KDW

Hello all wanted some good advice on setting up a MDS in my 72 olds with 455.

Here's the scoop!

the car has an HEI in now I'm exchanging with READY TO RUN MSD! my car had Edlebrock heads, lunati 60803 510 522 lift, edlebrock 1910, 308 gear.

i need to know if i should lock timing out at 36 (will this may car run hotter at idle)or just set up with vacuum and which bushings to use. I have the option to use msd box and coil also.

Thanks

oldcutlass

I would not lock the timing if you are driving on the street.

Run to Rund

Don't lock timing; it would be hard to start hot and would tend to kick back and break the starter. Use bushings and springs for 12 deg. initial, 36 total. Vacuum advance helps it run cooler and improves fuel economy.

oldcutlass

I would set the distributor up so you have 18-20 initial and a total 36-38 total@2500 rpm. Use manifold vac on advance can. limited to 10-14 degrees.

KDW

KDW

this is what im working with, dose fig D or E look ok ?

KDW

im thinking the black or purple bushing any thoughts ?

oldcutlass

I'm thinking figure E with blue or black bushing.

cwb442

I use figure D with black bushing. Black allows only 18 degrees of advance and will allow you to run the most initial timing. So I set mine up at 18 initial and 36 total. I'm going to try and up it to 20 initial only because I think it would idle even better but that's me. Also I've got 240 duration to that's why but I've always want to get the most initial time I could just seems to idle better. Another thing I tried was graph E the black bushing and encountered some detonation it just seemed like total timing was coming in to soon. But I also am running 91 pump gas and iron heads with 9.75.1 comp.

KDW

Ok I'll let you now what happens Sunday or Monday. I installed black bushing and two blue springs, if it likes that I'll got lighter springs (silver and blue) thanks for all the help

distributorguy

The more compression you have, the less total timing you can run without detonation. Have you done a compression test? What are your cylinder pressures? Are your heads stock, modified, or aluminum? Are the combustion chamber shapes modified? The more efficient it is, the less total timing you need. The larger the carb, the more initial timing you need to overcome velocity issues with fuel metering. Too many unanswered questions to be able to recommend an accurate timing curve.

KDW

I have not done a compression test, it dose have edlebrock heads, I don't think any porting. I put black bushing in 10 min ago set timing at 18 with two blue springs, no hard starting although I have not driving it (just pressing drake and gas can't hear anything) I set it at 20 initial sounds great wants to lite tires.

No noise no hard start?

KDW

I'll warm it up and do compression test let you know
It's not a new motor so hopefully it's decent! What should it be

KDW

Just looking at chart if there no pinging should I go lighter (blue light and sliver light) man this thing likes timing

KDW

So did a comparison on some not all got 150 152 range did not pull all plugs just bumped over with a guage hot this helps

z11375ss

I have a MSD billet (so I know things are a BIT different) and went with diagram F. The car revs so quickly with this setup it's hard to shift fast enough. Did this to my Vette that was laying over when you mashed the throttle. Same results. Revved extremely quick. Very satisfied. Good luck. I tend to go with the hottest setup and backtrack from there if the motor doesn't agree. You can dial these things in so precisely you can't believe it.

distributorguy

One blue, one silver should put you around 3000 rpm all-in, despite what the chart says. Use a black bushing and give it as much initial as you can. Chart E.