carb timing.... Options

[bd1308]

is it 27 or 35 or some number in the middle?

i've seen 35 before.....

FI mark is 27 or 28degrees.....


which is it...help please.


b

[Dave_Darling]

Yes, somewhere in there is good.

No, really... Pick a number and stick with it. If you're using the stock distributor, the stock number is a good choice. If you're using an aftermarket one, then you'll have to mess with it until you get a result you're happy with.

--DD

[bd1308]

*cough*

according to the PP tech article, carb timing is on 35degrees.....


seems a bit too far....oh and from what i understand, the vacuum connection on the carb is useless, so i am just leaving vaccuum retard disconnected.

could I *go* up there (to the fat fan blade, which is i think 35 degrees) without ping...?


b

[Aaron Cox]

what dizzy?

i run my carb'd car at 29.
it varies....by dizzy

[bd1308]

i am running the stock 2.0 FI dizzy.....

i know that 050s and 009s suck

[Aaron Cox]

QUOTE (bd1308 @ Oct 13 2005, 06:41 PM)

i am running the stock 2.0 FI dizzy..... i know that 050s and 009s suck

(IMG:http://www.914world.com/bbs2/html/emoticons/rolleyes.gif)

how do you know they suck? have you tried them? (IMG:http://www.914world.com/bbs2/html/emoticons/dry.gif)
single carbs suck....

[bd1308]

have you seen the inside of a 009?


i've heard they dont have a sufficient advance curve for what i need....


single carbs work well so far....anything bigger and i'll go with dual IDFs....

AAron, we're straying from the topic.....27 or 35.....

[Gint]

My carb'd 1911 ran great with an 050. I'd spare the stock 2.0 and save it if you have an 050 to use.

And there are too many factors that will affect how much advance you're going to use on a carb'd motor. Start at 27 and see how much advance you can use before it causes "issues".

Try it. See what works. You'll probably learn something while you're at it.

[bd1308]

well okay....


i would run 27 without question...but if i push it farther, how do i know if i'm pinging if i cant hear it?


loss of power?

this thing ran like a raped ape (compared to my tired 2.0) when at 35 degrees. when i used the timing light, i saw the wide fan blade thing marking the 35 degree mark....

[SGB]

Mycar has had dual carbs (I know.its not a SINGLE, but I'm getting by) since I got it 15 years ago with the stock 2.0 diz.
I had 009(s) for years, then 050. These were before mexican manufacturing- well made but I just wore'emout. Now I have a Mallory.
ALL OF EM, Ihave static timed to 10 or 11 degrees BTDC.
And that is pretty much what jake recommends, 'cept using the springs in the Mallory to get to max advance quicker and stop advance beyond 28 BTDC. That setup is really for dual webers- When mine is set that way it seems to have more power at high RPMs than when advance was goingall the way to36 or whatever the other units allowed. Mine hops up to 28 by 3200 rpm and it goes great!

[bd1308]

see...how do i set static timing?

I was always confused by that....

set using a protractor?

[Aaron Cox]

QUOTE (bd1308 @ Oct 13 2005, 08:32 PM)

see...how do i set static timing? I was always confused by that.... set using a protractor?

Bear with me as we go through our HYPOTHETICAL settings...

Your dizzy has X degrees of throw (advance)

lets say it has 16 degrees of total advance.
and you want your total advance to be 28 degrees.

then you static time it to to 28-16 = 12 initial degrees of advance.

get yourself an adjustable advance timing light.
at idle for ex, you turn the knob to 12, and you turn the dizzy until you see the TDC mark. (the light DELAYS the flash X degrees... {whatever the knob is turned to})

and at 3k or whatever you are timing max advance at.. turn it to our hypothetical 28. it should read TDC.

[bd1308]

aaron, i didnt grow from a tree man....

I know about adjustable timing lights....i do not own one. nor can i purchase one right now.

if i time to 27 total advance, okay....I can do that.

if i time to 35 total advance, okay....I can do that too.

I can compile programs and configure cyrus and imap.

I simply asked where, not how to time. Initial timing, or static timing is done with the engine at TDC on cylinder one. The advance is then adjusted until the difference between the rotor tip and the TDC point(assuming to be the notch on the dizzy) reads 10-12 degrees.....

I'll just do 27 degrees....


b

[ArtechnikA]

QUOTE (bd1308 @ Oct 14 2005, 03:00 AM)

...static timing is done with the engine at TDC on cylinder one.

uh.... no....

static timing means to set the timing when the engine is not running. (that part you got right).
it is not done at TDC unless you want it static timed at 0 degrees advance... (you may wind up there, if your distributor doesn't have much total advance... but you don't want to start there.)

the spark happens when the points open. so you set the engine to where you want the spark to occur (5* BTDC is a good starting point - and that's 5* crankshaft, just like all timing specs... (with the possible exception of distributor advance curves, which is a topic for another day...))

then you rotate the distributor until the points *just* open at that point. if you have ignition, you can do this with a 12V test light connected between Terminal 1 and ground. when the points open, the light will light. (you can do this with the engine out of the car, using an ohmmeter or continuity tester.)

there is no magic. you want 6* initial (static) advance? you turn the engine so it's at 6* BDTC and rotate the dizzy to achieve that.

or you can time for total advance with the engine running and let static fall where it may. the problem with that method is you have to know how much dynamic advance is in the distributor. if you don't, one number is as good as the next.

[bd1308]

okay...

i'll just time to the FI mark then....



worked fine before, it'll work fine now.


b

[Dave_Darling]

The Pelican article, as I recall, talked about either 30 degrees or 32--not 35. It was also using an aftermarket distributor. Since you're using the stock distributor, set the timing the stock way-- 27 deg BTDC at 3500 RPM with the vacuum hoses (if any) disconnected and plugged.

--DD

[bd1308]

thanks DD


b (IMG:http://www.914world.com/bbs2/html/emoticons/biggrin.gif)