Going to have a prestolite dual point tach drive set-up at the local speed shop but unsure what exactly I need. Normally I run aftermarket distributors that I can play around with springs & such so not sure what to tell them I am looking to get it set at. I am not sure how much advance that distributor has but probably just want it all in at 2800 or so.

I’m open to any advice & here’s the set-up:
3090lb ‘67 Barracuda
3600 stall w/3.55 gears & 26” tire
440
Edelbrock performer heads
850 DP Holley
Weiand Single Plane
Cam Grind Number: XS282S
Advertised Duration: 282 int./290 exh.
Duration at 050 inch Lift: 244 int./252 exh
Lobe Separation (degrees): 110

You can do it on a wheel dyno IF it’s not an inertia dyno. You need to be able to load the engine, steady state at WOT to develop your timing curve.

Getting it all in as quickly as possible has always worked for me. The lightest springs usually on function as a retard to make starting easier. Once the car is started all timing is in at idle.

iagree 25* initial and all in by 1,800 at the very least.

So why not lock it out and be done with it?

Good luck. It will cost a bunch of money to have a shop build you a custom curve. You'll actually have a hard time even finding a shop with a distributor machine much less someone who knows how to run it. We refuse to custom curve distributors anymore since it can take several hours to do it correctly. If you charge the customer $100 per hour for 4 hours of work they freak out, especially if they bought an old distributor for $50 at a swap meet. It is a lot less expensive to buy a digital distributor and program it with your laptop or cell phone.

Fact. It takes a long time to sort out a timing curve. Then getting the distributor to do what the engine wants is another story.

Most engines I see want a bunch of initial, almost no advance through peak torque and then a curve to peak hp. Quick curves and locking them out generally kills power at and around peak torque.

Agreed. Once you find timing that makes max hp, you can pull several degrees at max torque without reducing output and then ramp low rpm up to max torque timing. Not happening with just centrifugal advance.

While all that may be true, here's the reality: a warmed up (hot) 440 in a 3100lb car with a looser converter than stock and 3.55 gears will get along just fine without the timing curve set perfectly. The idle and off idle timing will be the most important areas to the driver. After that, the engine will pull basically the same where ever the curve is set. A dyno may show some slightly different numbers, but the OP's butt dyno will never tell the difference in curves. And if the driver is pushing the throttle hard, the converter will flash to 3,500RPM anyway. Unless the OP is running drag radials, the traction will already be compromised, so a little more torque from a perfect curve won't help anything.

The cost to dial the curve in perfectly will not be worth the money in this combo. That money would be better spent somewhere else. If the OP starts with 25* +/-, we are talking about 8* or so through the curve. Not enough to kill power. It may loose some torque, but with an abundance at hand given this combo, it won't be noticed.

Thats a lot of money for it

Not when you don't have to buy, mount and wire an MSD box and distributor. Just one distributor and 2 wires to a coil and a hot. I have set up 5 or 6 of them on the dyno, and they are impressive.


Joe