Ive been reading a lot of nailhead info trying to get more power out of my 264. I finally got to Docs intake mod and was interested but I dont think anyone was doing it on the Baby Nailhead. I have the 264 with Dynaflow in my 55 Special, it really has no power off the line. I bought a 4 barrel and WCFB to swap over. I remember reading a while back that the 4 holes in the intake help increase low end torque but cutting the manifold open like you guys do sacrifice some of the low end torque and trade it for better breathing in the mid and high RPM range. Is that true for the nailhead? Should I just leave the manifold alone and bolt it on? Also what are exhaust manifold extensions?
Based on my experience with the 264, the 322 4-bbl manifold and dual exhausts will make about as much extra horsepower as anything else that you can do. The Dynaflow 264 already is the high-compression version of that engine. Sadly, although the Dynaflow is smooth and reliable, it is not the best choice for acceleration - nor was it intended to be. All of my 264 experience is with manual shifters. The stick version of the 264 had lower compression, but we would install the thin steel headgaskets, the 322 4-bbl manifold, and the '56 Buick dual exhaust manifolds (which are really cast iron headers). My 264s regularly took down 324 Oldsmobiles, 292 and 312 Fords, (once in a while I would lose to a good 312) mid 50's Pontiacs, and the 352 and juicy lifter 390 Fords. In fairness, I once saw a 225 Plymouth slant six station wagon take down a 352 Ford. The 318 Mopars weren't a problem, but once you got to the "B" engines, I was very choosy about who I raced. Finding a complete stick setup for a '55 special would be a challenge today. I have a flywheel and bellhousing, and I think Tom Telesco has a transmission, but where you would get the shift and clutch linkage would be a matter of persistence and luck. And you need the Century or '56 manual transmission. You will break the small '54 and '55 Special gearbox. I have seven of them to my credit. ou:
I thought you cant get Duals on a 55 because there is no path on the drivers side. Did you bend the pipe and go across to the passenger side and then have them run parallel to the back?
In general, the purpose of cutting the holes out is to increase plenum volume. Put simply, there is more fuel/air mixture available in the plenum (the area directly beneath the carb on the manifold) with the material removed. If an engine isn't large enough cubic inches-wise or efficient enough to utilize the available extra fuel/air mixture, it will take it a while to get revved up to create the proper volumetric efficiency to use it. A small, inefficient, or low rpm engine benefits from small plenum volume, in general. But, a four hole intake is probably much too far restricted for all but the most low performance and low efficiency engine. Long story short: I'd remove them myself. It'll probably cause you a very slight dip in power just off idle, but if you keep a properly size carb on it, you'll never notice the lost bottom end, and the mid and top will be much better.
Well,,,, this is my thoughts :laugh:,,,, be double sure that you leave the center divider in the intake,,, that is the one that runs down the center of the car lengthwise,,, it you cut that out ,, it will kill the torque.... and you need all the torque that you can get... now,,,, dont block the heat risers in the intake,,, keep them working,,, along that line,,,, getting the dist. recurved would be a good investment,,,, putting a dual exhaust system that goes in and out of a single muffler and down one side... would be good making the air cleaner less restrictive would be good,,, when I did the mod the first time,,, it did not kill low end at all that I could tell,,, first gear was stronger,, and 2nd and 3rd was much stronger... just be sure to only cut out the partitions that go from side to side ,, not the one that runs down the middle .... the pictures on the sticky shows you how to do the whole thing,,, :Smarty:
