Nailhead Overdrive

[Guest]

I have a 1939 Buick with a 401 Nailhead and automatic. The rear gear ratio is quite low for highway driving. I would like to chnge the transmission to an Overdrive unit. Does anyone know what will work?

[Guest]

There are no trannys other than the ST300,ST400 and Dynaflow that will bolt to your motor. And you can't even mix dynaflow and St300/400 motors. I suggest getting taller gears for the rear or changing the rear all together. Your 401 has so much torque that you don't need low gears to have good pickup from a stop. <P>------------------<BR>buickfam@aol.com<BR>Life long Buick Fan.<BR>1965 Skylark H/T<BR>1965 Gran Sport Convertible<BR>1948 Chevy Pickup with 401 Buick.<BR>"Fan of anything that moves human beings"

[brad54]

I would think TransDapt or some other company makes a transmission adapter that would go from the nailhead to a standard BOP or Chevy bellhousing.<BR>If there isn't, and you really feal adventurous, I'm sure a local machine shop (one with a friendly owner) could make you the adapter plate, crank-to-flex plate spacer, and figure out the provision for the starter motor. It shouldn't be that difficult for a capable shop.<BR>Cost is another matter...<BR>Good luck!

[Guest]

Darrell, put a Gear Vendors over/under drive unit on your current transmission and enjoy that Nailhead low RPM torque as you sail down the highway at high speed.

[Guest]

Brad, no one makes one. there has been rumors about a guy that is "going to" make one, only a dream so far. The problem is the nailhead has a block that hangs off the rear. The torque converter sits into the back of the block about three inches. <BR>So to make an adapter you would have to include an extension to crank to reach the tranny that would be three inches or so farther away. <BR>The other way would be to cut the front of a 700R4 off and weld on a nailhead bellhousing area. I have seen this done. But again I have to ask, why? The nailhead has so much torque you can run 3.00 gears and still drag a house off the foundation. <BR>I have 3.36 gears in my Gran Sport, and unless I am at the drags, I wish I had 3.08s. My truck has 3.08's and I still can beat just about anything across an intersection. <BR>I say to heck with all these overdrive flibity flu trannies, run a ST400 and get the job done.<P>------------------<BR>buickfam@aol.com<BR>Life long Buick Fan.<BR>1965 Skylark H/T<BR>1965 Gran Sport Convertible<BR>1948 Chevy Pickup with 401 Buick.<BR>"Fan of anything that moves human beings"

[brad54]

Cool--thanks for the info. <BR>Because I really like excercises in futility, I'm trying to figure out a way that I can run a 3 speed manual overdrive trans behind the 322 I'm going to put in my '54 Buick.<BR>One of the Chevy units after '58 will work best becaue it should have a cross member mount cast into the trans case (unlike 55-57 Chevy units with the bellhousing motor mount), and with the corresponding steering column from the donor car, I'll be able to shift.<BR>The unput shaft on the trans is what's blocking my progress: stock Buick input shaft is already longer than later Chevy input, so I can't have an adapter made.<BR>I've got another post (no replies) wondering if the the bellhousing used by '59 GM trucks will mate the GM trans to the 322 Buick Nail head. But I think it's one of those things I'm going to have to spend money to find out.<BR>I've got a donor rear for the car that I'll pirate the spring/panhard perches from, as well as the wishbone mounts and backing plates to put on an open rear.<BR>If I can't figure out the bellhousing situation, I'm going to have a local machine shop lengthen the input shaft and re-heat treat it. <BR>-Brad

[Dave@Moon]

Here's a silly question. Hasn't somebody somewhere made a 2-speed rear end for the Buick drivetrain?

[Guest]

Since we are talking trannys, would any one recomend rebuilding a dynaflow for behind a 322 or try to go with something else? I was told by a few guys that this tranny was nicknamed dynaslow.

[Guest]

CarCraft or Hot rod did a 200r4 install in a 67 buick a few months back check out the article.<P>------------------<BR>Gatomon

[The Old Guy]

John53,the dynaflow by 1959 was a very dependable unit and when they started using the variable pitch converter they became much quicker. Thay were not as quick as the 400 TH ,but for towing they were great ,as the power was applied very smoothly.blackcat you are right about the article ,but the67 was not a nail head engine, so it was practically a bolt in operation. they did make stick shift nail heads ,so you should be able to find a bell housing and use that as a starting point.

[Guest]

I do have a 1959 364/401 manual flywheel if anyone needs it. <P>------------------<BR>buickfam@aol.com<BR>Life long Buick Fan.<BR>1965 Skylark H/T<BR>1965 Gran Sport Convertible<BR>1948 Chevy Pickup with 401 Buick.<BR>"Fan of anything that moves human beings"

[Guest]

I just talked to a guy who used the 364<BR>stick shift bell housing and an ofenhauser<BR>adapter and put a gm standard trani behind <BR>it. Don't have all the details right here<BR>but I can get them if any one is interested.

[brad54]

Does anyone know of an easy way to put a late-model 4-speed behind a 322? I don't car about shifter or clutch linkage--it's the bellhousing/input shaft that's causing the problem.<BR>-Brad

[Guest]

I have an adapter to install a 53 to 59 Ford manual tranny to a 322, maybe it could be modified?<P>------------------<BR>buickfam@aol.com<BR>Life long Buick Fan.<BR>1965 Skylark H/T<BR>1965 Gran Sport Convertible<BR>1948 Chevy Pickup with 401 Buick.<BR>"Fan of anything that moves human beings"

[Guest]

Martinsr, will that adapter fit a 364<BR>bell housing? I have a 57 ford 3 speed<BR>trani.<p>[This message has been edited by flatblack (edited 02-15-2001).]

[Guest]

No, but check out htis eBay auction and then click on "view sellers other auctions" and you will see an adapter and solid lifters for your motor. <P>------------------<BR>buickfam@aol.com<BR>Life long Buick Fan.<BR>1965 Skylark H/T<BR>1965 Gran Sport Convertible<BR>1948 Chevy Pickup with 401 Buick.<BR>"Fan of anything that moves human beings"

[Guest]

Thanks Martinsr but the adapter plate<BR>fits caddy trannys. I had actually already<BR>seen it, thats why I wanted to know if<BR>your adapter would fit that bell housing.<BR>Well I have more than 1 ford trani so if <BR>someone wants to use your adapter for the <BR>322 I got a trani for ya<P>I'm curious though, what clutch is gonna<BR>fit the ford shaft and bolt on a buick<BR>flywheel?<p>[This message has been edited by flatblack (edited 02-16-2001).]

[brad54]

The fix for the clutch/flywheel will probably be to get a stock pressure plate and bolt it to the flywheel, and then order a clutch disc of the correct diameter and specify the spline count for the Ford tranny. Someone like Fort Wayne Clutch should be able to mix-n-match like that.<BR>-Brad

[Guest]

there's another post about<BR>what happens with the drive<BR>shaft being the torque tube,.<BR>doesnt look like a ford trani <BR>is the same length as a dynaflow<BR>so would you have to have a drive <BR>shaft made?

[brad54]

My understanding is that when someone does these swaps, it's usually to put a cool nailhead engine in something less cool, like say a '32 Ford hot rod. (Did I just say '32 Fords aren't cool?!) At that point, there's a conversion to an open drive shaft system, or the hardcore hot rod guys would stick with the Ford's torque tube under their roadster.<BR>A lot of guys who hot rod their Buicks will also get rid of the closed driveshaft/torque tube and convert to an open driveshaft. On a '57-up Buick, that's not as hard because they can just replace the Buick trans with a later 4-speed, or auto trans. Then they get the rear end of their choice and hang it out back. Us 322 guys are stuck, because of the bellhousing differences. (though bolting on a Pontiac 3-spd manual tailshaft will convert a Buick 3-spd manual to an open driveshaft)<BR>For the rear end on my '54 (when I do it), I've got a spare housing and I'm going to have all the spring mounts, etc. welded to a Mopar 8 3/4 rearend fitted with GM end flanges (so I can keep the stock drum backing plates and lever shocks). For the "wishbones" that connect to the torque tube, I'm going to keep them running forward off the rear end housing, but I'll make a driveshaft loop/crossmember that they will attach to in the middle of the car.

[Jyrki]

May I throw in a silly question: does the 322 have the same trans bolt pattern as the straight-8? I have the same problem - can't swap the axle because the stock trans won't accept an open driveshaft. I want to keep the 320 mill, so I'm stuck with 4:1 gears. <BR>So what is this talk about a Pontiac box - I'm all ears!

[The Old Guy]

You aren't stuck with the 4.1 gears! you can use a center section from a 55 and it will bolt in and give you a 3.4-3.6 and all you have to do is use your torque tube and drive shaft. 40 through 55 are interchangable

[brad54]

What year S8? My classic interchange has a ton of notes about different applications. I only looked in the '54-66 set of books (didn't think to look in the earlier set before I started typing here) and the notes indicate interchanges with trans parts to '53, but it may go lower in the other books.<BR>The notes are a nother mish-mash of "main shaft and extension from this year, our wreckers say that year fits, etc...."<BR>Let me know what year your car is.<BR>Hey OldGuy, I didn't realize that the diff on my '54 would interchange all the way back to 40 (my interchange book said '54-56), but here's a problem I've had that you might be able to help with: how do I seperate the driveshaft from the pinion gear snout? The factory manuals say to use a special puller at the dealerships, but I don't happen to have one of those laying around.<BR>My solution is to take the whole thing to a drive shaft shop and have them cut the bung/pinion off the driveshaft with thei lathe, and then shorten the 'shaft four inches and rebalance to fit my shorter Special. I've got 3.90 gears, and look on those 3.40's with envy.<BR>I always feel like I'm taking the longest possible path between two points, but the path I'm trying to travel hasn't been tread upon in decades.<BR>-Brad

[Guest]

brad, I've got a '57 century with a 364.<BR>you say it's easy to switch to a later <BR>tranny but everyone I've talked to on here<BR>says nothin' fits but the dynaflow. What is <BR>the book you're lookin' in? and let me know<BR>if it shows some possible swaps, my stock<BR>dynaflow is hurtin and they seem to be real<BR>expensive to fix if you can even find someone nearby who knows how. thanks

[Jyrki]

I have a 46 Roadie. Looking back into the earlier discussion initiated by me - "rearend gears" 02-03-2001, geearsets at least thru 1953 would be a bolt-on, but people are uncertain about the 54-56 years. 57 is a necked-down torque-tube, and the last one of the kind. The problem is, there's not too many 40's-50's buicks in Finland. I'm pretty sure that someday someone will fabricate an adapter to mate a late model trans to a S-8. I would like to keep my buick as original as possible, yet streetable (or better yet, highwayable)

[The Old Guy]

The rear end design was changed in 1956. the gears from 1940 through 55 bolted on the carrier, and the later ones are riveted. The complete center section will interchange , but you have to use your drive shaft and torque tube. The drive shaft removal can be tough. I knocked out the pin and made a wedge that fit between the splined coupler and the housing and beat it off. The biggest problem i found was making sure that the drive shaft ran true . there is a section in the manual that tell how to do it

[brad54]

Old guy: My '54 shop Manual says the ring gear is riveted on the differential, and to change it you have to order the bolts (I don't remember reading if the replacement gear needs to be tapped or not).<BR>I can get the bolts from Drive Train Services. Anybody have a stash of highway gears? I've also heard that banging the driveshaft off can snap the pinion gear's snout off."Hmmm, door with the lions, or door with the tigers?"<BR>FlatBlack: The reference book I've got is a 7 book set (it's actually 4 sub-sets, but I've got them all) from ADP Hollander. Hollander is the company that makes the books that junkyards use to tell you a starter from a Later Bronco will fit a '69 Mustang. They've got a classic interchange set of books, and I use it a lot. The sets range between $39.99 and a tick over $100, but like I said, I've used them a lot. If you're interested, you can call (800) 825-0644, and I think their website is <A HREF="http://www.adphollander.com," TARGET=_blank>www.adphollander.com,</A> but I'm not positive.<BR>The books say the flywheel cover (bellhousing) will interchange from '57-61, w/o Dynaflow. I'm going to assume that means a stick shift bellhousing is the same for all those years, which means the bellhousing pattern on the back of the 364 engine block is the same as the later model engines. To keep the closed driveshaft on your car, you'll probably have to keep the stock trans. I you go with an open system, you might have a few more options.<BR>If anyone has any corrections or clarifications on the 364 bellhousing pattern, please let me know, because I'm just speculating from what I read! I don't have one in my garage to look at.<BR>Thanks,<BR>-Brad

[Guest]

thanks brad I'm gonna look for those books.<BR>I'm trying to start another topic about the<BR>options for the 364 since this started out <BR>for 401 and 322 questions about the rear end.<p>[This message has been edited by flatblack (edited 02-22-2001).]