What is the best Buick Nailhead Motor?

Looking for a Buick nail head motor for a project and just want to know if anyone has knowledge of what year and size to get and what to stay away from and why. I have several in my sites right now just not too familiar with them.
Thanks Red

 

the answer may depend a bit on what you desire to put this engine in. Do you wish to purchase speed parts for it? Will it be raced or just used in a daily driver? What type of transmission do you desire? The answers to these questions will allow for a better answer. I think they are all pretty darn good, but some will fit your particular application better than others. It may also depend on your budget.

from a technical standpoint, I would defer to Zman to fill you in on the "best" nailhead.

 

63-65 425 nailhead.imo,65 or 66 because uses the same bellhousing as the sister div.bop.

 

They are all nice engines but personally I'd go with a 64/66 401/425 that had a turbo 400 behind it from the get go. Open drive from the start and a trans that is not a bank breaker to work on.
Adapters for the earlier engines can be had here http://www.transmissionadapters.com/Nailhead_install.htm But the added cost of the adapter may negate the savings on the engine.
I've always been a big fan of the nailheads ever since I ran the wheels off my 55 Special 4 door hardtop in the mid 60's. If you go for an earlier engine get one out of a Century, Super or Roadmaster with the 4 barrel on it from the factory.

And as hotrodstude said the 65/66 425 will take a Pontiac or Olds trans or later Buick trans without an adapter. That makes a big difference in trans choices.

 

401/425 seems to be the more versatile options. Buick went to open driveline in '60 I believe, so anything after that would be alright, but as it's been mentioned, Buick kept the Dynaflow through '63.

The Dynaflow is a pretty terrible transmission. It's notorious for leaking, I've heard stories of guys rebuilding them and just a few weeks later they began to leak again. I have a 364 Nailhead in my '57 Buick, and the shop manual has a huge section on troubleshooting trans. leaks, on a brand new car. Other than leaking, the transmission is basically a one-speed slushbox. If you could get one with an ST/SP 400, I'd definitely go that route.

 

I can only offer an opinon, not really any technical insight.

Years ago I fell in love with full fender Duece sedan that had a straight axle ... and I mean a straight axle !!! It had a dual quad 425 from Riviera and a 4 speed. The thing I remember most were the factory aluminum rocker covers with "Buick" cast into them. I know that the engine was not stock but not sure what all was done to it, I was 12 at the time (46 now) but I do remeber the terms bored and stroked. The neighbor that owned it took me for a ride, I was hooked for life !!! I have built that car in my head a thousand times ...

 

I gotta agree with the 401 (445 ft.lbs. torque) and the 425 (465 ft. lbs.) idea, although all of them were good, reliable engines (and I like the "looks"). You don't say what your priorities are, but if it's torque you're after, nothing beats a 455 (501 ft.lbs.).

 

NOT.
B.O.P is 67 and later, not Nailheads.

 

Any Nailhead is good I like the 401-425's early 264-322's don't have balancers

 

Is there an external size difference between them? I am thinking about putting a 401 or 425 in my Model A. I want to be able to run a full hood without side bump outs.

Mike

 

How difficult is it to find a 4 barrel intake for a 364?

 

BOP pattern actually originated in 64, but not for the nailheads. Only newer Buick and Oldsmobile in 64. 65 up Olds and Pontiacs are BOP. SBB's from 64 up. BBB's 67 up.


I vote for 64-66 401 or 425's since they are ready for SP400 transmission.

 

I vote 401 & 425.

 

Bigger is better..................I have a few different Nailheads and none of them are "bad".......

Check this out................... http://www.jalopyjournal.com/forum/showthread.php?t=330306&highlight=nailhead+picture

 

Great info thanks, Lookin to do a A-Coupe with a nailhead can't beat that combo.

 

Every time I look at that post I get a weird tingly feeling!
The 63-65 401/425. is the best engine IMO. The 364 has a few good points (a lot of parts from the 401 and 425 change over.) The ultimate would be a 65 425 dual quad, with a 4 speed!!!

 

401/425 had factory option dual quads also, and is easier to find 6 packs for. Trans-dapt is the place for any adapters you might need. A 401/425 with modern 5 spd would be WAAAAYY cool, and still get you into the 20-24 mpg range. Few motors look cooler than a dressed nailhead!!

 

Here is exactly what you need, How can you be "trad" without a 50's mill? What's cooler than trips on a 58 nailhead?

http://www.jalopyjournal.com/forum/showthread.php?t=499049&highlight=nailhead

 

Very good points, 401's and 425's are hard to beat, 322's are so right in an early roadster or coupe if you want it to be period. Don't count out the 364 either. But they're all good but for parts availability right now I'd say 64-66 401/425.

No Nailhead is BOP. Hell no other engine shares of the Nailhead bellhousing patterns.

the got taller and wider as they got bigger. but not much. there are a few nailhead powered A's on here if you look, Rolf's comes to mind first.

though it's easy to put it on the 364 and early 401

lol, I'd love to have 20-24 out of mine. But really don't see it happening any way.

 

Hi I was wondering how good is a 401 nailhead with a 2 speed superglide? And how much would it be worth with all number matching and would it be a good trade for a 1987 Yamaha warrior?

 

dynaflows were smooth, but guzzled gas!

 

Maybe it's just my drag racing background, but to me the biggest cubes you can get in a given weight package is the way to go. My friend Ray has a 425 with a 400 turbo behind it in his '32. Hauls ass!

 

This is the 2nd year, + 10,000 miles, since completion of my avatar Model A with it's 54 Roadmaster 322, can't say enough about this engine, simply love it.

 

How good are 401 nailheads with 2 speed superglide?

 

Nailheads are like lady parts, they are all good, just some better than others. What the hell is a 2 speed superglide? It sure never came from a Buick!

 

I'm running a 401/425 with a T400SP in my full fendered 28 A roadster pick up. I run a full stock hood. I have a big block rad. It runs hot in 90 degree weather, but once on the highway it drops to 150 degrees.
I run tall gears and its a hoot to drive.

 

As far as looks I like the ones with spark plug covers.

 

Agree with the others, the 64-66 401 and 425 with the ST400 or SP400 trans is a great combo. There were a few manual trans big Nailheads, used in the Skylark (I think??) but those are rare as it gets. All of the bigger Buicks had the 400 auto trans. Also agree the bellhousing bolt pattern is *not* the same as BOP, it is unique to Nailhead. Small Nailhead 264/322 is also not the same as the bigger Nailhead 364/401/425. There are three different deck heights, and therefore three different intake manifold widths: shortest is 264 and 322, then middle is 364, and tallest is 401/425.

Even a 2 barrel 401 is pretty strong, but aftermarket intakes for the 401/425 are pretty easy to get. The Nailhead bellhousing pattern ST400 or Sp400 trans are basically the same as the other turbo400 trans, although 64 ST400 has a one-year only valve body that is unique. Not bad unique, just different. 364 only had the dynaslow trans and torque tube drive. A big Nailhead 400 trans can be adapted to the 364 with some minor work, not a direct bolt-on due to crank pilot differences between dynaslow and 400 converters.

As long as I am on my nailhead soapbox, the Buick/Olds 215 and 300 engines are sometimes called baby nailheads. They are not, they only have similarity of the valve covers being straight up like Nailheads. Real Nailheads have the distributor in the rear. The 215/300 have it up front.

 

Sorry I ment a powerglide lol and how good are powerglides

 

I have a 322 with 2-2's, early buick manual trans, and I have a 401 with 3-2's with a switch pitch 400.

If you're not after era correct go with the 401/425 and take advantage of parts availability, and 75-100 extra cubes for the same weight, and probably easier to adapt to other transmissions.

The 322's are great little motors, lots of torque, run cool, like extra carburetion, find one complete with fuel pump, water pump, as some of that stuff is getting hard to come across, and having a matching crank/flywheel or flexplate is a plus to insure the balance (unless you plan on tearing down and re-building re-balancing). A 56 might be the best year of all the 322's, but any will work if you plan on re-building it. You can open up the valves to 364 specs. don't do hardened seats (you may hit water), rebuild kits are available (Falcon). I have a thread on some valve spring issues I had, but resolved with some Toyota springs.