PONTIAC - stock Pontiac Super Duty 421v8/405hp vs stock Chevy 409v8/409hp on DYNO

WATCH THE VID TO SEE HOW CLOSE THEY DYNO TO THEIR FACTORY 405hp/409hp ratings. Growing up.....Pontiac/Oldsmobile old timers/EXPERTS who taught me most of what I know, often told me Chevy rated their horsepower in a more optimistic way than say Oldsmobile or Pontiac. I've even heard Pontiac rated/tested their engines in a 100 degree room, compared to Chevy in a 60 degree room. These dyno results seem to reflect that some of what I heard was true. Both of these engines are great, but the results do seem to show that Pontiac was not rating their horsepower worrying if it would cause "songs to be written" about their engines .... like the great song "She's real fine my 409"--(Chevy).

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  Autos & Vehicles

[KoDBeast]

Looking at the 409, there is a spot around 5538 RPM that its producing 425.2 HP. it continues staying around that area before finally freezing at the 406 mark, making around 430 ft/lbs. The 421 has .25 more compression, a few more cubes, and much more horsepower (488) but 470 ft/lbs. Seeing how the 409 is a truck motor it seems to give out more torque per cubic inch, which kept it in the running. not a bad test though, its nice to see the 409 going head to head with a close rival.

[1967PmdGto]

Good points. Yeah I saw that 425 too, so I'm not totally sure how they arrive at the figures they got, maybe they discarded it because the dyno was not yet loading the engine at the proper rate at that time, or something. AND YEP THESE ARE BOTH GREAT MOTORS.

[citydriver]

406?? wayt i saw 425hp on the 409 dyno

[1967PmdGto]

I saw the 425hp too. Not exactly sure how the dyno works but we know they're loading the engine (not free spinning in neutral) to simulate car weight. When I was in GM school they loaded my rebuilt transmissions on a similar device to see if it would hold together under a real car load. I don't know if the 425 was human error on these guys part, or maybe the engine was not in the right "load window" yet for the machine to consider it a true 425hp, who knows?

[biscaynenick]

421 Had a song in 1962 by the Super Stocks called "Wide-Track" ..."Red hot and cool w/a big chrome tach-got a 421 in front w/lotsa talking back. When it comes to the power shift I really got the nack and I never been beaten in my new wide-track......Big heavy clutch she's ready for some action and she'll never break loose w/the posi-tracion...Dual carbs are thirsten they need more gas theres nothin on the road that I can't pass"!!!!

[1967PmdGto]

Hey someone finally got that WIDE TRACK song up on ytube that you mentioned! I had told you a year ago it was no where to be found. Now I see 7 months ago, or 3 months after I checked, they got 2 versions of it up on ytube.

By THE COMPETITORS

watch?v=CoqhMLKG314

By THE SUPER STOCKS

watch?v=M7AJIuTn4PQ

[Trendyrapslut]

pontiac putting another chevy to shame

typical

[PontiacAlfaHSV]

Boom, Pontiac motherfuckers

[Andreas Ekdahl]

Pontiac 4 ever

[bg147]

I like what both gentlemen said about not racing these old motors and preserving them as historical items.

[kadron56]

406?????? I saw 425 on the 409....

[kennethrobinson11231]

This was a Ford People doing this show. Ford even use a different engine on the Dyno so they could look good. That 409 made over 425 if you slow the tape down.

[WickedTornado]

Yeah, me too. I also saw the Poncho get much higher numbers on the dyno too.....at least I thought I did. What gives, guys? Were they deducting for something related to the dyno or ??? Thank you.

[WickedTornado]

OMG...I cannot believe that I've surfed into this shootout. I'm almost 60, and for decades I have been waiting for one of the magazines to sponsor a dyno-shootout with STOCK engines. I've long wondered about the truth of all the musclecar engines power/torque ratings. This is fantastic! I hope part 2 is available here somewhere. THANK YOU TO WHOEVER POSTED THIS! joel in tucson

[ztwntyn8]

She's real fine my.... 421 ha ha ha ha yeah, in your face.

[Sparkinrailz]

Stroke that 409 to a 4 inch stroke and then compare.