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Discussion Starter #1
So my curiosity got the best of me today and I was wondering how all these motors stacked up against each other. I chose these motors because they are all very similar in displacement, they were all readily available back in the day, and with the exception of the Pontiac, were all big blocks. For comparative basis let's assume these were all 1970 motors with no rare options such as Ram Air IV, dual quad setups, etc. All of the horsepower and torque ratings these cars had from the factory were conservative to say the least for insurance purposes. What I would like to know is how these motors compared to each other, brand new back in the day, side by side. I'm not necessarily interested in opinions. This is a Pontiac forum... obviously our opinions will strongly lean towards the 400. I'm more interested in factual information. So throw some numbers at me! Peak horsepower and torque and at what RPM's, bore, stroke, airflow, compression ratios, engine weight, whatever you can think of.
 

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I have driven all of the above, at one time or another. I have laid waste to all of the above with a Pontiac 400, including a 396 in a '67 Firebird when I had a burnt exhaust valve. Pontiac under rated their engines HP wise, and the others tended to over rate them. Don't get me wrong, they are all strong engines. It's just that the Pontiac has a bit more oomph, especially down low in the RPM range. The 390 Ford is the slowest of the bunch, with the 396 and 383 being about the same. I've driven Chevelles, RoadRunners, and Fairlanes with these engines, and they were all slower than the lowly 400 Pontiac V8. As for actual numbers, you can research 1/4 mile times of the day to get a good picture of what was what. Back then (late '70's), I always found that the unmodified 383-390-396 engines ran better than the back yard modified ones, though.
 

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That's pretty interesting. I'll look up some things here in a bit. But now I have to ask, what has laid your Pontiac 400's to waste over the years??
 

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LOL....Roger That is right. My 389 tripower '65 will eat the 400 in my '67 for breakfast. But the '65 is a 4 speed with steeper gears and weighs less. With the '67 400 in my '66 4 speed 3.55 4bbl GTO back in the day, the only guy who beat me was a '69 Roadrunner with a built (5k in the engine in 1979 dollars) 440 and a Torqueflite. But I was selective. I didn't race that Camaro that pulled a wheel stand, or my co-worker with a '67 Dodge Dart with a pumped 440 and a 4 speed, and I picked my battles. Raced 'like' cars. But the garden variety encounters were no issue. Raced an LS-6 454 '70 Chevelle and beat him, as well as a bunch of '60's 'Vettes. A friend had a bone stock '67 GTO with an automatic and a 2.93 rear gear, and he beat everybody except a guy in a Shelby GT500 and a guy in a Superbird with a 440 sixpack. We paired him up 3 times against a built '69 SS 396 with 427 parts, and he blew the doors off of the Chevelle each time. I tuned and drove a '69 383 Roadrunner with a 4 speed, a '66 Fairlane 390 GTA, and a '66 SS396 Chevelle, and none were a match to my '66 GTO with a 400 Pontiac under the hood. I owned a '66 Coronet with a 375HP 440 and a 4 speed, and it was slower than my 389 powered '65 GTO. I sold the Coronet.
 

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Well here are the "official" numbers:

383 Magnum 4-bbl: Bore/stroke: 4.25 x 3.38. CR: 9.5:1. HP: 335 @ 5200. TQ: 425 @ 3400
Ford 390 4-bbl: Bore/stroke: 4.05 x 3.78. CR: 10.5:1. HP: 325 @ 4800. TQ: 427 @ 3200
Chevy 396 (402 in 1970): Bore/Stroke: 4.1259 x 3.76. CR: 10.25:1. HP: 350 (no RPM found). TQ: 415 (no RPM found)
Pontiac 400: Bore/Stroke: 4.12 x 3.75. CR: 10.5:1. HP: 345 @ 5000. TQ: 430 @ 3400

I was surprised to see such a low compression Ratio for the 383 Magnum. I wish I knew the RPM's for peak horsepower/torque for the Chevy. Anyone know the answer to this?

Now the only problem I have with these figures is that these are what the cars were rated at from the factory, and we all know these numbers are BS. What I would like to know is these engines' actual power output measured on a Dyno in pure stock form. Does anyone have access to such information, if it even exists? I've seen the youtube video where they put a Chevy 409 up against a SD 421, which was cool, but I'm more interested in the engines the average joes had under the hood back in the day.
 

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Discussion Starter #9
This is very true Bear!

The reason I started thinking about all this is because my good friend is rebuilding a 1970 Challenger with a 383 Magnum and we got to discussing the issue. Also Chevy guys love to talk sh*t but I don't think I've ever heard of an SS 396 consistently outdoing a Pontiac 400. As for Ford, from what I've seen the 390 was primarily a truck engine with nothing special, but they were used in some Fairlanes and Galaxies. The 383 Magnum might have an advantage because of the bore/stroke ratio, and it has a lower compression ratio, so it's got room to grow if you want to build it up.
 

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Again, Orion, this might be just me, but I drove dozens of these cars when they were 8-12 years old back in the day, and my take on it is this: the only Mopar that could compete with the Pontiac was a 440 with multiple carbs. I never drove/raced a 426 Hemi, but I drove 426 and 413 Wedges. Raced a friend with a 340 Scat-pak dart with a 3.91 rear gear, and i had him by a fender until 80mph, and then left him in the dust (I was driving the '65 GTO I still have). 383's were '0K', but nothing to write home about. 390 Ford was the slowest of the bunch. I must have raced against 50 SS 396 Chevelles and Camaros, and none of them ever even came close to my 389 or 400 Pontiac. The actual closest race I had was against a friend with a '69 Z-28 with a built 302, dual quads on a cross ram, 4.11 gears, and a 4 speed. I was running my '66 GTO with a $150 junkyard '67 Catalina 400 engine with a 066 (2bbl cam), 3.55 gears, 4 speed, and tripower. I beat him by a single car length. He never lived it down, and that was over 30 years ago. Still pissed. A $4k blueprinted engine in a light car losing to a junkyard engine out of a 4 door sedan that used to be a 2bbl. In a heavier car. Also, realize that only Pontiac and Olds had the Hurst shifters. The Chevelle had the crossmember mounted Muncie shifter, which you couldn't speed shift. (it would bind with engine torque under WOT). The Chrylsers had the notchy, long throw Inland shifter (slow to shift), etc. The Pontiacs were ALL AROUND better equipped cars: just look at the interior/guages of a Pontiac and compare them to a Chevelle or Fairlane or Roadrunner. Not even close. When I was in high school, all of these now high dollar Mopars were everywhere, and were $500 cars. I chose a '66 GTO instead, because it was fast, good looking, and most of all, much higher build quality than the tinny, cheesy Mopars. I worked on a ton of these cars back in the day, and could go on and on about the crappy Falcon based suspension of the Fairlanes, the loose steering and poor quality of the Mopars, and the over rated, underwhelming performance of the Chevelles. Hopefully, other old guys with similar experience will give their 2 cents............
 

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That's pretty awesome. And the main reason I'm asking. I'm only 25. I didn't grown up racing between stop lights. When I was still driving my car the only people who challenged me to race were stupid tuners and rice burners. And I wouldn't give them the satisfaction. And any muscle car today that is bone stock and all original numbers matching no one wants to race because they're too valuable. So I'm just trying to figure out how things really stood on the street, because the factory ratings never told the real story.
 

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RIght On. Also, keep in mind that my experiences are mostly "Day Two". My friend Andy's '67 GTO with the 2.93 was indeed, bone stock 100% down to the whitewalls and hubcaps. The lady we bought it from got it brand new for a high school graduation present. We picked it up as a 12 year old, 90k mile car for $1350, and the engine had been overhauled at Doten Pontiac at 80k miles. That car ran like a scalded cat. Especially out on the highway. I remember cruising 110-120 at about 4100 rpm. (had the rally dash). Thing is, in the late '70's, these cars were cheap, used, gas-hog cars. Most wore original paint. I had the cleanest '66 GTO in town, because it was just repainted. NOBODY was fixing these cars up to look nice. Most had mags, headers, and air shocks. My GTO's didn't start getting 'noticed' until the mid-late '80's, when the prices and level of the cars started to rise. You saw more 'restored' cars then. But in the late '70's, a decent 4 speed '64-'67 goat could be had from $400-$1500. They were simply used cars. There WERE no fast Hondas back then. Or fast domestic cars, either. If you wanted to go fast, you bought a cheap 10 year old used car, whatever brand. Like I said, I drove them all, but the GTO was the perfect combination of style, performance, and interior treatment. They got it perfect. The '68 Charger looked great, but the dash was cheesy and the window cranks fell off. The ones that were the equal of the GTO back then? A friend's stock '70 Olds 442 with a 455 and a TH400....car was a bomb, and a co-workers '69 Buick GS Stage 1 4 speed convertible.....that car was in GTO territory, as well. In fact, the Buick GS's and GSX's were very, very fast, faster than a lot of GTO's and even beating out the 426 Hemi in a Roadrunner on a road test at the strip.....and the '70GSX was an automatic, air conditioned car with a 3.23 rear end.....the Hemi was 4.10 geared, had dual quads, and was a 4 speed....and lost to the GSX in the 1/4 mile. Buicks and Old's got my respect then and now: the build quality was equal or superior to the Pontiac, but the syling wasn't quite as sharp. Chevrolet? At the time, the lowest price GM product, entry level, and it showed. The only reason they were and are so popular is because they were cheaper to buy and more were produced, so more people had them and remember them. They certainly were not better cars.
 

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The Street was different in 1969. The first car I bought was a brand new 1970 GTO. ram air iv car. I grew up in Brooklyn and street racing was king. Here are the rules you kept in mine. A factory Chevy 396 was good but can be beat, A factory LS6 454, will blow your doors off if the driver could drive. Mopar a factory Street hemi, most owners could not get them to run, hard to tune. could be beat(Mopars are very heavy). A tuned 440 That was tuff to beat, but It was possible. The Pontiac 400ra IV was very good, but most of it was toque great low end not much top end. The one thing you had to watch was the Chevy guy with built motors, In 69 you could get all kinds of speed parts for Chevys even aluminum heads, Pontiac was different almost no street, speed parts that we could get hold of. So the answer to your question is apple and oranges. I left Ford out because there were not many around the area I was in and the ones we knew all had 351's and there were junk!!!!!
 

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Discussion Starter #15
That's pretty interesting. I'm well aware that the Hemi's were difficult to keep running right. The heads were full of cheap junk parts until you put a few hundred bucks into them. A properly tuned 440 though was much more streetable and could still tear up the pavement. Ford really only had two decent motors that I'm aware of: The Boss 302 and the 429, but I don't know much about Fuurds. And yes, the Olds 442's and Buick Stage 1's were pretty dominant, especially for being perceived as a grandpas car, and I don't particularly like the styling either (Except the boattail rivieras and the Grand Nationals of course!). So the general consensus seems to be that of the stock, run-of-the-mill power plants that were readily available at the time, Pontiac was king. Even with regards to the rare, high performance engines, the Ram Air II Firebirds consistently place very high in pure stock drag racing today. Not too shabby.

So I've been looking around and haven't found very many engine dyno runs on these engines in bone stock form, except for the 396. I'm still curious what kinds of numbers a bone stock Pontiac 400 would produce. Everyone who does a bone stock dyno run typically has a rare performance motor, which is cool, but those were hard to come by back in the day.
 

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Yes, ten years earlier and on the east coast, different story for hot Chevys and parts availability from dealers. Not the same dynamic as the west coast, ten years later. It was cheap and easy to build up a big rat motor and be competitive in the late '60's, though. Luckily, I never faced off against any of those cars. Just the 'regular' SS454-402-396 Chevies. I agree with the wedge motors by Mopar: the fastest ones seemed to be the 440's with multiple carbs. They were pretty bulletproof. In the end, a lot of the equation was the skill of the driver, especially those of us who were rowing a 4 speed.
 

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Discussion Starter #18
Found a video of an Olds 442 dyno pull. The W-30 455 made 510 lb-ft of torque and 427 horsepower with stock heads, intake, exhaust, and quadrajet. BUT it was punched .030 over which probably gave it a little extra power.
 

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Not much.....less than 10 more cubic inches. Olds, Buick, and Pontiac under-rated their figures. Chevy and Mopar and Ford tended to over-rate them, especially Chevy. I raced more than one 375 HP small block corvette or 375 HP big block Chevelle with a mere 360 HP GTO, and beat them easily. Very hard time believing that the little 375HP 327small block Chev actually put out that kind of power...if it did, the torque must have been about 300 foot pounds. The stock Pontiac? Over 425 foot pounds, usually more.
 

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Well I'll hail in with memories from deep within the organs of Motown...where these beeotches were conceived!

On the street? Big Block Chevy, always, and not every one but dominant in most cases. My memories and experiences are also "day 2". 390 Ford? Had a 63 390 Cadillac in SWB 62 Ford unibody pickup (read that as lighter than the Caddy that gave up it's motor) and that ol thing just flew. It didn't have long legs, but in an 1/8mi sprint it would piss off a lot of cars including a 73 350 Camaro with a 4spd. Any of the 390 cars didn't wanna play. Had a 70 383 'Cuda. A real "BS23N..." car with a 4spd and 3:55s. 14.21 at 97MPH on slippery L-60 tires at Detroit Dragway. Even feathered off the line 2nd gear would start a new "burnout", and as to it's build qulity? Hamtramck Dumpster!! "CLANG-SQUEEK-BUBUMP" was the order of the day even after a quality restoration of the body (though not body-off). Sexy car, and I could look at it all day from a rear 3/4 view. Had a 440 GTX for a time and it had the same dumpster traits but it was pretty fast. Just don't leave the ashtray open when you bang 3rd gear! OOUUCHHH!! I've had a few BBCs under foot but never a 396. The 396 in my neighborhood was no punk. Being Motown there was no shortage of knowledgeable tuners and they cruised with confidence. I had a slug 454 from a 74 Blazer in Chevelle. With 3.31 gears it had some spirit but it took a "blue bottle tune up" to gain just a little respect. My Pontiacs? Sorry kids, they were the slowest of the lot. I had a 70 GTO with a 73 T/A 400 in it. Fun, torquey, sure-footed, but no match for anything else I had. It was an automatic with 3.08 gears. Had a 69 'Bird that got a 400 2bbl from a 69 wagon installed out of necessity. Also with 3.08 gears, 16.40s in the 1/4mi at 86MPH. Had a 69 Grand Prix with 421 transplant. Very, and I mean veerry long legs. Not a 1/4 mi car at all but serious top end.

The best of the best under my foot? 69 Boss 302. Never took it to the track but the log book that came with it noted 12.80s for the day. This was an Autocross car more than a drag racer but I was a drag racer and knocked many an unsuspecting car back with a lowly "302". Don't think for a minute that I thought that's all it was. Canted monster valves, 780 Holley, 4spd and 4:30 Det Locker. 2nd was a 68 GT500KR with 428CJ and 4spd hooked to 3:55 gears. Stomp it from a 50 roll in 4th and it felt like passing gear when the secondaries opened. A heavy and solid "man's car" in all respects. There were a couple fast Pontiacs around but the BBCs and Mopars ruled the streets. My 383 was no punk but the rest of the car flat out sucked.
 
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