RWHP Guestimations...
11-30-2006, 01:48 AM
#31
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11-30-2006, 01:50 AM
#32
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I wonder how much your auto is losing though. I would have thought you were well over 700...Well, I guess not having the Smarty leaves 195HP off which is HUGE at these levels.
11-30-2006, 03:02 AM
#33
RWHP was one reason to go with a super single since it would weigh less than two stock dually wheels and tires; however, on a dyno, I wouldn't think that the wheels would make much difference since you have so much less resistance from the rollers as opposed to asphalt. You wouldn't think the weight would play nearly the factor it would on the street.
I believe there are some dyno's where you take your wheels off and some mechanism is placed on your rotor or something for a more accurate measurement.
11-30-2006, 08:05 AM
#34
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What do you guys (who have dyno esperience, since I have ZERO) think I will ultimately end up with on the dyno when all is dialed in correctly. Within two weeks I will have the Flux 3 Hellfires, my TST with adjustable timing, my Smarty is already on #9, and my Stage 3 H20/Meth Kit from Snow. That along with all my other mods you would think would put me right in the ball park of 850-1000HP, wouldn't you think??
11-30-2006, 08:20 AM
#35
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D.Wiggs, With your tire set up you will never get the numbers on the dyno that the truck will do on the street. At the track I can spin the tires in 4wd on every shift and max out boost well over 80psi and still be running less than 1450 with the water cranking. On the dyno, My boost record is 44psi for 550hp at 1500+egt. Duallies have a hard time sticking to the rollers with the less psi ground force. I've resigned myself to building an engine and engine dynoing it before it goes in the truck.
If you can't get the power to the ground (like me) in the 1/4 mile than you will have a very hard time getting it through metal rollers. Put 2000lbs in the back, deflate the tires to strap down and then inflate to a moderate pressure.
If you are building boost while dynoing and then the boost drops ... it is because the tires are slipping. Once you hit 20psi you should be able to take boost to the limit if traction holds. Good luck, ks
Oh Yeah....710hp
If you can't get the power to the ground (like me) in the 1/4 mile than you will have a very hard time getting it through metal rollers. Put 2000lbs in the back, deflate the tires to strap down and then inflate to a moderate pressure.
If you are building boost while dynoing and then the boost drops ... it is because the tires are slipping. Once you hit 20psi you should be able to take boost to the limit if traction holds. Good luck, ks
Oh Yeah....710hp
11-30-2006, 08:54 AM
#36
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Well when i was at ATS the most they ever got any truck of theirs to make with their turbos was 690 on fuel alone. They said that their turbos just dont flow enough air. Thats why they are coming out with a new set of turbos that will make over 700 hp. Unless you got the "magical set" that produces more then everyone elses then you dont have enough turbo to make 1000 hp. I dont think a lot of guys realize what it takes to put 1000hp to the ground. Not only that from what ive seen for my modded cp3, Id need a dual cp3 to make 1000, as a modded cp3 just not gonna cut it looking at the fuel rail pressure im seeing. Maybe at the flywheel youll see 1000 but i like to see mine at the ground.
11-30-2006, 08:57 AM
#37
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That's HUGE at any level!
11-30-2006, 09:23 AM
#38
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How do u figure not having the smarty is loosing me 195 hp at the ground? My xcelerator isnt giving me anything? Sorry i disagree. Im not saying the smarty isnt a better stack with the tst, but i doubt im loosing 195 hp just by not having the smarty. IMO
11-30-2006, 09:27 AM
#39
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It doesn't matter what surface you are on. Lets call your wheel a disk. It is all about the radius of the center of mass. The larger the rims, the greater the radius of the center of mass, and the more energy it takes to rotate the disk or wheel. For example, say we have two disks made of steel 1 inch thick and 20 inches in diameter. One disk is solid steel. The other one has the center (maybe 16 inches diameter) cut out leaving 2 inches around the outside. The solid steel disk takes less energy to rotate!
Since the issue is RWHP, which infers straight-line acceleration, I'll disregard unsprung weight-related handling.
Tire & wheel choices affect acceleration in 4 ways: their effect on drive ratio, how much traction they have, how heavy they are as part of the total vehicle weight, and how difficult it is for them to be rotationally accelerated. All else being equal, lighter rolling stock will allow faster acceleration, but where the mass of the tire/wheel combo is in relation to it's axis of rotation is what determines it's resistance to acceleration. The further the mass is away from the axis of rotation, the harder it is to accelerate (more potential inertia to overcome). Of course, in your example, one disc weighs more, so it'd be harder to accelerate.
An interesting example: 20" alloy rims with low-profile rubber, say 45 series, and 16" alloy rims with 75 series tall sidewalls.... which one will take less energy to rotationally accelerate? The answer may surprise you.
Sorry for the long post - not enough coffee to be succint yet
11-30-2006, 10:38 AM
#40
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11-30-2006, 10:40 AM
#41
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I have no dyno exp, but what ive read, but Id put the stock tires back on to dyno, and leave the outside duals off, if its true that they may break lose on the dyno.
1300 hp and 2550 ft/lbs
1300 hp and 2550 ft/lbs
