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A friend of mine has a motor for sale, a 454 that puts out 788 dynoed hp. Heres my question I asked him what it had and what he told me just didnt make sense. Can this happen.

19?? 454 block, stock crank polished, hyper 10-1 comp pistons, gm bowtie heads rectangular port with angle job and bigger valves. Dont know angle and size of valves. No head work. Pretty much stock head. Crane cam, dont know spec. but he said its mild. Single plane intake. Single 850cfm carb that was jetted. Ohh yea the blocks been preped

He told me it has 1 pass on the dyno and thats it and it made 788 hp. The reason I ask is my buddy hydroman916 has a well fully built 454 that puts out 654hp on the dyno. Hydros engine builder says its possible. Hydroman says only one way to find out, to take it dynoed. cost $$$

Can anyone shed some light... I know theres some guesstimating because of unknown of heads and cam. By the way he wants 1900 and has 6k into it.

Thanks
 

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mo balls than $cents$
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tell your friend that desktop dyno will let you make more than 1 pull per session:D i'm calling bs on 788, it takes some compression or a badass trick head/cam combo to do that.
 

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I guess you would have to look at this a couple of ways, it could potentially make those numbers but IMO at about 6000 RPM + and that would basically state "mild camshaft my ass".

The other way to look at it is he's asking $1900 for it and even if it made 300 HP, would be good deal.....

I am having a hard time with the 788 ponies though.

Use HP = Torque X RPM / 5252 as the formula, figure for approx 600-700 ft/lbs.

GT :)hand
 

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steelcomp was here
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With what you're describing, it's MOST unlikely it's making that HP, and it would be at a lot higher than 6000rpm if it was.
 

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With what you're describing, it's MOST unlikely it's making that HP, and it would be at a lot higher than 6000rpm if it was.

Agreed, you would be way better off buying my 350 inch small chevy, cast crank and pistons, at $1800 and 750 HP much better deal:D:D:D:|err

GT :)hand
 

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E-7 Sheepdog (ret)
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Yea, it's very likely to be a high-rev motor, IF it makes that HP (I do think it's unlikely too), at whatever power it does make.
 

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Resident Ford Nut
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A friend of mine has a motor for sale, a 454 that puts out 788 dynoed hp. Heres my question I asked him what it had and what he told me just didnt make sense. Can this happen.

19?? 454 block, stock crank polished, hyper 10-1 comp pistons, gm bowtie heads rectangular port with angle job and bigger valves. Dont know angle and size of valves. No head work. Pretty much stock head. Crane cam, dont know spec. but he said its mild. Single plane intake. Single 850cfm carb that was jetted. Ohh yea the blocks been preped

He told me it has 1 pass on the dyno and thats it and it made 788 hp. The reason I ask is my buddy hydroman916 has a well fully built 454 that puts out 654hp on the dyno. Hydros engine builder says its possible. Hydroman says only one way to find out, to take it dynoed. cost $$$

Can anyone shed some light... I know theres some guesstimating because of unknown of heads and cam. By the way he wants 1900 and has 6k into it.

Thanks
As a matter of perspective:

I know of a certain 565" Ford with a shit load of bad ass parts with 11.8:1 compression, a stout roller cam, heads that flow 450 cfm's, T&D 1.8 shaft rockers, etc, etc........ it made 935 Hp.

935/565= 1.65 hp cu/in.

There's a post over on the jet boat thread with an engine that made 1,040 hp I don't know if it's a 588" or a 632" but if it's a 632 that would be 1.65 hp/cu/in. If it's a 588" that would be 1.77 hp/cu.in.

In 1994 I was at the Popular Hot Rodding Engine Master's competition where Jon Kaase's 410" Ford belted out 701 HP at 6,500. That was/is one of the baddest ass single carb pump gas engine's ever built, with enough trick parts to fill a written page and before Kaase took it to the competition he had 75 dyno pulls on it. That 410" engine made 1.71 hp/cu.in.

The engine in question: 788/454= 1.74 hp per cu. in.

In all due respect your friend or the dyno operator is Full of Shit !!!!!!!!

Or that thing had nitrous on it.

It would be nice to know the cam specs and head flow #'s before I make a judgement ? (Roller ? @ 6,800 rpms )

Edit: Oh, one more thing; since this is a Big Block you're talking about here's a good read:

http://www.popularhotrodding.com/events/0404phr_engine_masters_challenge_2003/index.html

My friend Dan Crower built a 470" BBC that I helped on ($) it made 720 hp on the Crower dyno at 6,500( FYI: it was in no way near "stock" not even close, including bad-ass Brodix heads with 99cc chambers and 11.25:1 compression).

We think it would have finished in the top 4 of that year's competition. When we took it to Westec for dynoing it filled the dyno room with smoke from a push rod rubbing a hole in a intake port and sucked oil into the intake track.


Sleeper CP
Big Inch Ford Lover :D
 

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no one mentioned that maybe the guy or the dyno was on crack:)sphss

lol!!that has to be the badest near stock bbc ive ever seen,but ive heard and seen weirder shitRealityeither way for the money may not be a bad buy,hope it works out for ya,travis:)hand
 

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Those of us that actually dyno our stuff rarely, if ever, throw away our dyno sheets... Kinda turns into HP porn (if you know what I mean and I think you do!!). Ask to see the dyno sheets...

Building real HP is hard.... it's much easier to just lie, :)sphss... Sometimes I wish I took that route, it's much cheaper :D

If someone does have 788 REAL HP for $1600, I'll take 2 :)devil
 

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Resident Ford Nut
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Those of us that actually dyno our stuff rarely, if ever, throw away our dyno sheets... Kinda turns into HP porn (if you know what I mean and I think you do!!). Ask to see the dyno sheets...

Building real HP is hard.... it's much easier to just lie, :)sphss... Sometimes I wish I took that route, it's much cheaper :D

If someone does have 788 REAL HP for $1600, I'll take 2 :)devil
Our 710 HP 512" did make nearly 800 HP when the air temp sensor was hanging next to the header and picked up an intake air temp of 140 degree's.
The computer calc'd out nearly 800 hp :)sphss So I guess it's possible ;)
But on the first and only pull........hey you should have seen this fish I caught when I was 12 with a 5lbs test line it was this......................

Sleeper CP :D
 

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Just another Wannabe
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The only way that those numbers are even close to real, is if the heads were the GM bowtie SYMMETRICAL PORT heads. And then they would have made that number at about 7800rpms.

But, if it is a good engine and runs well and fairly fresh, it could make for a great engine for a nice price. Just throw the number out because it is not even close.
 
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