Small Block Distributor
Thread Starter
Instructor
Joined: May 2012
Posts: 119
Likes: 2
From: Kennebunk, ME
Small Block Distributor
Gents,
I've been working on the tune of my 73 with a 355 crate motor, 625 Road Demon and the original distributor with a Pertronix kit. My cam is developing 16"hg at idle. With the help of Lars' papers, I resolved the fuel boil issue and have a decent base set up of the carb (thanks Lars). In trying to set up the distributor, I set the timing to 36 degrees at 4,500rpm and my base timing comes out at 19 degrees at 800rpm. With the vacuum advance disconnected my light says I'm all in at 1,500rpm. I know this is messed up. When we dropped in the crate motor, we tested that the mechanical advance appeared functional, cleaned up the distributor and added the Pertronix kit but that's it. I'd like to get some help with this distributor. Does anyone know of someone in the Mass / CT area that I can bring the distributor to? Or should I should I ship it out to someone that you can recommend?
I've been working on the tune of my 73 with a 355 crate motor, 625 Road Demon and the original distributor with a Pertronix kit. My cam is developing 16"hg at idle. With the help of Lars' papers, I resolved the fuel boil issue and have a decent base set up of the carb (thanks Lars). In trying to set up the distributor, I set the timing to 36 degrees at 4,500rpm and my base timing comes out at 19 degrees at 800rpm. With the vacuum advance disconnected my light says I'm all in at 1,500rpm. I know this is messed up. When we dropped in the crate motor, we tested that the mechanical advance appeared functional, cleaned up the distributor and added the Pertronix kit but that's it. I'd like to get some help with this distributor. Does anyone know of someone in the Mass / CT area that I can bring the distributor to? Or should I should I ship it out to someone that you can recommend?
Burning Brakes
Joined: Oct 2001
Posts: 1,241
Likes: 4
From: Okinawa Okinawa
Sounds like you need heavier springs on the dizzy.
Buy a pack of different weight springs and change them out until you get all in around 2500-3000. Sounds like you are just about there, you just have too light of springs.
Buy a pack of different weight springs and change them out until you get all in around 2500-3000. Sounds like you are just about there, you just have too light of springs.
Thread Starter
Instructor
Joined: May 2012
Posts: 119
Likes: 2
From: Kennebunk, ME
I bought the Mr. Gasket 927 kit and put in the black springs (the weights don't work) and that's whats in there now. I can't verify if the weights are original but they don't look right.
Pro
Joined: Apr 2013
Posts: 535
Likes: 8
From: London Ontario
After spending good money on a new motor why not spend another $100 for a HEI conversion distributor? There are several of the big brand names that sell small diameter one wire kits with tach drive; most under $200. They are rough tuned out of the box and eliminates the guesswork! Not NCRS friendly, but, there is a reason we stopped using points and weak coils. There are even a few on e-bay for $75, but, the large style cap has some fitment issues.
By the way, nice taste in Vettes!
By the way, nice taste in Vettes!
Melting Slicks
Joined: Oct 2012
Posts: 2,156
Likes: 273
From: Dunedin NZ.
Your springs are too light, I think the black are the lightest set no? Try a silver and a black combo and work up from there.
Burning Brakes
Joined: Oct 2001
Posts: 1,241
Likes: 4
From: Okinawa Okinawa
From Lars paper on how to set timing.
"For points-style systems, use one black spring and one silver
spring – these springs will get your total timing all in by 2500-2800 rpm, providing very good throttle response and power."
Worth a try.
"For points-style systems, use one black spring and one silver
spring – these springs will get your total timing all in by 2500-2800 rpm, providing very good throttle response and power."
Worth a try.
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Racer
Joined: Apr 2011
Posts: 471
Likes: 3
... but every distributor is different from the other, I had to use one stock and one gold spring in order to have all in at 2500 RPM...
Drifting
Joined: Mar 2011
Posts: 1,886
Likes: 9
It can be a trial and error process. I use stock heavy springs with modified weights. Sometimes with the very light springs, the advance starts too early. You need the advance to start a few hundred rpm above idle speed.