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348409
12-31-2011, 04:11 PM
Been running MSD crank trigger system with a 7AL-2 box for several years. Was using a 8984 msd starter saver to retard the timing at start up. Car always started fine. Car quit one night at a big money race and would not start. Took it home and traced it down to the starter saver. Went to a fancy digital start/high speed retard system from msd. Looked good on the dash but engine always kicked back when starting. Tried different retard settings but nothing worked. Sent it back and got a 8982 start/retard box and the same problem. 0,15.or 25 retard doesn't change anything. Problem with the BOX??? Any suggestions??

wmeabates
01-01-2012, 04:47 AM
Check the rotor phasing,if it's off the added retard might be causing it to fire the next cyl in the firing order. Because of less cly pressure it's easer for the spark to go there.Bill.

markdunlap
01-01-2012, 07:42 AM
When using the Starter Saver, there is 2 choices of retard, 10 or 20 degrees. If you were using 10 degrees on it and you have not tried 10 degrees on the new boxes, maybe over 10 degrees retard is too much?

On a 12.5 compression 496 BBC, 10 degrees works most of the time. 20 degrees can cause kick back when hot.

hammertime
01-01-2012, 02:17 PM
Both post above touch on what I'd want to know also

have you phased the rotor and how much timing are you trying to pull out at start up ?

zipper06
01-01-2012, 08:31 PM
Please keep this thread going, i don't run a crank trigger or a starter retard, but we do run a crank trigger on the 66 Biscyne pump gas motor. I just get the engine spinning after the fuel is up then flip the ignation on while running alcohol. I'm learning something here and i'm old but never too old to learn.

Zip.

348409
01-02-2012, 07:59 PM
Coming from an era when a dual point and a 50,000 volt coil was the cats meow I too am getting older. Sometimes I think all this new fangled stuff is a waste of time. Use a drilled cap to set the rotor phasing. Was down playing with it today and looking at the directions for the retard and realized it stayed in the retard mode until 1300 rpm. The starter saver I was using didn't do that. Was adjusting the rotor at idle. Figured it was worth a shot so I moved the dist a few degrees and it started fine. Not 100% sure it will fix the problem but it seems to have at this point. Will be doing some rotor phase testing before the season starts.

hammertime
01-04-2012, 05:41 AM
What size engine is this and how much compression ?

shawnp
01-04-2012, 10:28 AM
Never had any luck with MSD and any product that was to retard the timing for starting. Take it out and don't let it cost you money in a final round.

348409
01-06-2012, 03:38 PM
Engine is a 557 bbc with about 11=1 compression running pump gas. Did have one starter saver go bad and cost me a race. Wiring is set up so I can bypass it if it does it again. Am thinking about trashing the crank trigger and going to a regular dist.

markdunlap
01-06-2012, 03:56 PM
If you are going back to a distributor to get back to some timing advance curve and have less timing at idle, keep this in mind. If you have a Dominator carb, it may need all the advace to run well at idle. Not much booster signal there and a big plenum intake typically.

348409
01-07-2012, 06:03 AM
Idle quality is the biggest reason I run a crank trigger and also why I am dragging my feet on changing. Carb is a pro systems 1100 dominator on an dart oval port intake. Friend has a Dist I think I'll put in it to see if it would work. Thanks for all the replies.

wmeabates
01-07-2012, 06:53 AM
This was more than 20 years ago so there might be better ways now.A friend had a big block crank trigger locked advance dist setup that would crank slow when hot.I put an MSD programmable computer on it and set the mechanical advance back up in the dist to match the computer,still using the crank trigger for the siggnal.Never had any trouble after that,even in the late rounds.I still see that car with that setup now.Bill.

roadkill2
02-20-2012, 10:34 AM
The problem with the starting retard is nothing more than a problem with the little distributor cap . . When you retard the timing to start it fires back to the last (instead of the right one) wire . . Use an adaptor and a big Ford cap and rotor and you don't have the "cross fire" problem and your BBC will start just like a small block with 8 of lead . .

Anyway, that's what we do . .

TheRabbit
02-20-2012, 02:21 PM
The problem with the starting retard is nothing more than a problem with the little distributor cap . . When you retard the timing to start it fires back to the last (instead of the right one) wire . . Use an adaptor and a big Ford cap and rotor and you don't have the "cross fire" problem and your BBC will start just like a small block with 8 of lead . .

Anyway, that's what we do . .

I used the small cap for a year or so. Was scared to death to use it with nos so I finally swapped it out.
MSD calls it a Cap A Dapt. You will have to pull the dist. out and reset it on #1. I wish I had swapped mine a long time ago!!

wmeabates
02-20-2012, 03:17 PM
Roadkill,When the spark retard delays the spark the rotor has passed the cyl it was to fire.The spark goes to the next cyl in the firing order that has just started to compress.full of air fuel mix and about 100 degrees BTDC causes the kick back.Big cap allways a good thing with high compression. Bill.

roadkill2
02-22-2012, 08:19 AM
Roadkill,When the spark retard delays the spark the rotor has passed the cyl it was to fire.The spark goes to the next cyl in the firing order that has just started to compress.full of air fuel mix and about 100 degrees BTDC causes the kick back.Big cap allways a good thing with high compression. Bill.

We found that it was firing back to the one it had just passed on full retard . . but a little study of what was available and why, problem solved . .

Another thing about the "Big Caps" vs. the little ones . . with the high energy coils we use today, a little cap can (and does) have a literal lightning show going on inside at high RPM . . Things are just too close . . and with crank triggers, where the rotor is can be a moot point . .

wmeabates
02-22-2012, 09:52 AM
Roadkill,We arn't clicking on this.When the timing is retared electricly it makes the spark later,the rotor is still moving. So too much retard and it goes passed the cyl it should fire.If it fires back it,s firing the cyl it should.If it fires the next cyl in rotation,kick back. Due to less pressure it,s easy for the spark to go there.IF it would fire the cyl that was allready passed tdc there would be no kick back.Bill.