OMG!!! Twins Rock part II

[Jetpilot]

There is ALOT more to calculating HP than just plugging in #'s on the internet. How about drag, traction, gearing, HP rpm range, torque range, friction, etc. Your quote of it is physically impossible to move that amount of material that distance in that period of time without generating at least 637hp. is wronge... ...



The dyno is not perfect but it is really the only tool we have to accurately measure HP under a given set of conditions.



Doug

 

[Lightman]

1/4 Mile is 1320 Ft not 1330 Ft maybe that would throw off your calculation

 

[Mark_Kendrick]

Originally posted by Lightman

1/4 Mile is 1320 Ft not 1330 Ft maybe that would throw off your calculation

it was a typo

 

[Mark_Kendrick]

No it is not wrong.



Drag detracts not adds. The formulas used assume that you are operating in a vacume. in air it acually takes more power to go that fast.



All of the factors you list are reasons for increasing the hp exerted not decreasing it.



for example, traction would limit the power that could be transfered to the ground. So a traction limitation would mean that he was 'sand bagging' a bit to keep from slipping the tires. This implies more power not less.



The combination of speed, ET, & weight allow a precise mesurement of power.



Why does a 572hp truck exert 637hp at the track?????

 

[Diesel Freak]

Originally posted by Mark_Kendrick

Why does a 572hp truck exert 637hp at the track?????

you can load the truck harder at the track than a Dynojet can.

 

[Mark_Kendrick]

That didn't take long



way to go DF!!

 

[mschoenheider]

Mark,

Your formulas and Internet calculators add in for all sorts of thing like aero drag, weights of tires and wheels, and the shape of a hp curve. They give you a peak hp, which is impossible to calculate given as little info as the time and trap speed. If you just calculated average hp based on change in kinetic energy divided by the time it took the truck to get down the track, that truck only averaged 369 hp. I did neglect the kinetic energy of the rotating tires, but that would not add many hp. Gas motors and diesels have much different shapes to their HP curves, so therefore a diesel would perform closer to the average power number than the peak hp number those Internet calculators provide.

 

[Jetpilot]

Mark,



You need to go educate yourself on physics, pay close attention to the equations used by these HP calculators... ... What I said before stands, even the formulas writers agree that many assumed conditions are constant (read the fine print on some of the websites). The formulas have many conditions written into the equation just as mschoenheider described.



I know you would love to try and show that a dyno's readings are not accurate especially after May Madness and now the Texas dyno event but the truth is that they are a great measuring device. A dyno can give a constant reading with little to no variables due to the operator. This is not the case in racing or pulling.



On another note Merv's twins have been modified from when he got them from you... ... Because of his mechanical expertise is why his truck runs so well!



Doug

 

[Mark_Kendrick]

Merv Modified his twins with the turbo I sent him and thats all.



I have a degree in physics. I've learned a little.



if the dynos are off a bit I could care less on my truck. . 400+10% is still nothing to yell about. My 526hp 24 valve would be happy for it though



I was merely pointing out proof of what I've said all along. Dynojet dynos don't load the truck properly.



they are repeatable but wrong just the same.

 

[Jetpilot]

Dynojet dynos don't load the truck properly. they are repeatable but wrong just the same.

But you think an HP calcutator on the internet is a more accurate means of determining HP? Now as for Merv's twins..... I think he has done more than just change out a turbo. Merv has done a TON of tuning and modifications to get his truck where it is. Maybe more was done than one knows about



Doug

 

[Mark_Kendrick]

He's done a lot of tuning on the truck but the twins are untouched other than a turbo change and wastegate adjustments.



I'd be that he's had them painted or coated but no performance enhancing mods. . they're not needed. That setup works very well.

 

[MCummings]

Should we go into how much CFM our 359 C. I. Motors flow?



What do our motors flow at 3,000RPM and 0PSI boost (no vacuum, no boost), and what do they flow at 3,000RPM and 100PSI boost?



Merrick Cummings Jr

 

[Mark_Kendrick]

at the intake it's about 300cfm at 0, 100, 1000 etc. .



(359ci*(3000rpm/2rev)) * 1cft/12^3ci == 306. 31



at the air cleaner it's a different story. . roughly, 300+300cfm per 14psi of boost, assuming the aircleaner has no restriction.



the real way to measure flow is to compare mass/unit time.

 

[MCummings]

300cfm+300cfm @ 14PSI ?



300CFM @ 0 PSI

600CFM @ 14PSI?

900CFM @ 28PSI

1200CFM @ 42PSI

1500CFM @ 56PSI

1800CFM @ 70PSI

2100CFM @ 84PSI

2400CFM @ 98PSI

2700CFM @ 112PSI

3000CFM @ 126PSI



Is that correct?



So what does the Exhaust do? Is it the same? I think it flows more, because of the higher heat, yields greater volume.



Merrick Cummings Jr

 

[Proram]

Twins

Physic's, shmizics I don't know squat for Physics, i do know this my truck makes over 600 and Mr. Physics down there is luv'n his 400 hp. Merv made his great # w/ no help from your sorry Butt.

if your saying his truck was off by 50 hp on the dyno does that mean that Me, jet ,Sebek, Offshoreracer, snowman all get 50 hp to or is it just the truck w/ your setup on it? Stick the caclulater and internet in you pocket and pay attn. to the Dyno numbers, there the only thing that matter in this game! so why don't you go work on that tripple nightmare and keep your mouth shut till you got something to brag about. Any time you wanna come up this way theres about a dozen trucks just wait'n to Clean your clock!



And don't be Dodge'n behind any calculations

Or other mumbo jumbo that makes you feel important.



Scott

 

[esommer2500]

i do know this my truck makes over 600

580/1070 on 10/4/06

 

[Proram]

Twins

?? 2 can play this game, Why should i give my actual #?



Scott

 

[SmokinRam]

Re: Twins

Originally posted by Proram

if your saying his truck was off by 50 hp on the dyno does that mean that Me, jet ,Sebek, Offshoreracer, snowman all get 50 hp to or is it just the truck w/ your setup on it?

Oo.

 

[Mark_Kendrick]

Re: Twins

Originally posted by Proram

Physic's, shmizics I don't know squat for Physics, i do know this my truck makes over 600 and Mr. Physics down there is luv'n his 400 hp. Merv made his great # w/ no help from your sorry Butt.

if your saying his truck was off by 50 hp on the dyno does that mean that Me, jet ,Sebek, Offshoreracer, snowman all get 50 hp to or is it just the truck w/ your setup on it? Stick the caclulater and internet in you pocket and pay attn. to the Dyno numbers, there the only thing that matter in this game! so why don't you go work on that tripple nightmare and keep your mouth shut till you got something to brag about. Any time you wanna come up this way theres about a dozen trucks just wait'n to Clean your clock!



And don't be Dodge'n behind any calculations

Or other mumbo jumbo that makes you feel important.



Scott

You only get the 50hp if you have the ET to prove it.



There's nuthin to love about 400hp. I made a lot more than that with my 24V 14 months ago. You ever notice that a painter's house always needs painted? Well that's why my truck needs the TLC it doesn't get. It has the hardware to put out a lot more it just hasn't been properly tuned.



I'm still workin on the triples.



There's always somebody better and faster.

 

[Snow man]

I ran a 12. 26 with 7100 lbs and only 640HP,when I had a B1 on the truck. I ran a 12. 36 right before that run,and thats the last time I ran. Id like to get back to the track with twins,but the weather hasnt been very good here this yr it seems like it rains every weekend I have off. Mark ,since you believe the ET is more indicative of HP,what have your trucks run in the 1/4 mile?