Heres one that might stump you.

[quagmire]

This also would explain why you had issues bolting the flexplate to the converter.  If it was bottoming out in the crank that might be why you had to bend the mounting ears on one of those flexplates to get it to work.  I cant remember what mine looked like, but that does seem a lot more shallow than my crank.

[tactransman]

You know now that I think of it,I had another customer that was having problems like you are having and he also had an 8 bolt crank flange(Aluminum Keith Black Hemi) he had to order a converter with a special "8 bolt crank flange front cover" for everything to come out right.

[Moparal]

I just measured a 68 440 stock crank hub for you a minute ago. Useing a regular tape, I measured 5/8th of an inch in depth from the top flange into the bottom. Not including the pilot hole. Just the area shown for where the converter hub slides into

[hemitodd]

hey guys

thanks for all the effort

one day off and lots of family stuff to do so i only had 5 minutes in the shop.

i measured the crank from a '67 440 and it was 0.652" deep and measured my engine it was 0.640".

heres a pic of my torque converter(you can see the line where the other flexplate was running into it) the face does look different from my brother-in-law torque converter from a 440(blue).

[hemitodd]

hey guys

 just had to add this, just got back from the fall fair near where i live now. moved from the city to here (population 800)
i used to go out to cruise nights in the city where i lived and  usually 200-300 cars would show up and there would be only a dozen mopars out of that.

they had a little car show at the fair today and there where only 14 cars and there where 6 cudas , 1 challenger, 2 chargers  and just as i was leaving a 69 and 70 road runner pulled in.

oh did i mention the 67 charger and red 70 cuda in the one pic where hemi cars.

any way thanks again for all the advice and any more input on my dilema

[hemitodd]

Yesterday i had a chance to put the converter up to the back of the crank, it bottoms out just as the pads touch the flexplate  .  should i put shims between the pads and the plates so the hub isnt touching the bottom of the crankhole?

i have my brother-in-laws transmission(which he doesnt have a problem with) and im going to bolt it up with my converter and try it out so i can atleast eliminate it.

ntstlgl1970

sorry i skipped over your post by accident, its problem ive always had.  it seems rpm related (2500 to 3500) . i measured crank endplay with a dial indicator by gently prying against the back of the crak flange. its less than 0.010

quagmire

there is no bushing in the hub and new flexplate fits the face of the converter much better

[tactransman]

Usually the problem is the 8 bolt crank flange. The bolt pattern is a little bit bigger due to the extra 2 crank bolts and that usually makes the crank bolts touch the converter front cover in a way that does not let the converter come back out of the pump the right distance when you tighten the converter bolts. I don't see any touch marks on your front cover, but there might need to be a dimension difference some where else too. I don't know if this is your problem,I am just letting you know what I have experienced to see if it can help you. 

P.S. washers on the converter pad is NOT the answer.

[hemitodd]

tactransman

thanks the advice i really appreciate it when bought the cuda i didnt know a thing about cars, and the people i hang out with dont know much about cars so having a guy like you and the others to help me out is priceless

i did check the crank bolts too and no they arent touching.

[74 340 4speed]

If the hub on the converter is just slighty rubbing on the inside of the crank, can the hub be machined down .01 or .02" of an inch to regain this clearance?  If it is machined flat it shouldn't effect the balance of the converter, should it?  I know a company that makes a bellhousing alignment tool that may help you with your problem.  Chryco stated that the dowel pins could possibly not be lined up correctly.  http://www.browellbellhousing.com/pages/accessories-page.html   I have used one of their tools and it is very nice and simple to use.  The only way I know of for you to be able to verify that the pins are properly aligned would be to get a 4 speed bellhousing though.

[hemitodd]

Thanks for the info 340

i did swap in another transmission with the same torque converter and took it for a run yesterday and the funny vibration is still there, so i think i can eliminate the tranny.

im going to pull it out and see what else i can check.

i do have old transmission i might gut then i can bolt the case up and attach a dial indicator the crank. ( i read somewhere where you can do that to find out if you need offset dowel pins)

i'll keep you posted