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Posted: Tue Mar 05, 13 4:51 pm
by db
Pete wrote:You will have to find a way of doing this if you are going to use that dizzy; hence my comment about a welder earlier...in essence, the slots are too long....
Like so...!
http://www.moparmusclemagazine.com/tech ... to_13.html
This article also mentions the limiting plate is marked in dissy degrees, so it's doubled to equal crank timing before adding to initial.
I've just done a check of my mech advance by locking the dissy shaft gently in a vice and turning the advance plate under a protractor.
The first 9 degrees (9 x 2 +17 = 35) comes in before the stiff spring contacts, then the limit plate stops it at 13 degrees (13 x 2 + 17 = 43)
If the total I require is 35 then the strong spring will be redundant as I'll need to stop advance at just the point that makes contact.
So I'm thinking a slightly shorter strong spring AND welding the limit plate slots.
Posted: Tue Mar 05, 13 5:00 pm
by Pete
Yep.
Or lock the timing out, and use an MSD and Starter saver
Works everytime for me
Sorry

Posted: Tue Mar 05, 13 5:52 pm
by Pete
To explain.
Use an MSD - Digital 6 is best but could use an AL6.
Wire the MSD "ON" separate to the "Crank" circuit. You can use the White wire as an anti-theft device as well.....
Lock the Dizzy solid. Welding is cheap and nice. Remember to phase the distributor first.
Base time motor to 15 degrees.
Get the motor running [head out on the highway, looking for adventure...]
Warm it to operating temperature.
Set timing at 3000 rpm to 34 degrees.
Turn motor OFF.
Normally the car would NOT start from hot or cold at 34 degrees.
Turn the MSD OFF.
Crank the motor.
Switch the MSD ON whilst cranking.
The car will start.
Back Idle down as it will race.
This worked on a 12:1 compression motor.
If engine does NOT start like this, buy the "Starter Saver/retard" component for the 6AL. It is integral to a Digital 6.
It will automatically take 20 degrees of timing out below 600 rpm.
This equals 14 degrees at cranking speed, and the motor will start easily.
Simples.
Just add money....
See other thread you posted for refernce re: Poverty.....
Posted: Tue Mar 05, 13 8:13 pm
by db
Thanks, I was just thinking of asking you to explain...
Only thing I don't get is "phase the distributor" ?
Posted: Tue Mar 05, 13 8:17 pm
by Pete
Make sure the Rotor arm is directly aligned to the Cap tower when the pickup rotor is aligned to the "nub" of the ferrous 8 pointed rotor.
Drill a hole in a cap to make sure it is aligned before you take welder to Dizzy....
Or you could go for a crank trigger device

Posted: Tue Mar 19, 13 2:46 pm
by db
I'm done playing with my milling machine for a bit, so I put my dissy back in and fired her up.
Initial timing now seems happiest at 22 (revs level off here as I rotate the dissy). This now gives a total advance of 35.
Idle is 850-900, vac at idle 5.5, AFR gauge shows 14.5-ish, it starts fine and idles reliably.
Going out for a spin now to warm the engine through so I can do the hot valve clearance check.
Posted: Tue Mar 19, 13 2:51 pm
by Pete
Sounds in the ballpark.
Good luck on the "Warm up"

Posted: Tue Mar 19, 13 3:05 pm
by db
I forgot to mention I welded the timing slots as you suggested Pete, so that's the absolute max timing it'll reach now.
And of course I managed to refit the dissy 180* out so got a nice backfire and flames out of the carb.
Reminder to self... CHECK EVERYTHING!!!!!
Posted: Tue Mar 19, 13 3:32 pm
by Pete
Posted: Tue Mar 19, 13 4:37 pm
by Guy
Posted: Tue Mar 19, 13 5:24 pm
by Les Szabo
db wrote:I forgot to mention I welded the timing slots as you suggested Pete, so that's the absolute max timing it'll reach now.
And of course I managed to refit the dissy 180* out so got a nice backfire and flames out of the carb.
Reminder to self... CHECK EVERYTHING!!!!!
Glad you got it all sorted, now comes the fun part, enjoying all that extra power now its running on song, and you still got the carb to go..
Don't forget if you bolt on an N20 kit Paul to reduce your timing by a degree or 2 if you plan on running any more than 150 shot...depending on your CR and the fuel your using.
Les
Posted: Tue Mar 19, 13 5:38 pm
by db
Funny bugger
Actually I've just put a 4.5pv in and the big hesitation off idle has all but gone
The AFR still goes up to 16-17 on acceleration and at steady speed.
I've just got a pump cam set so I'll play around with those and it must need upjetting.
How do I disable the secondaries- is it a simple mechanical stop-the-butterflies-moving job or is it more involved?
Posted: Tue Mar 19, 13 5:40 pm
by db
Les Szabo wrote:db wrote:I forgot to mention I welded the timing slots as you suggested Pete, so that's the absolute max timing it'll reach now.
And of course I managed to refit the dissy 180* out so got a nice backfire and flames out of the carb.
Reminder to self... CHECK EVERYTHING!!!!!
Glad you got it all sorted, now comes the fun part, enjoying all that extra power now its running on song, and you still got the carb to go..
Don't forget if you bolt on an N20 kit Paul to reduce your timing by a degree or 2 if you plan on running any more than 150 shot...depending on your CR and the fuel your using.
Les
Ta

That won't be for a little while...
Posted: Tue Mar 19, 13 5:46 pm
by Pete
Cable tie or paper clip will do the job if you are minded to take it any further.....
Posted: Tue Mar 19, 13 6:48 pm
by Dave-R
db wrote:
The AFR still goes up to 16-17 on acceleration and at steady speed.
I've just got a pump cam set so I'll play around with those and it must need upjetting.
How do I disable the secondaries- is it a simple mechanical stop-the-butterflies-moving job or is it more involved?
Get the jets right first. Then see if the pump shot needs adjusting. Remember the pump shot only lasts a few seconds so is only for any initial bog. With vacuum secondaries and a correctly spec'd power valve you shouldn't need much pump shot at all.