I was hoping I could get some ideas on tuning mine for better off the line performance. 74 Charger, 400hp auto, 323 rear. Car is bone stock with the exception of a 750 vac sec holley and an edy dp4b intake I just added replacing the thermoquad and stock intake. As delivered jetting in carb with no bog, timing set at 32 total with light springs in dist and no idea when it all comes in at. Car takes off sluggish then rolls out 20ft or so and starts pulling descent, both carbs have acted the same. Any ideas would be great! Thanks Moparts!

A couple of things to do..
1. Increase the shooter size to 0.031
2. Increase timing to 35 degrees
3. Liten the Holley secondary spring
4. Make sure the accelerator pump is set rite

Just my $0.02...

Get your timing curve sorted out first. The low-cr smogger big blocks are very sensitive to this.

You'll want to play with your distributor curve. Remember to set it up first with the vacuum advance disconnected and plugged at the intake. I set mine for as much initial timing as it would take while still being able to restart hot. With a smogger 440 with a lunati voodoo 60303 cam and 440source heads it liked near 20* at idle and I set it for 38* total in by 2500rpm. Not too much longer after that it wouldn't want to restart hot, I thought I had too much initial timing(turned out to actually be a charging system issue), so I backed the initial timing back to around 15. Could not get rid of that initial launch bog until I figured out the problem was my charging system, not too much timing. Bumped the timing back up and the bog was gone again.

With a stock cam and heads, you won't need as much timing as mine did, but I would still start by figuring out how much initial it will tolerate, then dial in your total from there.

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X 2. in order: initial w vac gauge method, w that figure in hand shorten the slots to get 35 (SB) w vac adv unhooked/plugged. Springs-toss the heavy one w the long loop & start by adding one of the very light ones in the MP cellophane pkg & want to stay just under the pinging point at WOT up thru the gears on your hottest/driest day no matter where (RPM) that makes the slots max out at. then plug in the vac adv & want (A) the most adv coming in (B) as fast as it can (2 adjustments) WO pinging at steady PART throttle (high vacuum) at an RPM at or above where the slots (mech adv) is all in. EDIT it's a BB so 36-38 for total (vac adv capped)

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Thanks, I'll play with the timing this weekend and see if it helps. When you say shorten the slots do you mean the slots for the advance in the distributer?

Did you alter the slots in yours or just play with springs?

I had an aftermarket distributor so the advance was a bit easier to adjust than a stock distributor. I think somewhere in the archives is a chart showing how much to shorten the slots in a stock distributor to get your desired spark advance.

Indytex96, I'll work with you because I have a 400 and am about to do the same thing this weekend. I just got my spring kit in the mail yesterday. Unfortunately, it's raining like crazy this weekend but I can do the prep work in the garage.

With my 400 and 3.23 gears, it was a slug using total timing in the 30s. I'm running a total of about 50 degrees and it's great.

Great feedback! So it sounds like Indytex and I should not weld up our slots, just replace the thicker distributor spring with a thin spring from the Mr Gasket kit 925B?

Trial and error is the only way. Mine would ping if I tried to put 50* total (not including vacuum advance). And I had a wideband o2 so I knew I wasn't lean.

Stock 400 right? Use the Mopar perf dist with the adjustable vacuum advance.Tune per the instructions.No reason not to use it with a stock engine.