GUYS the question came up about putting a 200r4 trans in a65gs the gs has the 401 in it/////NOW i know for sure this is a easy swap if your eng is a 300 or 350 /455 but im not sure about the 401 but i remember reading on here that some or all of the nailheads had a different bolt pattern ////// can someone set me straight please pete
401 with a 200r4 no can do without an adapter of some sort. nailheads have a completely different bell housing bolt pattern and shape. sort of like the early hemi's or fat head fords (err flat that is) part of the bell housing is part of the block Jon
The adapter is available but it is not cheap. I have the company listed on our site in the Helpful Tips article.
thanks george /////so that means that the trans in a 65 gs is different from a 65 skylark///right ???then what trans is it and what other models had it ???cause it might be cheaper to go that way if we decidto use a 401 thanks pete
You should have a SP400 in your car. You can use any later model trans from a Buick, Olds, Pontiac provided you get the trans adapter plate. The plate was something like $200-250. This will allow you to run a TH400, TH350, etc. The bellhousing for a nailhead is hemi-spherical shaped and is specific to the Buick nailhead 401/425.
Forgot to mention, you can use a trans from any 65-66 Buick with the 401-425. I believe all, full size, will use the SP400. The regular Skylark used a 300 engine and a different trans, SP300.
65 wildcat GEORGE one more question will an eng and trans out of a 64/65 wildcat swap in to a 65 sky lark the lark now has the 300w/300sp you already told me we cant use the 300 trans////so if we use the one that is out of the wildcat what are we in for ???? thanks pete
The 401/425 out of a 64/6 big car should fit but you will need all the 65/6 Skylark GS parts to make it fit. Major parts are a rear sump oil pan, exhaust manifolds, and complete motor mounts. Cross member will need moved for the T400. What I do not know is the 300 trans out of a 65/6 Skylark with a 300 motor the same as he one they used in the 65/6 Skylark GS? Thanks Bill.
The trans out of a 64 will not be a switch pitch trans, 65 and 66 will be. The 64 is still a solid piece but just so you do know there is a difference. Confused yet :laugh: Prior to 64 they were Dynaflows which is another small can of worms to deal with.
