OK, so I'm finishing up my '27 model T and its got a 1964 Buick 401 nailhead with a 1965 Buick SP 400 automatic transmission. It runs fine, but I'm noticing a weird vibration just above idle. I had to buy an adapter for the crankshaft to mate the variable pitch torque converter to it, and I removed the little "flange" on the back of the crank to bolt the 1965 flex plate to it. I'm thinking that the flexplate needs to be "timed" to the crank for balancing, but is there a mark that I can line up since these two items weren't designed to bolt together? I'm assuming that I will be forced to remove and reposition the flexplate several times until I get it right, but I was hoping that someone on here would know a shortcut. Thanks.
Pard, if I understand you correctly, you ground the flange off of the back of the crank on that engine????? If so you destroyed the crank.... because the flange is what keeps the flex plate centered... you should have made the flex plate work with the crank, or changed the crank to one that would work with the flex plate... if the flange is cut off of the crank there is nothing to keep the rotating mass of the torque converter/flex plate centered and they will get off center enough to viberate with nothing but the bolts holding them .... the converter and the flex plate are each balanced as a unit and so thier balance should not be a problem...
Cool car!:TU: The flex plate needs to be indexed correctly to maintain balance. There are 6 bolt holes, and one index hole (in crank and flexplate). Line up the index hole, and then install the bolts. If you grind off the lip to use a newer trans, you will need an adapter bushing to keep the flex plate centered. You can buy one of these: http://cgi.ebay.com/ebaymotors/Buic...yZ140685QQssPageNameZWDVWQQrdZ1QQcmdZViewItem or make your own.
When I got my adapter from somewhere I won't name I was disappointed because it didn't fit correctly and seemed kinda "cheesy". After looking at the link listed above I definitely know what I should have gotten instead. I never saw those adapters in all my searches on ebay, so thanks for the link. Will a '64 crank have the index hole to line up the '65 flex plate? I didn't notice when I put it together the first time, but since I've got to take it apart to install the new adapter I figured I'd better get it timed correctly this time. Thanks again.
If This Is Truely A 64 401 I Dont Think You Should Have Needed Any Adapters. The Dynaflow Trans Was In 63. Let Me Know For Sure Because Im Going To Be Bolting A 64 401 To A 65 Sp 400 Myself
I ran the numbers on the block and came up with 1964. I don't know them off the top of my head, but when I get home I'll post them and you double check me. I definitely needed an adapter for mine because the crank has a HUGE hole in it for the dynaflow converter snout, and the variable pitch converter has a normal, little snout. Maybe Buick ran some dynaflows early in '64?
crank might have been swapped out with an earlier crank at some time did you have the engine machined? I had a buddy who brought his BBC427 to a machine shop and they tried to give him a 454 block back:rant:
