MSD Pro Billet Dist. Which bushing and springs recommended

[2ndgear]

What I got is a 445 in a 1969 mustang. I would like to know what springs and what bushing I should start with in the dist. The engine was dyno at 540 hp and 548 torque. That was at 16 int. and 36 total. That is what it seem to dyno the best at.   4 speed car -389 gear-ported edelbrock heads -performer rpm manifold- headers -294 solid cam. -28 inch. tires.  What springs and how quick do I want the advance to come in. I am thinking Blue bushing and 2 Blue springs.  Any thoughts   And thanks in advance

[351crules]

i'd lock it out if you have a start retard...if not black bushing and light springs.. but thats me

[1968galaxie]

I would certainly start with your suggestion - if you were wanting to stay with 16 initial and 36 total.
Blue bushing (or possibly purple) and the 2 blue light springs.
Should have full advance around 3000 rpm.
The springs and bushings are easy enough to change.
Have fun, see what works best for your application.

[2ndgear]

It seems to run good at 15 to 16 initial and 36 total. I guess I could try the black bushing and light springs but I would have to change the initial to about 18, so I would end up with 36 total. With the 18 initial and the light springs I am wondering if that would be to fast of a advance which may cause detonation?

[My427stang]

Stout Edelbrock headed 445!  Likely would be able to help for with more info, compression, cam, planned fuel, use etc.

However I am surprised it liked 36 versus 38+ but it must have decent compression and tight quench.  Typically, I go for  run 14-16 initial, but nothing wrong with 18+ if the starter can handle it hot.  Spring it to get it all in by 3000 and you are being conservative for fuel, but not so conservative it will build heat.  It likely would be very happy at 2700 or so and some vacuum advance on top of that.  However, as I said, more info will help steer you

In my 489, 10.7:1, Edel heads, pre-EFI I ran 14 initial, 38 total, all in at 2750, now it fires at 10, and immediately goes to 20 then has sort of a 3D curve, so hard to compare, but your current thoughts look good.  Check back with more info and we can tweak it

[2ndgear]

On my paper work I have it says 72 cc chambers 2.09 intake and 1.66 exhaust, seat 128, open 370. comp 294s cam, compression ratio 11.27, quench .046 93 octane, car street used. Mechanical advance on dist. When we dyno it it did like 36 better then 38 for some reason. Hope this helps Ross. Thanks for your time.

[Barry_R]

Most of the ones we do on dyno get black bushing with one "light" silver and one blue spring.  Blue bushing if it requires less initial to start. Two blue springs if it rattles at light part throttle.

[My427stang]

I am about the same as Barry.  However, I'd go the 20 degree blue bushing, set at 16 initial. 

As far as springs, I agree with him completely.  The light silver and blue is a nice combo and should get you in around 2800, the two light blues will get you in at 3000.  My gut says, if you manage engine temp and aren't running lean, with decent gas, the light silver and blue will be the right combo, but you are right on the edge.

I would check it afterwards though and make sure it is matching the planned rate

[Falcon67]

i'd lock it out if you have a start retard...if not black bushing and light springs.. but thats me

That's me too - 10 degree at least start retard, lock that sucker at 36.

[2ndgear]

Thanks guys
I will start with the blue bushing and 1 lite silver spring and 1 lite blue spring and see how it runs.