I have talked to race engine builders who pretty much do the same thing. Like for roundy round sportsman cars that can't do headwork, they flow 20 sets of heads, one set will usually outflow the others considerably and several sets are slugs, due in part to sloppy casting methods and core shift I suppose. I wonder how many engines they had to go through to get one that would make 350 and what the low end of the bunch did. But I also don't think you can take the Holman and Moody cream of the crop numbers and throw that blanket over all the production cars as a generalization of expectation..

Holman and moody might have squeezed 400 from a 312 but I would like to see dyno proof that a stock HP one ever came close to 360 hp. That being said, I once had a conversation with a retired Highway Patrol officer and ask him what his favorite car was. He served from mid 50s to late 70s and had all the 440 mopars, 427 scrubys ect. He said his favorite was a 57 Ford 300 with a 2 fours 312 and over drive. He never had a 427 Ford though but did have a 64 solid lifter P code 390, which were rated a 360 hp IIRC. Also he never said the 57 was or wasn't the fastest car, just the one he liked best.

I'm not knocking Ramblers, I have always liked them a lot. Heck I have a wonderful dog I named Nash after the Nash Rambler. Back in 1966 I rode in one from Key West FL. to Asheville N.C. and was totally impressed on just how smooth it was. I've always respected the power of the 289 and 327 engines they had, if you didn't they could show you their tail lights very quickly. I was also impressed with the front seat backs laying all the back for resting, why the big three didn't do that I'll never know.
     I was speaking about the hp all these cars were making including real hp that was not published. Weight does play into how well these cars ran, for instance the birds and Fords ranged in the 3600 to 3800 lbs. where as the 66 mustang shipping weight was around 2500 lbs. This will make a difference in speed of course. And yes I like mustangs too. Big difference with 1100+ lbs between them in weight. The Studebacker was another car ahead of it's time in design, the 1953 is still my favorite. All these cars are great and deserve our respect.


-Gary Burnette-

Guys, we can debate "mid-size" until the cows come home. I Think if you check shipping weights and wheelbase sizes you will find the 300  series Fords and the Rambler Rebels were actually fairly close.
  As to Hp figures, my 57 F code made 372 HP on the dyno while running out of fuel! The factory fuel pump could not keep up with the carb.  Later I discovered that the supposed 6 valve F code pump was a standard pump with the boost fitting added. In other words I got ripped off.
   This motor has stock sized valves and camshaft timing. The cam is a replica of the optional F code cam, not the "D" cam as usually installed by the factory. It is legal and was used in all the race cars and most street cars. Supposedly added 15 hp to a D code (270 to 285). NHRA, and IHRA both factored the motor with the Standard Cam to 340 hp, they still won their classes, So the outlawed them.
  As Gary mentioned my can has run in the mid 13's on 205-75 radial tires, with mufflers and at a scaled weight of 3800 + lb.s with it's overweight driver. It has also run 105.7 mph in the quarter which would equal a high 12 second quarter with slicks and a decent rear suspension. This speed was used by one of the Owners of the race to calculate the REAR WHEEL Hp of the car at 342!
   I race with an organization called the Pure Stock Muscle car Race. Look it up at PSMCDR. The rules are very restrictive, no cheater slicks, stock everything on the motor. We are allowed a 2 1/2" exhaust system and electronic ignition, period. Never have seen one of the vaunted '57 Fuelies or tri-power Pontiac's. Or a Chrysler 300, or a Plymouth Fury there yet. May not ever with the value of those cars increasing every day.
      I invite anybody in the midwest who's curious about this to the race in Sept to come to Stanton Michigan and watch. You'll get to see about every 60's or 70's musclecar ever made (yes AMC and Studebaker) run full out. And the are stock, cheaters will be told to leave. 


Frank/Rebop

Bristol, In ( by Elkhart) 

In 1966 I was running the original stock 312 in my '57 T-Bird. I had added the factory dual quads, 3 speed all syncro trans with Hurst shifter. 3.89 open rear end with home made traction masters.  A friend had a '65 Mustang convertible, 289, 271 horse HiPo, 3.89 rear end and 4 speed. On an 1/8 mile drag strip with me running open exhaust and 6" cheater slicks I would beat him by a car length. He had street tires and closed exhaust. Same track with street tires and closed exhaust on my T-Bird he would beat me by a fender. Rat racing on the highway on the way back home after the races it was pretty much neck and neck. My T-Bird weighed 3600 pounds. My '57 Ford 2 door Custom 300 also weighed in about the same 3600 pounds. Not sure exactly what the Mustang convertible weighed but I am sure it was less than the T-Bird. Your performance may vary but that was my experience back in the day.

I’ll add some more fuel to this fire.  An older Ford Engineer who was present during the ’57 Ford era passed on to me that Holman and Moody would dyno all the 300HP engines before tearing them down for blueprinting for Nascar.  If they didn’t make at least 350HP in their delivered out the crate condition, they were simply returned back to Ford.  After blueprinting, they made an honest 370+HP with all factory components.
 
This explains why the 283HP 283’s couldn’t even begin to keep up with the 300HP Fords.  At this point, it’s pretty much common knowledge that the 300HP Fords were grossly underated.

Lorena, Texas (South of Waco)

A '66 Mustang weighs less than a '57 T-Bird, so it is logical that not as much power is needed with a '66 Mustang to equal or surpass the performance of the '57 T-Bird.



Lawrenceville, GA

Keep in mind if the super charger is not set up correctly then the outcome will not be optimum. I not arguing just expressing what I've seen, been told by Nascar racers, and what I've read and heard from others.


-Gary Burnette-

Frank Rice's 1957 ford custom 300 is a stock 312 with a Paxton dynoed at 370 hp and runs in the thirteens in the 1/4 mi. Others on this form know this as fact because they and myself watched him do it and we have raced together as well. The cars were equipped with 3 speed T-85 transmissions 3.70 rears for 57 and 3.92s for 56. It takes a lot of power to put one of these cars in the 13s.



-Gary Burnette-

      370 hp for a  factory   engine is blown right  out of perspective   The  engine was  rated at 300 hp and  were  known to  make as much as 340!  
My uncle had a 1957 T bird with  a super charged  312 and  I used to own a 1966 289 with  Paxton super charger   hp  the mustang would eat the T  bird a live and it  was 325 hp!