Nick I understand you're trying to help but it's about 12 in gear and 16 in neutral.

Make sure the timing isn't retarding or changing when you drop it into gear. It sounds like that's what is happening.

right but if the mixture is to lean it will drop more than it should. the convoter would help alot but it should still do ok the way it is. what do the plugs look like after ideling fo 1 minuet. they should be a tan/brown. i do agree that the convoter is to tight though.

Sounds like:
Initial timing to low
Converter to tight
Possibly a vacuum leak at the intake manifold??

So what is the idle speed? Or you really don't know? If you dont know that and it's not important, change the convertor. You're beign told waht the issue more than likely is. The fact that you havent been able to do it yourself means nothing. I get fresh hands on things I get stuck on too. But the symptoms are the idle is too high, the mix it too lean, or the timing is too retarded for it to make any power at idle. It's lurching because your idle speed is too high for a stock convertor. Not the cam or engine is too radical. There is no reason if that engine is healthy (but stock) and using that cam that it shouldnt be purring along idling at 700 or lower. The stock stall is like 1200. So if it's idling at 900, or 1000, it WILL lurch. Fix the problem. Not the problems it's creating.

All right just got back in from messing with it again....My vac. gauge is screwy but works. Max vac. I get letting off the gas rapidly from 3500 rpm is 17 in and this should be about 22 so I'm assuming my guage reads about 5" low. At 2500 rpm steady in neutral it reads 12.5 +5=17.5 about right. Now it's idling at 750 rpm in neutral, at about 8" of vacuum(guage reads 3 +5), put it in gear and it drops to 500rpm and about 2-3"(guage reads +2) buts it's steady. This is a nice improvement. The timing ATM is way advanced like 30Btdc too much to drive without terrible pinging....I need to back it off now and see if I can maintain the current numbers....

is a freind turning the distributor a lil both ways, while your trying to deteremine if its not getting the correct timming? you can tell if the timming is off . it might help.

I agree with BSB67 - check your mech advance.

What are your timing readings at idle in neutral and then in gear? If it is droping when put into gear, replace advance springs with stiffer ones and retest. Look for the easiest and cheapest fixes first.

Ok now it's idling 800rpm @ 9" in neu. and 600rpm @ an unsteady 2.5" in gear(wavers between 0-5 with engine rpms). Messing with the mixture I can't make the unsteady go away, go any leaner and it stalls and richer doesn't help either.

i was wrong about the Timing, it was actually 10 BTDC and is now 15(ported vacuum no vac. advance at idle)....I may go back to 10 as at least the in gear idle was steady. For some reason this car is doing better than it has in a long time. Thanks for all the help and encouragement.

CONVERTOR, had the same problem with my Hemi Road Runner. Put it in gear it would stall-out tried everything . Then "lightbulb" Installed a nice conv. Its a different car now Idles great, runs better, Now it likes the cam.

I don't think a 218@.050 cam should have a problem idling in even a low comp 440....my 360 is in the 7's for compression, and it idles pretty good with a comp XE262....

my thoughts on what's going on......

the stock dizzy on my 360 started adding mechanical advance at about 650 RPM. so if you're setting your idle at 900 RPM, you're already up on the mechanical advance curve. when you put it in gear and add a load, the RPM drops. when the RPM drops, it pulls out mechanical advance, which reduces idle quality and vaccuum and lowers the RPM...it's a downward spiral until you hit true base timing. I initially set my idle at 950 RPM in my 360, and it'd drop to ~500 in gear, pull an unsteady 7" vacuum and want to die out. I found some stiffer springs to put in the dizzy, so my mechanical advance didn't start coming in until ~1100 RPM, and now my engine idles at 950 RPM with 17-18" vacuum, in gear it drops to ~800 RPM with a steady 12-13" vacuum. I'm running 20 degrees initial advance, and welded up my dizzy mech. advance plate to only add 16 degrees of mechanical advance. the springs I'm using start adding mechanical advance at ~1100 RPM and it's all in by 2000.

WOW! Goin thru my carbs I found an AFB I'm gonna build for this motor. It's a 4329S i.e. a '67 440 HP carb, it has 2 holes in the primary throttle butterfly's!! I bet I can get this carb to purr on this motor......

I think your problem is more with the dizzy mechanical advance than anything else.

Patrick is righ on about what is going on. Put some stiffer springs in the dizzy to keep it from advancing till it's over 1000 rpm. There is no reason you can't have 15+ inches vacume at idle and 12 or more in gear even with the stock low stall converter. It will drop more than a stock lo-po cam but should not be nearly as bad as it is.

PS get a vacume gauge you don't have to adjust for. They are real cheap at most parts stores.

Ok Guys you may be right about the dist. being the issue as the different carb made things WORSE! I thought for sure this carb off a 67 HP 440 with drilled primary throttle plates from the factory would allow this engine to idle decently in gear....well I was wrong it idles worse....the best I can tune it to is about 5" of vacuum @ 800rpm idle out of gear and in gear it stalls. Arrggg I'm ready to throw this 268 cam very far!!! Next time I go mess with it I will advance the timing and see where that gets me.

reread what I posted. it may not be the timing, it may be the advance springs in the dizzy are too light, so you're setting your neutral idle RPM up on the mechanical advance curve. no amount of fiddling with base timing will help if this is the case.

I had this same problem, would have to crank up the idle just so it would stay running in gear, then when I put it in gear it would push against the converter.

The problem was I had the vacuum advance to my distributor in the wrong vacuum port on the carb, some like timed and some like ported.

Play around with that to see if it works better for you, after I switched it over and reset the timing the idle wouldn't drop much at all when putting it in gear.