Distributor questions..........
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Distributor questions..........
Ok, first, in the old days when you could get good gas we used to put in light springs to get all the mechanical advance in fast. What about today with 91 octane tops or yuk green gas? The kits come with 3 sets of springs??? (base motor 250hp, stock)
Next, the little bushing that goes under the weights that limit the advance has disintegrated and my timing is all over the map. Can you put that bushing in without taking it out and apart? Thanks guys.
Next, the little bushing that goes under the weights that limit the advance has disintegrated and my timing is all over the map. Can you put that bushing in without taking it out and apart? Thanks guys.
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Yeah - your avatar is too distracting. You need to pull the distributor to put in the bushing. I have Plymouth, Chevy and Ford cars and get some of the various distributor dissassembly steps all mixed up without having it in front of me - but even if the the GM is the one with the hairclip inside the shaft that allow removal of the cam to access where the bushing installs on the pin - you don't want to be messing with that while it's still mounted in the car.
I've kind of evolved on the subject of distributor springs myself. I used to follow the common approach from the 60s which was the lightest springs the better. I don't like to have any of the centrifugal advance wandering in and out in the idle speed range - and with a real light spring wandering is an apt discription. So, I've either gone to the middle springs - or one middle spring and one light spring as long as it doesn't start to advance until off-idle. That may keep it from all coming in until 3000 +/- rpm but with today's gas it seems to me that that is probably appropriate.
That's the peanut gallery input - maybe LARS will weigh in or you can PM him.
I've kind of evolved on the subject of distributor springs myself. I used to follow the common approach from the 60s which was the lightest springs the better. I don't like to have any of the centrifugal advance wandering in and out in the idle speed range - and with a real light spring wandering is an apt discription. So, I've either gone to the middle springs - or one middle spring and one light spring as long as it doesn't start to advance until off-idle. That may keep it from all coming in until 3000 +/- rpm but with today's gas it seems to me that that is probably appropriate.
That's the peanut gallery input - maybe LARS will weigh in or you can PM him.
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Yeah - your avatar is too distracting. You need to pull the distributor to put in the bushing. I have Plymouth, Chevy and Ford cars and get some of the various distributor dissassembly steps all mixed up without having it in front of me - but even if the the GM is the one with the hairclip inside the shaft that allow removal of the cam to access where the bushing installs on the pin - you don't want to be messing with that while it's still mounted in the car.
I've kind of evolved on the subject of distributor springs myself. I used to follow the common approach from the 60s which was the lightest springs the better. I don't like to have any of the centrifugal advance wandering in and out in the idle speed range - and with a real light spring wandering is an apt discription. So, I've either gone to the middle springs - or one middle spring and one light spring as long as it doesn't start to advance until off-idle. That may keep it from all coming in until 3000 +/- rpm but with today's gas it seems to me that that is probably appropriate.
That's the peanut gallery input - maybe LARS will weigh in or you can PM him.
I've kind of evolved on the subject of distributor springs myself. I used to follow the common approach from the 60s which was the lightest springs the better. I don't like to have any of the centrifugal advance wandering in and out in the idle speed range - and with a real light spring wandering is an apt discription. So, I've either gone to the middle springs - or one middle spring and one light spring as long as it doesn't start to advance until off-idle. That may keep it from all coming in until 3000 +/- rpm but with today's gas it seems to me that that is probably appropriate.
That's the peanut gallery input - maybe LARS will weigh in or you can PM him.
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The bushing can be put in while the distributor is in the engine. You will need to take off the rotor, springs and weights. Locate the pin under the advance plate and you can use a pair of channel locks to squeeze it onto the shaft. You can check it with a mirror.
Use the black, stiffest, springs to start and see where the curve winds up.
Joe
Use the black, stiffest, springs to start and see where the curve winds up.
Joe
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I was going to point out that today's pump gas is pretty much the same octane rating as 'the good old days' after the difference in (old) RON to (new) AKI ratings is taken into account.
Such talk seems to upset some people though.
Such talk seems to upset some people though.
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From: Central Arkansas
That is probably pretty much true for run of the mill premium fuel back then and premium fuel now. But, back then we had easier access to a few lines of super-premium at the pump with 100 to 102 octane on the old system (and it was relatively cheap). Dial up the timing, fill her up with super-premium and go have some fun.
At least in my part of the woods I don't see any ready access to anything like Sunoco 260 unless I got to a speed shop and purchase a small barrel of it to pump in by hand.
At least in my part of the woods I don't see any ready access to anything like Sunoco 260 unless I got to a speed shop and purchase a small barrel of it to pump in by hand.
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But Mike- Why does that crap they sell today smell like a combination of drip and kerosene?
That is probably pretty much true for run of the mill premium fuel back then and premium fuel now. But, back then we had easier access to a few lines of super-premium at the pump with 100 to 102 octane on the old system (and it was relatively cheap). Dial up the timing, fill her up with super-premium and go have some fun.
At least in my part of the woods I don't see any ready access to anything like Sunoco 260 unless I got to a speed shop and purchase a small barrel of it to pump in by hand.
At least in my part of the woods I don't see any ready access to anything like Sunoco 260 unless I got to a speed shop and purchase a small barrel of it to pump in by hand.
Premium gasoline fumes is not an unpleasant smell.
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That is probably pretty much true for run of the mill premium fuel back then and premium fuel now. But, back then we had easier access to a few lines of super-premium at the pump with 100 to 102 octane on the old system (and it was relatively cheap). Dial up the timing, fill her up with super-premium and go have some fun.
Thread Starter
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It's my job! 
...Hey Pierre, when are you bringing one of your cars into town? Seems like we planned a tete a tete a couple of years ago??? 
Hi Mike, just don't want the green gum building up over the winter. I run ethanol free Shell premium in most of my seasonal stuff. I trust you're having a good summer up in God's country...
Thanks Joe for that answer. Good news. Bushing and springs should be in on Monday.
...Hey Pierre, when are you bringing one of your cars into town? Seems like we planned a tete a tete a couple of years ago??? Thanks Joe for that answer. Good news. Bushing and springs should be in on Monday.
Last edited by Kerrmudgeon; Aug 7, 2014 at 02:27 PM.
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Summer is going great, have you been in the area recently?
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Static compression ratio is only a fractional consideration in designing a detonation free engine. Anyone who makes a blanket statement as above, has very little understanding of engine design. It is DYNAMIC compression ratio which is the determinant of detonation, along with cylinder quench, intake manifold temperature, spark timing, and fuel octane rating.
As an example, the current 327 which I designed for my car and drive regularly has 11.3:1 static compression, develops over 230 psig cranking pressure, has a VERY aggressive spark timing program, yet runs detonation free on 93 PON pump gas.
Last edited by 65tripleblack; Aug 7, 2014 at 05:30 PM.
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St. Jude Donor '12
Well, I can speak to the issue as to whether the 327-250hp cars needed premium fuel. Several of my friends owned 250 and 300 horse cars. They all rattled on regular, and had to have premium to get rid of the clatter
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The discussion was whether the car needed super premium (100-102 RON) or not.
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It doesn't rattle a bit on E10 89 octane. Years ago, I ran it on the cheap stuff but I don't remember the results.
Of course, the static initial timing is is at 4* BTDC, right where the book says to put it. The working vacuum advance and centrifugal advance curve have never been monkeyed with.
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Thanks,
Doug