does the timing mark go? The dial back will see it when you twist the dial to 20*’s.
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That's awesome, I need to get me one of those. I'm thinking that this is going to be a very good learning curve for me and enjoyable at the same time. Hope to be in contact with the owner of the duster real soon. I have a friend going with me to help look the car over as he's had more experience with engines than me and also hopefully to bring the car home. I haven't talked about it to much because I don't want to jinx myself like I did in the past.
 
Good morning, Dan.
I suggest you buy a new timing light. That is if yours is quite old.
Basically if you remember how to set up a timing light the light flashes every time the plug fires that you put it on. Like plug is typically #1.
With a dial back light you can set when that light flashes so you can set it to “0” when running then dial it back to what you want your timing to be so when your timing is “all in” or the most retarded or advanced it comes up on the balancer as “0”. It is for really good timing and fine tuning. It eliminates a timing tape on the balancer for those procedures.
I suggested you buy a new timing light because old lights the capacitors go bad over time. This can give you false readings. If yours is newer you’re fine. A basic tune up only needs a basic light.

Timing is really simple, so don’t get over welmed. There are a lot of things you can include, but donot need to. Ask on here for a member that may be close to you and see if some one will volunteer to show you in person to refresh your memeory.
Lots of videos on u tube about this subject.
Again it can be easy or complicated. Go slow and understand each step and you will be fine.
 
Do yourself a favor. Before touching timing, check out what you have now. Like Initial timing, advance curve with vacuum disconnected and plugged. Also, total with vacuum disconnected. Then there is reading while vac is connected. This way you know where you started and can go back if needed. Try finding threads to help you understand what's going on. This is the hardest part of a successful tune.IMO
 
Ignition system and performance tuning.

if your ignition works at all rpms and loads you run the motor at, a different one that costs more won't make any noticeable difference

if you ignition doesn't work at all rpms and loads ...well obviously fixing the issue or a different ignition might

id suggest there would be some gains in a distributor timing....namely recurve/ advance limiting.
to cater for modern fuel. This will allow you to have the same total mechanical advance you engine wants but will allow you to set more initial advance, modern fuel seems to like a bit more than the initial timing specified in the manual

if manuals states 5*BTDC you may find that the car likes 7 or 10 BTDC initial. or more. Mine likes 15.

Any extra added as initial advance needs to be removed from the total mechanical advance.
ideally you get this done at a shop that does distributor work or you dismantle your own, weld or braze up the advance mechanism stop. then use a timing disk or protractor to direct what weld or braze you need to carefully and slowly file off to achieve your aim

and if you are not running the vacuum advance look into hooking it up again


For example standard distributor will add 28 or 29* of advance between 850 rpm and approx 3000 rpm
if your initial is 5* 5* +29* = 34* total at 3000 rpm

if you then set initial to 10 * you only want your distributor advance mechanism to add in 24* otherwise total would be 10+ 29 = 39 total i.e you need to remove 5 * from the total advance you had to get it back to 34*

but its a little more complicated, every 1 degree the advance armature in the distributor adds in is worth 2* when measured at the balancer
so 28* at the balancer is 14 degrees in the distributor advance

so to remove 5 balancer degrees you would need to limit distributor advance by 2.5 degrees


so you weld up the slots a little bit
re build the dizzy
clamp its drive end in a vice
put your timing disk over the rotor shaft
clamp it down
use a piece of wood as a pointer in the cut out in the rotor shaft and point it at 0*
and twist the top of the distributor to swing out the advance weights
if you now have 11.5 degrees as you twist the rotor arm all good
if you don't you need to take it apart again and file off a bit of your weld until you do.

that gets you half way there
i.e the initial advance can be where the motor wants it and you have stopped your distributor adding in so much as to go further than 34 total.

the other half of the equation is tuning how it adds the advance
this is done with the springs.

that's another complication and this is where a man with a distributor machine is helpful

otherwise its a case of weakest springs from a spring set and drive it hard
if it pings change 1 of them for the next strongest
and so on
until it drives without pinging

there are other ways

if you have a specific mopar model of distributor that is supported by the aftermarket you can get limiting disc and spring set which allows you to achieve a range of settings more easily
FBO used to make a kit

once recurved you can start work on the vacuum advance

it can become a bit of a rabbit hole, but the results are eventually a car that is eager off idle
accelerates well
and with the vacuum advance hooked up goes way way further after you lift your foot off the gas.

it will feel like the car just got smaller and easier to drive
and it will run smoother and quieter than it has done previously
fuel economy will be better
the end of exhaust tail pipe will not be black as soot
and anyone on a motorcycle won't be gassed sitting behind you at the stop lights

Dave
 
Remember the adjustable vac advances only adjust the rate of advance not the total amount.

vac1.JPG


vac2.JPG
 
What changes you make to the carb and vac or mech advance, duble check timing... in my experience it isn't always set it and forget it. But I may be doing something wrong...

The set it and forget it car for me is my 5.0 fox body but that has a computer for the "tweaks" whereas the older mopars the tweaks are done by hand.

For example a tune up session may consist of setting the engine up , test driving it seeing if you like it coming back reading plugs double checking timing ,rejet set timing again test drive

read plugs check vacuum, re set /ajust vacuum and mech advance etc. to get even more deeply involved youd use engine tuneup equipment like a scope and a chassis dyno etc. The

latter mentioned tools are now obsolete but thats what a 70s tune up shop had, today it would be the test drive and youll know when its running good youll have a smile on your face

but youll aslo feel the power band the carshould pull all through the rpm range of the cam, you can feel when a car is breaking up in the rpm range or when its falling flat that is what

you are looking for take it out on a 65 mile per hour or faster highway etc.
 
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i'm amazed nobody has said ''tuning what?'' you should get a car first and drive it after the obvious basic checks. it may be just fine as is and you've spent money for nothing.
as has been said many times...... go get a car first :thumbsup:
nei
l.
 
mygasser said:
i'm amazed nobody has said ''tuning what?'' you should get a car first and drive it after the obvious basic checks. it may be just fine as is and you've spent money for nothing.
as has been said many times...... go get a car first :thumbsup:
nei
l.
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There's a lot of "cart before the horse" with this one.
 
Also dont get a smogger LA 318 and expect to tune any more than the given 150 Horse out of it...same with any other mid 70s era smog engine. AND, unless you arepaying top dollar you can expect any Mopar engine in a car to be either A: needing a rebuild. or B: already been gone over who knows how many times...so, in theory you coul acquire a smogger 318 with the wrong cam installed and it be a total dog...but I dont mean to dissuade...:)

I've read that all else being stock in a LA 318 that the factory cam is the best choice, and in all reality and Id bet that's the truth .
 
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Dartswinger70 said:
Also dont get a smogger LA 318 and expect to tune any more than the given 150 Horse out of it...same with any other mid 70s era smog engine. AND, unless you arepaying top dollar you can expect any Mopar engine in a car to be either A: needing a rebuild. or B: already been gone over who knows how many times...so, in theory you coul acquire a smogger 318 with the wrong cam installed and it be a total dog...but I dont mean to dissuade...:)

I've read that all else being stock in a LA 318 that the factory cam is the best choice, and in all reality and Id bet that's the truth .
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I’ve stabbed small cams in smogger engines before. The power increase is disappointing but there. Mostly seen and felt is the rpm band moving upwards. A lot of things hold the engine back from a nice improvement from the cam swap.

Low compression
Small valves
Less than ideal cylinder head chambers and ports

You can only wring out so much with these crippling issues.
 
mygasser said:
i'm amazed nobody has said ''tuning what?'' you should get a car first and drive it after the obvious basic checks. it may be just fine as is and you've spent money for nothing.
as has been said many times...... go get a car first :thumbsup:
nei
l.
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I understand, but what's wrong with doing a little research before hand. I've been away from having to do much on a car for a while now. Everything that I buy and pretty much do I check it out first. And who knows, I just maybe happy with the way it is. I like to be prepared if for some reason the guy ahead of me was a shade tree mechanic or a would be tuner. I understand and agree with getting the car first and not putting the cart in front of the horse.
 
340six said:
So you bought a car?
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Going next week, hopefully this will be the one. I'm really looking forward to it and I have a friend of mine who is going with me to check it out and help me bring it back. 1972 duster with a 360, ps,ac, pdb
 
Dan the man said:
I understand, but what's wrong with doing a little research before hand. I've been away from having to do much on a car for a while now. Everything that I buy and pretty much do I check it out first. And who knows, I just maybe happy with the way it is. I like to be prepared if for some reason the guy ahead of me was a shade tree mechanic or a would be tuner. I understand and agree with getting the car first and not putting the cart in front of the horse.
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Nothing wrong with asking some questions especially if you have an issue you are tying to solve. There are hundreds of threads about the basic questions you are asking about. It's things you need to learn about without us repeating it for the hundredth time. Without a car for us to diagnose, we are literally spinning our wheels trying to answer questions to solve problems that don't exist on a car that hasn't been bought yet. Just sayin'
 
Be one thing if you read a bunch of articles and videos etc.. and had some questions about it that you didn't get.
 
there's nothing wrong with learning or the quest for knowledge and desire to expand your skill set. but... all of this could be answered with a simple search here and reading thru the archives of posts along with, *gasp* u-tube.

i mean, sure if you have specific questions this would be the place to seek granular knowledge of particulars. but that would likely come at the time of performing the actual work, which-- shockingly-- would mean you actually had a car to work on.

get a car first, and then worry about the rest.
 
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