datsun-roadsters
[Top] [All Lists]

Re: [Roadsters] [Fwd: Re: distributors]

To: dhyson@charter.net, datsun-roadsters@autox.team.net
Subject: Re: [Roadsters] [Fwd: Re: distributors]
From: Keith0alan@aol.com
Date: Wed, 30 Jul 2008 10:47:23 EDT
If you look in the manual the roadster has a two stage curve. One slope at  
the beginning then another at higher rpm. This happens because one spring is a  
bit longer and doesn't do anything till the other one is stretched out a  bit.
 
keith
 
 
In a message dated 7/30/2008 6:14:44 A.M. Pacific Daylight Time,  
dhyson@charter.net writes:


To:     
References:     



The  springs may not do much with the distributor at rest (not spinning) 
When  it spins centrifugal force makes the weights in the advance 
mechanism  swing out away from their resting position. The different 
tension of the  two springs controls the speed and amount the weights 
move out until the  dizzy is spinning at the speed that gives maximum 
advance. This process of  controlling the weights differently is what 
gives you the spark advance  "curve" that you hear about . If you still 
have the dizzy out and the  springs off try giving the shaft a sudden 
spin with your fingers in the  direction in normally rotates . You will 
see how the weights fly out and  how the springs would restrict them .
Tuning the advance curve with  different weights and springs used to be a 
real common thing.. It is  usually done on a distributor testing machine 
so you can see and record  what you end up with for an advance curve. If 
you run both light springs  you are going to make the dizzy get to 
maximum advance at a lower RPM.  This should lead to the car feeling 
snappier and the engine being quicker  or more willing to rev . The thing 
you must be extremely careful about is  that all that advance may make 
the engine ping and/or detonate. This  will  , in a relatively short 
period of time , kill the engine. I for  one wouldn't try it but you 
should consult some more regular roadster  tuners as I am primarily an 
L-series  , ex-roadster guy .  The  characteristics of what advance curve 
an engine is happy with vary from  engine type to engine type . Even 
within an engine family things like  compression , carb/s , and cams will 
make the best curve different . This  is why I defer to the people who 
fool with roadster engines all the time  for advice on exactly what 
springs you should run  .

Thanks,
Durf


Patti Dwinell wrote:
> Gary,
>  My distributor has two springs of different sizes...one rather hefty wire  
with
> 4 windings and the other rather thin wire with 8 windings.   They are both 
the
> same length. The hefty one was not putting any  tension on the governor 
weight
>  what-so-ever




**************Get fantasy football with free live scoring. Sign up for 
FanHouse Fantasy Football today.      
(http://www.fanhouse.com/fantasyaffair?ncid=aolspr00050000000020)
________________________________________
Support Team.Net  http://www.team.net/donate.html


Datsun-roadsters mailing list

http://www.team.net/archive

http://autox.team.net/mailman/listinfo/datsun-roadsters

<Prev in Thread] Current Thread [Next in Thread>