Timing = heating?

The post includes heating ? which if your only setting the initial at 4 degrees that low setting will cause heating. Your initial timing for a well built flathead should be at least 10 degrees initial and possibly as much as 12 degrees. If you the initial is set to low when you try to rev the engine it will have a bog and then it will rev this is caused by late timing. The total advance for a blower motor should be no more than 20 degrees. And as others have pointed out you want the total advance in as soon as possible I like to see it all in around 2000 RPM. Mallory's springs are usually to heavy to allow the advance to come in at a low enough RPM point to allow the flathead to run correctly
You may ask how do I know all this its from what I learned driving the many highly modified flatheads I own and have built for others over the last 40 years. Example the blown flathead in my Land Speed Race car has a total of 20 degrees so far on gasoline in the mile the speed is over 174 MPH.
 
The initial timing isn't as critical as timing above idle. The important numbers is through the rev range at driving speeds and total.
Sure a real stout cam will want more initial, but for 3/4 ish cams 6-8 should be plenty, if it idles good and the right springs are in there allowing advance to work right off idle and it don't bog, your fine. We don't drive these at idle, and to much initial timing can kick back on the starter, with original starter your gonna be braking the starter spring.
Martin.
These flatheads Will run "ok" with timing a fair way out, but they run great with it set right.
 
I am assuming this is a later model Mallory ignition.
MALLORY URBAN MYTHS:

Most of the late model ( stamped elvis gold insides) come with what i best call a chevrolet curve!! You can bet the tech on the tech line has never touched a flathead .....

This is usually 28 degrees (or more) at 2500 rpm. too much

The plastic keys they give you are a reference and nothing more , we have them but usually adjust on a machine and dont use the keys.

Advance rate is adjusted by bending the spring tabs inward or outward and very seldom do we see the need to change a spring. (this can be done thru a hole in the upper plate on the engine if you are patient...)

I usually set up a blown flathead at 14 degrees maximum with the intial timing set at 0 degrees . Then if more bottom end is needed you can adjust the static to 4-6 degrees etc...

A blower creates and adds heat to the engine and this heat has got to be managed as well....
 
Fourdy said:
Wow, you guys are fast.

I do have the btm and is set to 1.5 per J. Abbin. Joe is fantastic to deal and work with btw.

My pulley has been marked with tdc and tic marks for timing.

I have tried a dial-back light before and it was all over the place. I was told that they don’t work well with MSD electronic ign. I have a regular light and will try that.

When you say check for timing coming in too late are you just saying to check for max by 3000 rpm? Yes, I am learning about pink, brown, gray, purple springs. LOL

I will start at 4 after at idle and go for 24 total or on the 20 mark on the pulley.

I will put together a post about the heads off soon.

And, thank you so much for your advice and patience with us slow learners.

Fourdy
Click to expand...

While you are on a roll take the distributor our and disasemble the advance unit and remove center from upper shart ( held in with a clip). Remove the factory Mallory silver concrete mix that they use for assemble ( and shelf life) . Clean and relube all parts using a light spray lube and reassemble. You can feel the difference with your hand. Now adjust the small spring ( low speed)tension by bending to obtain a light tension and feel the return ( a snap back) again in your hand. Then adjust the heavy spring to just have light contact with no actual tension when in the returned position.
Might need to lower the advance max adjustment to approx 14 degrees .

You should be able to hold the distributor gear in your hand and feel the advance when turning the rotor and it should always return to the 0 setting when released. Once correct you can feel it !!!!!!!!!!!
 
Bubba, 14 degrees maximum? He's got a boost retard module, this will retard timing approx 1-1.5 degrees per pound of boost. He should be able to run 24 ish maximum with that retard module.
Also, initial timing, 0 as in zero, zilch nadder? I need to know your thinking here, surely that'll boil itself just idling? Don't sound right to me.
With your spring tab bending, what rpm all in are we looking at here? I normally fit the lightest springs from the kit for a light car with a slightly built flathead. Works good, sometimes I wish there were lighter springs in the kit, would save me fecking about looking for suitable lighter springs then modifying them to fit.
Genuinely looking for your thoughts here, my results seem to differ wildly from yours.
Many thanks,
Martin.
 
scooder said:
Bubba, 14 degrees maximum? He's got a boost retard module, this will retard timing approx 1-1.5 degrees per pound of boost. He should be able to run 24 ish maximum with that retard module.
Also, initial timing, 0 as in zero, zilch nadder? I need to know your thinking here, surely that'll boil itself just idling? Don't sound right to me.
With your spring tab bending, what rpm all in are we looking at here? I normally fit the lightest springs from the kit for a light car with a slightly built flathead. Works good, sometimes I wish there were lighter springs in the kit, would save me fecking about looking for suitable lighter springs then modifying them to fit.
Genuinely looking for your thoughts here, my results seem to differ wildly from yours.
Many thanks,
Martin.
Click to expand...

First of all these units are not the best ever made by no means. My first concern is to get the distributor adjusted with a maximum advance stop, so that no matter what happens the advance is no more than 14-16 degrees .
This allows setting the intial as needed based on engine cam shaft , blower set up etc....

The flathead likes the advance curve in fairly early at 2500 rpm or so.. and very seldom do you need a spring change , the bendable tabs are pretty nice. (If so we use the spring kit for a chevrolet from summitt
http://www.summitracing.com/parts/mrg-928g/overview/make/chevrolet)

I have found theres more work needing to be done to the blown air fuel ratios than the ignition. Especially if your haveing a over heating issue....
:)
 
scooder said:
The initial timing isn't as critical as timing above idle. The important numbers is through the rev range at driving speeds and total.
Sure a real stout cam will want more initial, but for 3/4 ish cams 6-8 should be plenty, if it idles good and the right springs are in there allowing advance to work right off idle and it don't bog, your fine. We don't drive these at idle, and to much initial timing can kick back on the starter, with original starter your gonna be braking the starter spring.
Martin.
These flatheads Will run "ok" with timing a fair way out, but they run great with it set right.
Click to expand...

The inital timing isnt critical ? Wow I learn something new every day! :eek:
 
Ronnieroadster said:
The inital timing isnt critical ? Wow I learn something new every day! :eek:
Click to expand...
I caught that statement as well, but i think what he meant was that the total static timing is the most important number.
The chevy guys running sprinters etc dont ever have a clue where the intial spark timing is but they do know where the maximum advance is for sure. Many just run fixed advance and set the timing with a light at 3000 and above rpm.......never bothering to look at intial.

The mechanical advance curve patches all the other issues in your program that are screwed up..........ie......air fuel ratios, power valves, accel pumps , carb cfms and so on....
 
Bubba,
I have a wideband a/f meter to install also. Thanks to all of you I have sure learned a lot these last few days. Love it!!

Fourdy
 
Bubba, thanks for your answer explaining your view. I like the all in advance to be earlier than 2500 rpm, hence me changing springs rather than blending the tabs.
Ronnieroadster, I said "as critical" as timing above idle, ie total or maximum advance. I never said it isn't critical. Please don't misquote, it confuses the issue. And I stand by my statement, maximum advance and rate of advance are more important than initial advance.
Fourdy, hope you have a better grasp on what goes on with the ignition.
Martin.
 
Advanced timing doesn't make am engine run cooler. Retarded or late timing makes it run hotter.
So if the timing wasn't advanced enough, ie it was retarded, then advancing the timing would make it run cooler. But you've only advanced it to the correct point.
Make sence?
Your on the right track, with the more efficient burning though.
Martin.
 
Scooder you wrote The initial timing isn't as critical as timing above idle.

This post title Timing= Heating If you start with the initial to low it will cause heating especially in a modified flathead the initial is CRITICAL . Any other way of spinning it is incorrect. My experiance is not be the seat of a computer chair its by the drivers seat of the many flathead powered vehicles I have tuned powered by stock and modifed flatheads.
 
Just reporting what I've found in my experience of working with lots of different engines and vehicles. Be they flathead Ford's, overhead valve, overhead cam, twin cam, 4,6,8,12 cylinder
Not going to argue about it, please remember, I never said it's not critical, and I never questioned your experience.
I totally agree, that if the timing is to low, it'll get hotter quicker. I personally think every ignition should be checked for timing, wether that be on a machine or bolted to the engine. Idle-maximum advance. To confirm what the curve really is. I really like to try and get the best I can with the curve. This leads to modifying the curve quite a bit, but I enjoy doing it.
Cheers,

Martin.
 
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