Author Topic: distribution movement curve  (Read 4321 times)

merrill

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distribution movement curve
« on: May 13, 2008, 11:44:46 »
so, I am trying to find the distribution movement curve data for my
009 distributor.

the BBB I have shows the distribution movement curve for
the original distributor for the sl  0 231 116 051  (page 00-0/7)

can I assume the curve for the 051 and the 009 are the same?

does anyone have a bbb that shows the curve for the 009?

Once I confirm the info I plan to send my distro out for test / repair.

thanks

Matt
Austin Tx
66 230 sl - "white"
78 300 D - Blue
98 C230
Matt
Austin Tx
66 230 sl - "white"
78 300 D - Blue
98 C230

Peter van Es

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Re: distribution movement curve
« Reply #1 on: May 13, 2008, 12:59:33 »
I thought all the distributor curves are already in the Technical Manual: http://www.sl113.org/wiki/pmwiki.php?n=Electrical.Distributor
but maybe I'm mistaken.

Peter

1970 280SL. Also known as 'admin@sl113.org' and organiser of the Technical Manual.
1970 280SL. System Admin of the site. Please do not mail or PM me questions on Pagoda's... I'm not likely to know the answer.  Please post on the forum instead!

Naj ✝︎

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Re: distribution movement curve
« Reply #2 on: May 13, 2008, 13:23:24 »
quote:
Originally posted by vanesp

I thought all the distributor curves are already in the Technical Manual: http://www.sl113.org/wiki/pmwiki.php?n=Electrical.Distributor
but maybe I'm mistaken.

Peter

1970 280SL. Also known as 'admin@sl113.org' and organiser of the Technical Manual.



There are no specific curves for the 007 and 009 curves yet, but these distributors are supersessions of the 046 and 051 respectively, so is it safe to assume that the curves would be identical?

naj

68 280SL
68 280SL

merrill

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Re: distribution movement curve
« Reply #3 on: May 13, 2008, 18:21:34 »
Naj, Peter,
the 051 distributor curve data is in the wiki.  

so, here is where I need some education.

It appears the curve data does not match the timing data.

for example, on the curve for 051 the movement on the cam maxes out at about 24 deg (BTDC??) however when one times the car the timing
is supposed to be 30 deg btdc at 3000 rpm.

Am in reading this incorrectly?

Matt
Austin Tx
66 230 sl - "white"
78 300 D - Blue
98 C230
Matt
Austin Tx
66 230 sl - "white"
78 300 D - Blue
98 C230

Naj ✝︎

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Re: distribution movement curve
« Reply #4 on: May 14, 2008, 03:45:39 »
Hello, Matt,

quote:
Originally posted by merrill


for example, on the curve for 051 the movement on the cam maxes out at about 24 deg (BTDC??) however when one times the car the timing
is supposed to be 30 deg btdc at 3000 rpm.

Am in reading this incorrectly?

Matt
Austin Tx
66 230 sl - "white"
78 300 D - Blue
98 C230



Yes, your reading is correct.

The 051 curve shows max advance between 16 and 22 degrees.

The Good Doctor has confirmed this elsewhere on the site where he says that the max centrifugal advance on these distributors is around 20 degrees.

So, when you set the timing at 30 degrees btdc at 3000 rpm without vacuum, you will get idle speed timing at between 8 to 14 degrees btdc.

The vacuum curve shows max retard at between 8 and 14 degrees. So, when you reconnect vacuum, at idle the timing would move back to between tdc and atdc.

This is how it works on my 280SL with an 051. I set the timing at 30 degrees btdc at 3000 rpm and check that it retards when vacuum is reconnected. I dont lose too much sleep over how far back it retards.

We still do not have a good explanation as to why the timing needs to be atdc at all anyway.

I have never seen a 009 dizzy, only a 007 and I beleive the vacuum rod is not adjustable as the 051 is. Could you share some pictures of your 009? We could add them to the wike for future reference.

Above is my understanding of the issue.
Maybe others can chime in and correct me...

naj

68 280SL
« Last Edit: May 14, 2008, 04:55:28 by naj »
68 280SL