mclarkphotos 11-22-2010, 03:30 PM I may be asking an over asked question, but I might just be missing it..
Combo: MSD 6AL, MSD Coil, MSD Pro Billet distributor without vacuum advance and MSD wires (all new items). Engine is also Edelbrock performer single plane intake with Edelbrock card.
Question: Where is a good starting point and max for the timing. I'll be hooking up the timing light for the first time. Car starts up pretty good, but sucks from 1800 RPM to 2500 RPM then runs solid from there.
I know I may have a carb issue, I just want to make sure timing is correct before I start pulling vacuum measurements and tearing the carb apart.
Thanks,
Meep-Meep 11-22-2010, 03:48 PM Regardless of ignition system the total timing on a BB MoPar is 36-38 deg (32 deg for HEMI). Set the mechanical advance so it's all in by 2200 - 2500. You may find a happy place for the initial to be 10-15 BTC. Vacuum advance should be hooked up on the ported port on the carb and as a rough setting should add 10 deg when a vacuum signal is present. This 10 deg goes away, or should go away, under WOT.
mclarkphotos 11-22-2010, 07:09 PM Just finished checking the timing (I don't have a timing tape), but it's around 12-15 BTDC. It doesn't have vacuum advanced and when I went up to about 2200 RPM the timing didn't change. This would explain why it's not running real good. Anyone have some pointers about a MSD Pro Billet distributor and the timing curves?
Manifold 11-22-2010, 07:54 PM http://www.msdignition.com/instructions/Products/Distributors/8546.pdf?terms=advance%20curve%208546
According to the instructions, MSD sends those distributors out with heavy/slow springs. If you haven't already, I'd suggest reading through the instructions. You'll need to get some parts to bring in the curve faster.
Stumper 11-22-2010, 07:59 PM Did your distributor come with the kit of springs and bushings to "curve" it? It has a few different sets of cam springs to regulate how quickly the cams open and the bushings determine the amount of advance the distributor will make. If not you can buy the kit from Summit.
Meep-Meep 11-22-2010, 08:20 PM How about first checking to see if the rotor moves freely and springs back?
Manifold 11-23-2010, 12:07 PM How about first checking to see if the rotor moves freely and springs back?
No doubt! Ran into a GM HEI which was so gummed up on the inside (the grease/lube on the distributor shaft and housing was so old and sticky) that if the mechanical advance managed to engage/move, many times it wouldn't reset/return to base timing when the RPMs came down. I scratched my head over that one a bit before figuring it out... using the above method. :)
Dennis H 11-25-2010, 03:16 PM My 440 was balky and had to be coaxed for years. A friend installed a kit in the distributor and it runs like never before. It romps at 750 rpm. No balking or coaxing needed. The best $37.00 ever spent. I have a similar set up.
MSD AL, Edlebrock RPM, 850 Demon etc.
www.4secondsflat.com
Get an MSD Bushing Kit. Install was tricky but worth it.
$29 puls shipping
FBO Systmes
541 942-5920
Parts are Made in USA
daredevil 11-25-2010, 10:12 PM I would start out with one of the springs that come in it and a light one . Cant remember if its blue or silver. Then install the black bushing. Its an 18 degree advance limit. Time at 18* btdc at idle under 950 rpm and when you rev it you should jump to 36 *btdc. my 500 runs pretty well like this and its on pump gas.
SUPERSTOCKRACER 11-28-2010, 07:34 AM I would start out with one of the springs that come in it and a light one . Cant remember if its blue or silver. Then install the black bushing. Its an 18 degree advance limit. Time at 18* btdc at idle under 950 rpm and when you rev it you should jump to 36 *btdc. my 500 runs pretty well like this and its on pump gas.
I AGREE. start with 1 silver and 1 blue with black bushing.
beezee 11-28-2010, 08:36 AM I AGREE. start with 1 silver and 1 blue with black bushing.
My 496 is running the same silver, blue spring with black bushing,idles at 850 RPM,starts once warm with out even touching the gas .
watermelon 03-26-2011, 04:57 PM Hi all,
I see the 1 silver, 1 blue, with black bushing combo mentioned a few times here.
Is the silver a "heavy" silver or "light" silver?
The blue springs in my MSD kit at light ones.
I just finished up a conversion from points to an MSD 6AL Box, MSD Pro Billet Distrib, and MSD Blaster 2 coil combo in my 440. The engine fired right up.
I don't have a tach so I cannot look at RPMs. I do have an old Actron Engine Analyzer which I'm tryin to figure out how to use; it has an RPM setting.
watermelon
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