What are good methods of estimating horsepower?

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Okay troublemaker let's get back to the original question have a good way to estimate horsepower? I mean even you went to that track one time to get a lot of your calculations correct? Let's point this young man towards a safe place to play with his ponies or at least get used to them. Let's not entice a young man with a lot of newly found horsepower to act as if he has the experience some of us older guys have of course if he's young enough he probably knows more than us LOL!
AJ/FormS said:
Hey that goes without saying.
But why bother stabling 400 ponies under the hood, if you can't let 'em run once in a while. They need their exercise.
I mean it takes less than 50 hp to maintain 65 mph, so why do manufacturers supply us with cars that can exceed 50 hp?
I'm not driving 3 hours to the one racetrack in the entire province, to blast off a couple of runs that tell me exactly what I already know.And then drive 3 more hours home.
99.9% of the time I am a good law abiding citizen. But every once in a while I hit it,to redline, in 1st/over, which is 65.8 mph.And I may not be traveling in a straight line. And the tires may not have stopped spinning.And I have a reserve fund if Mr policeman does not find it as exhilarating as i do.
I pick my spots, and my times, and I keep my cool. In 16 years it has cost me just $369.Can. Which might be $250 US. If it makes any difference, both tickets I received were for Imprudent driving. Not speeding. Not Dangerous driving. But Imprudent driving. Which is a catch-all ticket for spinning tires excessively,not signalling,and driving too slowly,etc.
One was for doing a 360*. About 150ft or more in diameter (oval actually), on gravel, around a couple of defunct silos, on private property.Copper said" you know you can't be doing that here,eh? But you sure do it well. You know I'm gonna have to write you up,eh.";his words.Canucker.
The other was for spinning tires up to 30mph, on a public road,in a 35 zone.Copper said he had been following me around for a while, and that I "looked like a trouble-maker", and I finally slipped up. He was hungry and wanted to go for lunch. Serves me right for a custom paint-job.......I don't know how I missed him,lol.
Click to expand...
 
j par said:
Okay troublemaker let's get back to the original question have a good way to estimate horsepower? I mean even you went to that track one time to get a lot of your calculations correct? Let's point this young man towards a safe place to play with his ponies or at least get used to them. Let's not entice a young man with a lot of newly found horsepower to act as if he has the experience some of us older guys have of course if he's young enough he probably knows more than us LOL!
Click to expand...
I'm 33 :-) And yes, I don't have a lot of experience with Muscle cars, but I have had lots n lots of regular speeding tickets, and reckless driving/ excessive speeding tickets, so I don't intend on getting any more of those...

I do remember sliding sideways through the gravel in front of the high school like a madman right in front of the school cop, and several times jumping my 79 ford LTD in a farmers field off of burms and into dry creeks and generally being a very entertained jack *** in the open areas of Idaho...

I know now that i could have gotten in a bad wreck a few times or been in jail several others... Thank the Lord He kept me safe! I'm a dad now so I'll tone it down quite a bit, but some fun will still be had :-)
 
LOL... Ok. I have Pipemax and Engine Analyzer Pro to give me an idea. I really never use the chicken.

In terms of estimates... The easiest I've come up with is to take the peak lift of the intake valve for the cam one has, and research the flow ratings available for that head type for that max lift. If the engine is a performance engine (meaning bolt-ons like headers, intake, carb, good performance ignition, etc) than multiply that flow figure by 1.9 and that's about what the engine should make at the crank. Compression ratio will only serve to move the power peaks around, not deliver more or less. So you only need the flow for the cam at max intake lift.
Example: 340 with X heads, stock replacement pistons, the RPM Air Gap, a set of cheapo Hedman headers and 2.5" duals, recurved factory distributor, and the Comp XE268 cam. Properly done, stock port X heads with a modern performance valve job should flow around 215cfm at .480. Cam lift is .477", so figure 215 x 1.9 = 408hp.

I'll add - poor machining, wear, porr tuning, or any number of other things will lower that number, and conversely high quality everything might add some. The biggest deal is the flow rating. There are a lot of very "happy" benches (or happy machinists?) - even posted on this site. Ultimately the proof is on the track accelerating a given weight to a measured speed over a 1/4 mile.
 
I'm not trying to be a buzzkill here and having fun is quite the point with a car like that but there's a time and place for everything and getting out here and encouraging people to do it anywhere else than in a safe environment is at least not what I recommend.
1970dartcustom said:
I'm 33 :) And yes, I don't have a lot of experience with Muscle cars, but I have had lots n lots of regular speeding tickets, and reckless driving/ excessive speeding tickets, so I don't intend on getting any more of those...

I do remember sliding sideways through the gravel in front of the high school like a madman right in front of the school cop, and several times jumping my 79 ford LTD in a farmers field off of burms and into dry creeks and generally being a very entertained jack *** in the open areas of Idaho...

I know now that i could have gotten in a bad wreck a few times or been in jail several others... Thank the Lord He kept me safe! I'm a dad now so I'll tone it down quite a bit, but some fun will still be had :)
Click to expand...
 
j par said:
I'm not trying to be a buzzkill here and having fun is quite the point with a car like that but there's a time and place for everything and getting out here and encouraging people to do it anywhere else than in a safe environment is at least not what I recommend.
Click to expand...
Quite understandable... you're a good egg.
 
Happy dynos sell engine builds! One of the most inaccurate dynos I have ever seen is right here on fabo! The dragstrip doesn't lie!
 
Set a $20 dollar bill on the dash on the passenger side. Get someone to sit there and slide the seat all the way back.

Tel them you are going to drive "light to light" and if they can grab the $20 its theirs. Proceed to "floor it" to the next redlight.

if they grab the $20, the HP is low, if they cant grab the $20, its right where it needs to be.
 
That wouldn't work in my car.......
When I hit it,my keys are jumping out of the ignition and, and are headed south.I expect the $20 would be in the passengers lap, And I'd be broke before too many tests went by,lol
But I can't find anybody to ride with me anymore, anyway. All the people I know have sore necks....
 
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