Hey everyone. Trying to figure out the best kind of baseline configuration to go with for my 383 small block. I've had a heck of a time with it, with the first engine build destroying a rod bearing in the first 4k miles and then having to get lawyers involved so the engine builder would take care of their muck up.

Next up I get the engine re-installed, and it's all quite close, but a lot of little details are off. I'm now trying to really maximize the potential street nature of this car for some spirited cruising. That brings me to the timing on the car.

I'm replace the cap and rotor, since they're about as old as I am (33 years old or so). I've also got an MSD Pro Billet 8572 distributor. I have new springs for the advance ordered, along with the stop on it, and I'm looking for kind of a good baseline configuration, along with how to run the vacuum advance. I checked the vacuum advance with my mighty vac and sure enough it works.

Information about the engine:
383 Stroker Engine Build
Engine Dyno Sheet (Rd2) - 426hp and 437ft/lbs

Comp Cams Shelf Grind Grind # cs-268xfihr13
570/565 lift
218/224duration at 50/1000’s lift
1/13 lobe separation
Stalled at 110degrees on intake globe.

Engine Bored .030 over
Dart SHP Heads, 200cc intake port, 64cc chamber

That's all the info I've got. Dyno says 32 degrees total timing for the testing he performed.

My general questions:

• What's a good base timing to shoot for?
• What's a decent curve to go for with springs?
• Is 32 degrees a pretty safe total timing to shoot for running 91 octane?
• Run the vacuum advance on full manifold vacuum or ported?

Thanks in advance for your input. Trying to get as close as I can on my own for a baseline tune, then hitting up a tuner later this month to dial in the remaining small details and get some dyno runs in to make sure it's at full potential and tuned as good as possible.

 

Question #1: 12* is a good place to start.
#2: All engines act different, testing is the only way to determine which is best for your engine. Usually all in be 3000 rpm.
#3: SBC can tolerate up to 36*.
#4: I run mechanical advance on both my engines, so I'm no help here.
I thought I had a good tune on mine, but had a flat spot. A local shop had a DYNO DAYS car sho so for $50 they ran mine and got 380 RWHP. Made an appointment for a dyno session , they got it up to 411 RWHP and my build wasn't as much as yours is. Yours is going to be a HOOT to drive. T

 

My initial is 22*. Mech'l is 12* all in at 3000 rpm. If you have aluminium heads, your total timing only needs to be around 32* @ 3000. I use manifold vacuum and have limited my vacuum advance to 8*. If its in your budget, invest in a programmable ignition setup and do your own tuning. You can probably do it yourself to get 95% out of the engine. If you need to chase down the last 5%, get a dyno tune. Mine is tuned by me for 91 octane and did three pulls on a Mustang dyno. A best of 357 rwhp with a correction factor applied.