I am considering using an MSD timing computer (its actually an early model to current start retard)

I picked up as a swap - the programmed curve has a start retard and then gets up to teh set mechanical timing by 3000 rpm - provided you use a crank trigger or locked out distributor

I downloaded info on MSD 85551 distributor (some of you may recall that I have had distributor advance problems) which can be locked out but my unsolved query is

How do you set the total timing when the distributor is locked out - do you use (at least what was taught to me) the method of bringing it up to 3000 rpm and spot the timing light

Seems obvious but the fact is I need to know what I am facing

Thanks

if the distributor is locked out, then whatever your base timing is will also be your total advance- which seems screwy to even type because there is NO advance to speak of..

You'll need the info from MSD as I believe like modern electronic engines you disable the centrifical advance and set the initial to a pre-determined setting and the computer does the rest based on what it is programed to do.

bring your rpms up to 3500 and set your timing at 34-36 or whatever you plan to run.on my hei dist i had to weld the weights so the computer did all the work,retards 20% at start up.on msd dist i think they have screws so you can lock you dist.call msd tech line they helped me alot when installing mine

Jaw 2 - this welding up of the advance weights on the HEI is an interesting cheaper alternative to buying the new MSD distributor

The reason I was going to get the MSD distributor was because it has the lock out option which will allow me to use the computer

can you give me some more info. on converting my Accel HEI mech. advance distributor to a locked out one ??

I would be really keen to hear

T.K.

you COULD just get an HEI out of an 80's car that had a computer controlling the timing- they are already "locked out". they are available with either the fullsize HEI cap and rotor, or a smaller version with an external coil.

Just remove the advance weights and reinstall the springs. No more advance! graemlins/beers.gif
David

on mine i had to take the modgulars out (per msd instructions,you don't use them),then we just tacked the advanced weights so the computer did the work,what model computer are you going to use.the one i had was a msd 8980

Jaw 2 - mine is the very same 8980

The guy that had it used it only as retard so he told me he had a start retard box - which is what I really wanted

Now I downloaded the instructions I see that the start retard does not work unless you are using the programmed timing curve

with all my prior sticking advance weights problems - I thought why not use the computer since its there

If its as simple as removing the weights - I do have a Accel racing mechanical HEI - no vacuum advance - but the advance started playing around

then I can install everything this weekend

Thanks

by taking the mogulars out of my dist and and tac weld the weights the computer did every thing,if you need a dist already set up i took my out (when i put a blower on) i'll sell cheap.it's a hei i got with my 509 merlin,