Author Topic: Horsepower  (Read 2127 times)

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Offline 1styellowboss

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Horsepower
« on: September 28, 2009, 03:03:50 pm »
I have read many times that the horsepower rating on the bosses was underrated. Does anyone know what the real horsepower was on these cars? I would love to know.

Offline TACoupe

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Re: Horsepower
« Reply #1 on: September 28, 2009, 03:22:53 pm »
I've read over the years that it would have been 315 to 320. I wonder what the correction factor would be to today's ratings? Anyone know?

             Roy

Offline EricDickerson

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Re: Horsepower
« Reply #2 on: September 28, 2009, 04:07:40 pm »
I could be wrong, but based off Magazine 1/4 mile times in 1970. The horsepower numbers sound about right to me?

I know it could be a bit off, especially with the factory Polyglas GT tires they used.

Eric

Offline nadine

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Re: Horsepower
« Reply #3 on: September 28, 2009, 06:14:02 pm »
I have a dyno sheet on one that was very stock,BUT it was dynoed with headers
no exhaust and a belt just turning the water pump.It made 350 standard corrected
on a super flow .@5800

Offline Stonewall

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Re: Horsepower
« Reply #4 on: September 28, 2009, 06:28:17 pm »
My understanding is that they were promoted as south of 300hp for insurance purposes.  RWHP at 1:1 (302) was significant at the time.  I don't think they were that far off in stock form.  Maybe 305-310?  Just a WAG.


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Offline T-Handle

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Re: Horsepower
« Reply #5 on: September 28, 2009, 10:01:00 pm »
There's a formula that takes the weight and MPH figures to give a HP rating.  Anybody?

Offline 68RCodeConv

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Re: Horsepower
« Reply #6 on: September 29, 2009, 12:50:45 pm »
I look at it this way.

A stock Boss 302 with good traction will run in the high 13s.

An early 90s 5.0 Mustang with good traction will run in the high 13s.   It was rated at about 225 hp (net).

There you go.


Offline JoshBolger

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Re: Horsepower
« Reply #7 on: September 29, 2009, 01:59:29 pm »
I've read over the years that it would have been 315 to 320. I wonder what the correction factor would be to today's ratings? Anyone know?

             Roy

The SAE test then and now is way different. I believe then it was no accessories, high flow exhaust air filter and tuned. Today, it is basically as installed in the car. I know my 2005 GT made 290 at the tire brand new, with no mods. Depending on the source, add 25% to get flywheel numbers 290x1.25= 365
Josh Bolger
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Offline captain morgan

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Re: Horsepower
« Reply #8 on: September 29, 2009, 03:44:25 pm »
Thought it was around 325 ?
You know why divorces are so expensive ? Because they are worth it! Says me and Willie  Nelson!

Offline gt350hr

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Re: Horsepower
« Reply #9 on: September 29, 2009, 04:35:30 pm »
   I checked with Dan Nowak who built several "stock" engines for dyno testing at Ford in '69 and the figure with waterpump only and dyno headers was around 350.
 With stock manifolds and full operating smog/alternator but no P/S, it fell to 315-320 on Fords dyno. They did run better the longer they ran. Simply advancing the stock camshaft by 4*s was worth 15-20 hp over the as delivered engine, but the powers to be kept it retarded for production. Now days that's an easy way to wake up a "pure stock" Boss.
     Randy
'66 GT350H (6S477)1of 18 white w/blue side stripes - drag raced mostly w / Boss 302 power for 35+ years
68.5 Cobra Jet fb  white w/blue c stripe 4spd
sorry never owned a Boss car just engines
cover Car Craft July '77 with my Boss powered GT350
cover/article Mustang Illustrated Fall 1987 w/all aluminum SK 351 Cleveland powered Mustang II
cover /article Modified Mustangs Feb 2011
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Offline BOSSJIM

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Re: Horsepower
« Reply #10 on: September 29, 2009, 06:56:27 pm »
350 sounds about right. Hot Rod Mag made the claim years ago.

Offline 70goldboss

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Re: Horsepower
« Reply #11 on: October 02, 2009, 10:29:34 pm »
The sheets on my engine with headers on the dyno with balanancing, blueprint etc. show 377 hp at 6200 RPM

John

Offline Nitro

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Re: Horsepower
« Reply #12 on: October 02, 2009, 10:47:59 pm »
In 1970, the Boss 429 was rated at 375HP..
Ya,right, how about 435HP in stock form..
All  engines are capable of 50% OR MORE HP.................
They tuned them down so as they would live a little longer
and to appease the insurance type leches...
the Boss 302 was more like, 350 HP and the Boss 429 was at
450 HP................
Nitro.
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Offline Stonewall

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Re: Horsepower
« Reply #13 on: October 02, 2009, 11:14:36 pm »
350 sounds about right. Hot Rod Mag made the claim years ago.

Maybe at the crank, but not to the rear wheels.


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Offline Boss302Fan

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Re: Horsepower
« Reply #14 on: October 03, 2009, 09:26:50 am »
325 HP is the highest I have heard...