In an NA application, I can't imagine it would make any difference on the time slip.

Chain, gear slop, driveshaft moving around, oil pump affecting the whole mess. Plus cam twist if it's a small block. If you're okay with it moving around a couple degrees, then it doesn't matter.

Crank trigger, what you see with a timing light is like a snapshot. Zero movement.

With the ignition stuff available now, you can set the base timing ahead of where you want it and dial in a retard curve. Some guys I know are using various amounts of retard at different places on the track. No reason it couldn't be done on the street. Even dialing in the timing precisely on each cylinder, if you are collecting data.

Yeah I get where all the "slop" could come from, but does it make a drop in the oceans worth of difference on a time slip? Especially in a motor that's owned by someone who's going to spend money to add a crank trigger (ie fairly tight motor without 100k miles)? I'll wait for Engine Masters to prove it but I seriously doubt it. Certainly not enough to make the cost worth it.

With a crank trigger you can use any beater distributor. The cost yhen is very close. i bought a close out 440 source billet ball bearing unit with no elctronics for $25
Doug

The ATI dampner with magnets is the way to go. I used Andy's bracket that also has a pointer on it. It really cleans everything up nice.

As for why run a crank trigger? Well some engines are that finicky on timing. Some will see decent gains, just by 1/2 degree of timing. Only way to do that is with a crank trigger.

Hint...old Mopar Lean Burn distributors were solid shaft, no advance, spinning a reluctor and a rotor button. Period. Pull the reluctor/plate/guts, and voila, you have a perfect crank trigger distributor.

Probably for free if you can find one.

I spoke with Kent Ritter about this subject just last week. My engine builder is recommending that I go to a crank trigger on our next build . Kent said that is was not necessary for my application . My car is a low 9 second braket car with an alcohol carb.

When is it ever “necessary” ?

Can guarantee with 100% certaintly that if we end up with an extra degree of timing at certain point in a run we will melt parts..But thats what happens when you are in an all out venture. We add timing on a run, a LOT of timing in lower gears. If for some reason we end up with to much in high gear the engine is very unhappy. The amount of fuel we run in the engine combined with its octane and will defintely hurt parts with to much, Yep even a degree or two will kill parts.

It's necessary when you are pulling a lot of timing out (nitrous/boost) to keep the rotor phased or when you have a very timing sensitive combo that you're running on the ragged edge.