daves66valiant
68 Dart 340/727:66 Signet Vert 340/5spd: 68 D100
Engine specs might help first huh.
360 Compression is probably 9.5-10.0
650 carb
242/246 duration cam with .510 lift @ 50
Rpm performer intake.
Stock manifolds right now but will have headers soon.
Well, I finally got a timing light on the engine. The PO took the car to a shop to get tuned. They had the initial set at 11* which seems low.
I have never worked on MSD dizzys before but I'm trying to understand them after reading the directions online. With the stock MSD 21* blue bushing that didn't get changed out, I'm thinking the total is 32*. It has light blue and light silver springs in it right now. The chart says it should be all in by 2300. I forgot to see when it was all in by. This car needs a few more degrees of initial from what I've been seeing from other people with higher lift and longer duration cams. 18* initial is the number I got from somewhere I read.
Question: So if I put the black 18* bushing in the msd dizzy and the set the initial at 18* then I should get 36* total right? The approx advance curve charts from MSD say my timing should be all in by 2000. My cam does not start producing power until 2800-3000. I would think I need the advance curve to be a little slower right and coming in later around 3000-3400 rpm? Is there some good literature out there for performance advance curves? I'll keep searching since I'm still trying to get a handle on this concept.
360 Compression is probably 9.5-10.0
650 carb
242/246 duration cam with .510 lift @ 50
Rpm performer intake.
Stock manifolds right now but will have headers soon.
Well, I finally got a timing light on the engine. The PO took the car to a shop to get tuned. They had the initial set at 11* which seems low.
I have never worked on MSD dizzys before but I'm trying to understand them after reading the directions online. With the stock MSD 21* blue bushing that didn't get changed out, I'm thinking the total is 32*. It has light blue and light silver springs in it right now. The chart says it should be all in by 2300. I forgot to see when it was all in by. This car needs a few more degrees of initial from what I've been seeing from other people with higher lift and longer duration cams. 18* initial is the number I got from somewhere I read.
Question: So if I put the black 18* bushing in the msd dizzy and the set the initial at 18* then I should get 36* total right? The approx advance curve charts from MSD say my timing should be all in by 2000. My cam does not start producing power until 2800-3000. I would think I need the advance curve to be a little slower right and coming in later around 3000-3400 rpm? Is there some good literature out there for performance advance curves? I'll keep searching since I'm still trying to get a handle on this concept.
