JamesP

What has always bugged me about the flywheel vs. rear wheels debate is the claim that it is a PERCENTAGE. How can that be?

Why would the drive train absorb more hp as more is put in at the same speed? I lean more towards a flat (SLIGHLY inclined as hp increases) rate of loss. ex. A 6-speed w/ 11.5 rear takes X hp to turn 55mph......

BTW- I sure as heck don't trust a manufactures rating is what actually makes it to the flywheel. DC could easily fudging in either direction. Not to mention how different these trucks run, and mpg is a whole nother story.

Steve-l

Richard,
You are exactly correct. I do not understand what these boxes exactly do and unless you have access to the source code, neither do you and there is my point. This compound effect could be damaging just as easily as it might be beneficial. When I read the Banks warranty, it clearly states that they could not be held liable for using their equipment in any other manner than that expressly written. Maybe the other responders could check their warranty and reply.
Steve

Steve-l

Tom,
Yes, it does. The law states that in a power system, power applied must equal work out and any difference equates to heat. That means that all work losses always translate to heat. I didnt make this up. Read the first and second law of thermo dynamics yourself.
Steve

Steve-l

James,
Your point is well taken. We have been exposed to comments like "It is a proven fact" or "It is well understood in the industry" all of which is misleading. In a perfect world we would like to think that all dynos are the same, they are not. This is my experience. It is not second hand. There are big differences from one machine environment and another. I have done chassis tests and I have done engine dyno runs, but I have never done both on either the same engine/truck or on the same dyno. I submit that if you are not in control of both tests objectively any statement on the percentage of loss is a wild assed guess. What I know for sure is the temperature rise of any of my driveline components is next to negligable on any vehicle I ever worked on. I also have to acknowedge that it is next to impossible to execute the loss test in real life. It would have to be done on a chassis dyno. It would have to run for at least an hour and the likelyhood that the rear tires would survive for an hour is pretty slim. At the end of the hour test, temperatures could be recorded and compared to temperatures at the start of the test. The thermal mass of each component could be calculated as well as rate of heat radiation for each component. Once these are known, the rate of work absorbtion would be known for each driveline component. At the end of the day all the inefficiency would most likely reside in the now smoking tires with marginal temperature rises elsewhere. That's my guess.
Steve

AK RAM

So who is going to be the first one to buy this xcellerator and give us a report?

CTDHokie

I'd just like to see a dyno chart....I can't undersatnd how they can claim 270hp without a dynochart to back it up....if they are claiming 270hp at the flywheel show me an engine dyno chart.

Gypsyman

This theory has bothered me every since I was just a kid starting out. I've argued this point with so many people over the years that I've lost count and never have heard a theory that makes any sense. It just seems to be a general guideline for laymen such as myself. I've stopped even considering fw hp. If it isn't hitting the ground it doesn't exist as far as I'm concerned. One nice thing for the guys with hand shakers is I believe we get more to the ground due to the use of gears vs clutches. Just my opinion, YMMV and batteries not included.

Steve-l,

As far as not knowing the source code you are absolutely correct. I have no real idea of how the code actually works and don't claim to. I do however understand how they function in theory and what parameter they claim to affect. I also believe that a duration box stacked with pressure box has a compound effect. More fuel delivered over an extended duration equals a higher volume of fuel delivered hence the compounded affects. After rereading all of your post it seems to me that you are speaking of stacking two boxes that affect the same parameters. Is this correct? I definately agree that stacking can be damaging as well as benificial. In my opinion any increase in hp is shortening the life of your engine due to increased wear at the very least.

Richard

bigblock2stroke

I agree with the point that you should be able to do all the mods with one box rail pressure, injector duration, and injection timing.

Stacking in principle is a tad ridiculous.

You have to add a duration box because your pressure box doesn't have the software/code/etc. to modify the timing?

If that is the case, you should have bought a different box.

Tom488

If you can show me a box that alters fuel pressure, timing, and pulse width, and provides on-the-fly adjustability for any, or all three, I'll be happy to toss my current combination and run right out and buy it.

Unfortunately, none exist at the moment.

banshee

HP junkies such as myself resort to stacking these boxes because, at this point, it's the only way to make big power. If you want to squeeze every bit that the fuel rail in our motors can offer then you have to run more than one box. There is nothing on the market right now that will single handedly give the power that two put together will. Until someone markets a pressure/timing/duration box that pushes that edge, it's going to be stacking that makes the big numbers.

As for the power loss issue, it's always been my opinion that driveline loss is comprised of a fixed amount of HP loss (due to overcome bearing friction, inertia, drag, rolling resistance, etc.) combined with a much smaller percentage of your rear wheel HP. For example, if a 305 HP truck dynos 244 rear wheel horsepower it has lost 61 HP from the flywheel to the pavement (assuming it really had 305 at the flywheel!!). Most guys will say that the driveline sapped 20%.... fair enough. However, if the motor is ramped up to 500HP, I don't buy the argument that the same driveline is now losing 100HP (20% of 500). IMO it is more like 40HP constant plus a smaller percentage.... 7% for this argument. There shouldn't be any more bearing drag or rolling resistance no matter how much power you have, but gears lose more (thru heat!) the more power you put through them. Like Richard said, though, I really only worry about RWHP numbers anyway... and real world performance .

Tom488

Steve,
You're still ignoring the fact that it takes energy to turn the 300+lbs. of drivetrain (all that "stuff" between the flywheel and the tires). I'm not talking about the heat produced from the friction of metal-on-metal, or metal-on-oil... I'm talking about the kinetic energy imparted into the drivetrain components. They have mass, so therefore they're consuming energy when put, and kept, in motion.

Again - this is all theory, and fairly meaningless. If your "theory" of only a 5% loss is correct, your 305HP truck should dyno at 290HP. Go down to a chassis dyno and prove your theory.

slimpicken

Yes Work "lost" translates to heat, however you are only losing a percentage of the work is what these guys are trying to point out. They just didn't know it Not all the work from the feul burning translates into direct heat. I'm just finishing a physics class in college.

Fummins

My stacking of the RAMifier and Bullydog Power Pup DOES produce substantial gains over running one of them solo.The dyno shows it and so does the seat o' the pants meter.

AK RAM

I know you don't think your going to get away scott-free with a comment like that. Sounds like someone is holding out on some dyno results.