Just after I spent $3k for a completely redone Dynaflow I started thinking about hp. Is there anything I can do to add hp to my stock 401 & still keep the stock 2 speed? Most hi perf parts are for 400s & 455s, as I have not seen much for the nh. Used to have a Poston catalog but I believe Poston out of Alabama is no longer in biz. How much, if any, parts are available?
GM Man63 check out the "sticky" thread at the top of Da Nailhead section, it may give you the leads you are looking for. http://www.v8buick.com/showthread.php?t=2460 Parts range from after market manifolds, blowers, wide range of camshafts, forged pistons, mini starters, and Toms Roller rockers. There is a truck load of info here, you may just have to do a few searches. Some of the Specialist Nailhead guys here can also increase cylinder head and manifold performance by porting etc to improve flow rates etc. Ross
Hate to be the one to tell you Gmman but that 3K on a dynaflow might have been put to better use finding a switch pitch tranny. The dyna robs a lot of HP and just does not have the "umph" to feel like a high performance piece of equipment. A switch pitch SP400 (found in 65-66 Nails) with a converter out of a 300 (smaller engined cars) sent to Jim W (board owner/creator) will optimize the performance in your nailhead. When I switched the stock 64' ST400 for a 65' SP400, I shaved a full second off my 1/4 mile times. If it were a Dynaflow it would have been an even better improvement. Just some food for thought. As for HP parts they are out there but a Nailhead ain't no small block Chebby. You have to search a little harder for parts but they can be had. A lot of the leg work has already been done for you just search the board it is all there for ya.:TU:
Go to the wrenchin secrets section and ck. out my list of cheap tricks there ..... I have done all those and they really work... Yaccy is right about the transmissions....
I love the Dynaflow, and it's a good, strong gearbox, but absorbs a lot more hp then a THM 400. Not much point in putting a lot of $$ into the engine, then losing a pile of hp in the transmission. There is a difference in crankshafts between Dynaflow and THM engines. Doc can tell you what you have to do to swap the Dynaflow for a THM 400. With a little patience and some detective work, you can find lots of stuff for Nailheads. Spend some time here on V8Buick.com, there is a lot of knowledge concerning Nailheads on this board. Many of your questions will probably already have been answered; there are lots of good folks who will be glad to help you. Do your homework first - you will avoid some expensive mistakes. If this engine and transmission are going into a 'rod; you might want to consider something like a 700R4 tranny. It absorbs even less hp then the THM 400 and gives you an overdrive. You will need a transmission adapter (available) though.
Swapping from a Dynaflow to a '66 ST400 is hands down the best thing I've done to my car. It's a fairly easy swap too. You'd need a crank bushing adapter, the ST400 flexplate, and later ST400 syle starter, as well as the correct trans crossmember, and a shorter driveshaft. I'd hate to say you wasted your money on the Dynaflow, but it definitely is not the best choice for a performance application. In terms of other easy items you can do, look up the "doc dual-plane" mod. Also, re-curving the distributor, and a nice free flowing exhaust (either porting your factory manifolds, and a nice dual system, or a set of headers, and a nice dual system) would do wonders. If you want to get more in depth, you could also start looking at a cam swap, and getting the heads ported. Not sure what your looking for in terms of actual HP numbers, but I think that I'm realistically pushing the factory rated 325hp with my current setup. Once I finally get my posi in, I plan on weighing the car and taking it to the track. I'd be thrilled to just dip into the 14's.
I don't know what your financial situation is, but the prevailing thought is that Nailheads love carburetion. I have not personally tried it, but members rave about the "Doc dual-plane" intake manifold mod. There is a rumor that Edelbrock may be coming out with an aluminum single-4bbl intake manifold in a year or so. If they do, it will flow well. The Edelbrock dual-quad intake manifold flows well, as does the Eelco. The Offenhauser does not. The factory cast-iron dual quad setup works great, but is quite pricey - particularly if you want the factory air cleaner housing. In 1966, Buick used the Quadrajet on the 425s - not sure about the 401s. If you are a Quadrajet lover, that's the intake manifold you want. As it is a one-year-only part; they are relatively rare and a bit on the expensive side. There's a lot on cams here. Search "cams" or "camshafts" and you will find a lot of info. Have fun!
that is exactly why I stick with the switch pitch 400,,,, so far I have managed to weasel into several for less than $600......:laugh: :Brow:
I got a very good deal on my trans, flexplate, and starter, but I'm the ST400 swap for less than $750.
can some one tell about the dynaflow,is that the one with no gears with a really high top end.my brother had a 56 buick i remember going 110 mph and the engine felt like it was turning at a very low rpm,if thats the case you will have a lot of top end with your new dynaflow.
Yes, a Dynaflow placed in Drive has no gears shifting. At least not that you can tell as the driver or passenger. The '63 version (last version) actually does have a planetary gear set inside the torque converter that gives you some gear reduction when starting out, and then automatically changes to a straight-through torque converter as road speed goes up. The action of the planetary gear is all tied to the difference between the input RPM (engine RPM) and the output shaft RPM on the torque converter (road speed), and it's all done with pure fluid dynamics inside the torque converter. There are no valves controlling it. (Not to be confused with the "Switch Pitch" torque converter in this Dynaflow, which is controlled by a valve.) It is a very smooth transition from starting out (using planetary gear in TC to not using it) and you don't notice it unless you know what to watch for. At highway speed, the Dynaflow it is the same as a regular 3-speed transmission in high gear, so top speed potential is the same as any other car (without an overdrive). Thus your 110 mph in your '56 Buick. The biggest difference is that Dynaflow-equipped cars usually have a lower gear in their rear end, compared to a non-Dynaflow car, to help with acceleration. So your theoretical top speed it slightly lower due to that, at the same engine RPM. You can manually move the selector on a Dynaflow down to the Low position and that gives you a low gear for pulling up a steep ramp, etc., but that low gear is not used in normal driving. You leave it in Drive all the time and the transmission does not go into that low gear on its own. If you want to race, you can manually start out in Low, hit the gas, wind the engine up, and then at about 40 MPH push the selector into the Drive position under full power. If you do, you will eventually blow the seals inside the tranny. The Dynaflow was not designed to run that way (but we have all done it over the years!). A Dynaflow will not be as quick off the line as a "normal" 3-speed auto tranny that actually shifts through all the gears. Even with the fancy "twin turbine" torque converter, you don't have the gearing advantage for acceleration like you do with a normal transmission that shifts. If you are drag racing, you don't want a Dynaflow. The Dynaflow's big claim to fame is its smoothness. It was something that Buick was known for all through the 50s and into the 60s. Everyone who rides in my '63 Riv comments on that. You have smooth application of power at any speed. Since I don't drag race this car, I actually prefer it to the later model Rivs that shift gears. YMMV.
The Dynaflow is a nice transmission; just not great for acceleration. Essentially, when in "Drive," The torque converter is the transmission. The planetary gearset inside the transmission is just for "low" and "reverse" gears. Basically, the transmission housing contains a planetary gearset, a front oil pump, and a rear oil pump. Yes, you can push start a Dynaflow equipped Buick. Top end is great - it just takes a while to get there. If you are going to run Bonneville, I'd stick with the Dynaflow. If you enjoy your car in 1/4 mile increments, the Dynaflow would not be my choice of a transmission. Obviously, I was writing this at the same time as the above post was also being written!
Whoa! My head is spinning with all your guys' knowledge! I actually DID consider a new transmission (with adapter kit), but wanted to keep the 63 as close to original looking as possible. I have owned hi perf, customs, & stock automobiles, but I've been watching a lot of "My Classic Car" with Dennis Gage and getting kind of antsy. I LOVE my car as is, but was considering adding a little more oomph. I wouldn't drag it ever (and I have never beat on it the 13 years I've owned it) but might like a little more...pizzazz if you will. Thank you all for all your knowledge & advice so far! Glenn:beer
NICE, thanks guys for the information. you should be all set with a few mods to your engine to get that little more power.on my skylark gs just changing to a bigger carb and air cleaner was 2.5 or 3 tenths.
i dont think you would change anything with the stock look by going to a better trans i realize its to late now just saying
If you are trying to keep your '63 Buick stock-appearing, I would go with the "Doc approved" '091 cam and leave it at that. The "091" cam is part # 1368091. They are rare.
