matts86cam

iTrader: (1)

It would be on the road if I knew which vac advance distributor to get.

this isnt a race car just a trailer park ferrari so I dont need anything extreme just something with decent performance and reliability.

I have no idea about setting the advance curve really so i am looking for one that i can just drop in.

I have to retard my
(reman'd but dont know how it runs yet cause I did the swap myself) 355sbc 10-12 degrees.
I still have to search a little more (on TGO ) for setting timing but I thought I would point it at TDC #1 and rotate counterclockwise about an inch and see what that does.

The car is an 86 z with edel. 650 and a hyd. cam (lopey idle supposedly) 9.7 : 1 comp.
I dont know what i should list in order for you guys to make a good suggestion

305sbc

iTrader: (3)

MSD #8361 distributor w/vacuum advance.

Generally, a good place to set initial timing is between 5* and 10* degrees of spark advance.

If you use 10* initial and you want 30* total advance at WOT, then you will have to limit your centrifugal advance to 20*. Most distributors use bushings to limit centrifugal advance. Larger bushings give less advance. Some distributors use metal tabs as stops for the centrifugal advance mechanism. Bending the tabs inwards gives less advance. Whatever the method for setting centrifugal advance, you use a dial-back style timing light to measure it.

Total advance is the combination of initial advance + centrifugal advance. You can juggle the values of each to a certain extent to get the total value that your engine wants.

Vacuum advance is normally best limited to + 10* at idle. All vacuum advance mechanisms can be adjusted or limited, though stock units require modification to achieve this. For performance applications the vacuum advance is is connected via vacuum hose to a manifold vacuum source that provides high vacuum at idle or coast (low load conditions), and low vacuum at WOT or accelerating (high load conditions). In this situation you do not add in your vacuum advance value when determining your total spark advance, because the vacuum advance unit should not be adding any advance during WOT.

Distributors are NOT made to be drop in pieces without adjusting to your particular application, use, and preferences. You will need to learn the procedure or recruit help for the process. Guessing at your spark advance settings is a sure way to fail, and can result in major engine damage.

matts86cam

iTrader: (1)

The guys that built the engine said to retard it 10*
With that in mind, a OEM dissy has around 20* centrifugal advance so I would only be advancing the spark by 10* at WOT right?

Cant I just use the one that I ran the 305 with, time it by ear and be finished with it? Do you think it would damage the engine as long as I timed it right initially and last one... would it ***k my engine up if I just used the dissy i have long enough to break the new engine in and get it to a shop?

ATX-Iroc

either they accidentally got their words mixed up or your memory did but i think they said set the initial advance to 10 becuase I seriously doubt the engine would run with 10 degrees btdc. And just get the right distributor, do it right the first time. the accel dist they sell at auto parts stores isn't that bad, I've used a couple and they work decent, no complaints.