I have a 71 383 with a 70's Holley 4bbl
MSD 6pal ignition
Comp cams
Tube Headers
tci streetfighter 727

My question is where to put my timing.

a)I've see on the net 33-38.  However my marks only goto 20.

b)Right now I have no power at my bottom end rpm range, only really kicks in after 4000 rpm.

How do I set the timing, at idle?  At idle with no vaccum.


Any help would be great, as I am just starting out dealing with carb-systems.  

You will need a good timing light to set the ign. timing properly on any car.
With the vac. advance disconnected set the initial timing to 12 degrees, this will be close, and give you a good setting to start from.
With that rev. the engine to 3000 rpm in park of course.
Check you total timing of the dist. by advancing the dial on the timing light until it reads zero on the engine timing mark.
Now check the ready of the timing light, it will likely be around 35 degrees total. If the dist. is working properly that is.
If not check the advance springs on the dist. and do your self a favour. Install a vac. advance line from the dist. to the carb, its got to be worth 5-6 miles to the gallon when cruising.

Dr. Mopar  

Dr Mopar...

Thanks,

I have no vac advance connected on the msd distributor.

The timing light I have has no dial, I take it I need a better timing light.  


what do you mean by
"Now check the ready of the timing light"

also, the carb has a small vac hose that has been left open to air.  I've blocked it off, but it still does nothing for me in regards to power.

my first run was 13.55 1/4 mile.  Now im sittin at 17's!!!!

All this im trying to sort out from a prior owner....  

i think he meant reading not ready and yes you will need a timing light with an adjustable dial or digital read out or some timing tape is the cheap way to go right around 34-35 degrees has worked great for me if you know the size of your balancer i can tell you the measurement from the tdc mark and you can mark the balancer and use your timing light  

I had the same timing troubles, all I did was reved it up to 3000 rpm and adjusted the timing to where it sounded the best lol... all this degrees stuff had my mind in a twist  

These adjustments will be easiest with a dial back timing light.  I recently performed the same timing adjustments (12 degrees BTDC with vacuum plugged at idle) and mine is working perfectly (although I'm using a Jacobs pro street ignition system with standard stock vacuum distributor).  With the dial back light you can pull the spring off the throttle and manually check timing throughout a fixed rpm range.
You have to plug the vacuum on the carb.  You can get plugs at any auto parts store for a couple of bucks.  You definitely have to plug any open vacuum ports on the carb.
Good luck  

oK,

Once again I tried to set my timing, all vacuum lines pluigged

12 BTDC
once I revved it up past 3000 and back, the timing hangs back down at 22 BTDC, despite a number of tries, set at 12 BTDC at idle and torquing the hold down bolt right down....  after each time I rev it up. it jumps the BTDC to about 22!


Whats wrong?  

Just so I understand...are you saying that the timing is set at idle to 12, then revved up to 3000 it goes to 22...then you move it back to idle and it hangs at 22 and never goes back to 12?
If this is the case (sticks at 22 at idle that is) then you may have a bad spring or something hung up in the mechanical advance in the distributor (usually there are springs connected to weights in the distributor...at higher RPM the weights spin out from the center and advance the timing...which you need at higher rpm for a proper fuel burn.)  If this is not it I would suggest that you "google" mechanical advance ignition systems...there is a lot of info out there that will help you debug it.  There are a couple of good books out there too, I recommend "Performance Ignition Systems" by Jacobs. Awesome read on ignition systems!  

No it sits about 33 at 3000 rpm

Then sits about 22 after. reving up.  After I set it back to 12 rev it again, it goes back to about 22.  

sounds odd but you probably have a problem in your distributor a spring gummed up or something  

id also try and get the idle at 3000 a little closer to 35 sounds like the centrificul advance isnt returning all the way after rev prob needs new springs or adjusting most msd distribs are adjustable  

I agree, it sounds like a spring is bugged that handles centrifugal advance in the distributor (it almost sounds to me that one of the two springs for one side is unhooked).
At idle mine is about 12, rev it up to 3000 rpm I show about 37, then down at idle it is 12 again.  The advance moves linearly from idle to that 3000 rpm level from 12 to 37.
This website has a great pic of what centrifugal advance setup looks like (paste full link in browser address line):

http://www.raceservice4u.com/Twin%20plug.htm

Good luck and let us know what you find...  

Another good shot at this...

http://www.vintagecarparts.biz/English%20information/Technical%20infomation/45d-ignition/working-ignition-system-uk.html  

Wow, what ever you do don't guess.
After reading all the advise I would suggest a simple fix, if you don't have a proper timing light take it to your closest garage, they won't charge you more than half an hr. to set it up properly and if there is a problem with the dist. they can advise you accordingly.
Dr. Mopar  

P.S. make that a reputable garage for some good advise.