Who’s industry standard? Standard for what? Do any of the major car manufactures test their engines on Dynojets? Ever seen an Engine Masters Challenge use a Dynojet? A chassis dyno is a tuning tool. It’s not designed to give real world accurate HP figures. If you can’t understand that…I’m not surprised. Sit down before you hurt yourself.

I wasn’t aware I was nearly run out of Yellow Bullet? I may have disagreed with some folks about as clever as you… but I sure wasn’t run out of anywhere. I’ve been put in my place several times in every forum. I’m ok with that, I even encourage it. I’m just muddling through this stuff like everybody else and make TONS of mistakes. I’m a big enough boy to admit when I’m wrong though. And if I see someone claiming impossible power figures, I’ll call them out on it. And I'll try to nicely explain why I think they are wrong too...

All of your posts lack substance. There is no factual information or data. All we get back form you is “the dyno said”. Explain to me in your own words how you think your results are possible without the word dyno. Pour some of that superior knowledge out for us, I’m dying to hear it! I think you should go more into your intake manifold restriction and VE theory… It’s always good for a laugh. Or how your 3200lb rx7 will take flight without a 200lb passenger…

Lastly… did you just criticize my house? really? I think you know about as much about my house as you do about turbo systems and how they work. I don’t see how the amount of fun you had, house size , how “HARD” the 1500 miles were, or how much it cost is relevant to the thread topic?

 

I am 100% OK with that. I don't have anything to prove to anyone. You don't like it? Deal with it! Nothing was manipulated with my runs, it made what it made. Considering the last car I put together made 640whp, and went 9.5@151, I trust its measurement of horsepower.



8.7@161? LOL. Sounds like its working well to me. I am ok with people who want to have constructive criticism, but you post BS just to stir the pot. I have no time for you.


I have been involved in tuning around the country since 2004. The vast majority of shops I have worked with use DynoJets. In my opinion, the majority of people in this community feel the Dynojet is the standard that other dyno's are compared to. There are even to local shops that operate a superflow and Mustang dynos respectively consider the Dynojet the industry standard. Maybe its because they have been around the longest? Maybe its because they have the most units in operation int he performance industry? Maybe its because they seem to be the most repeatable? Whatever it is, this is the sentiment that I have observed in the past 11 years of working in this industry.

Also, I am happy to have a constructive discussion with someone whom is willing to listen, but you are not. You think this equation you pulled directly out of your *** is law, and that's it. There is no reasoning with you.


Simply put a turbo charged engine running over 100% VE will gain power at a rate faster than your equation allows as KPA rises because your equation ASSUMES 100% VE!!!

1) You have admitted that higher than 100% VE is possible (in reality, a modern turbocharged engine operates well north of 100% VE-any idiot with Google can finf this info)

2)You have also stated that your equation assumes 100% VE is best. THIS is the issue with your math, and you just cant see it!



I tell you what. I have provided actual math showing how VE in a turbocharged system can achieve over 100% VE, and provided links to automotive textbooks explain why and how. I have provided multiple examples of cars producing such output.

I will be HAPPY to drop all of this, and say I am wrong if you can find one, just one, credible piece of automotive literature that suggest engine output at 1 atmosphere will be half of that output at 2 atmosphere and can not be higher....




Between 04 and 2010, I likely sold over 1000 turbochargers and related system components as well as developed and designed some of the highest qualify fully encompassing systems on the market with Ron during my time at http://www.shearerfabrications.com/. I have also been all over the damn country sole for the purpose of tuning turbocharged cars. I am going to go on a limb in saying I know more than the average idiot on LS1 tech, and unless you have similar real world experience, I may know more then you, chief.

As for your house, easy was to prove me wrong...post a current pic! (with the car in the garage for proof preferably) I will admit I may be wrong here as well, you may very well live in the Taj Mahal.

 

If you had nothing to prove, then why the hell start a huge debate? And if you're as great of a tuner as you claim to be, then you knew damn well that it would indeed create said debate. You are claiming to have the highest horsepower'd 5.7 liter LS1 known to man. Until that dyno sheet gets backed up on the track... it never should have been posted. I mean, you had to have known people would have wanted to see some track numbers to back it up.

Maybe it's just me, but it sure seems bothersome that a world class tuner wouldn't datalog his own dyno or track runs. That just boggles my mind. I know... you don't care... but every tuner I know, especially those that do it professionally; they ALWAYS log the runs that are being made. ESPECIALLY if it's their own vehicle.

 

Just as an outsider with zero knowledge to make me dangerous in any type of intelligent argument to speculate on any of this.


Seems that you should maybe be happy in your results quietly and not post threads with "records" and outlandish seeming numbers etc, if you don't intend to honestly defend legitimacy.


Seems like you not recognizing any "DYNO" as purely a tool... just adds to the overall ignorance being brought to light with facts. Not trying to be another A*hole in this thread, just stating my opinion on why it has turned into what it has.



Sitting back to eat popcorn now.

 

You are literally a f*cking child. An arrogant little ***** of a immature child. I read this thread just to get a kick out of how blatantly ignorant you are. Your motor does not bend the laws of physics. Get that through your head. Its very simple, you just refuse to see it, and CLEARLY don't understand it. Therefor you argue. But continue.. bc you will

 

How did his house get brought up in this and WTF does it have to do to prove your dyno numbers. Read up on some gas laws and you will see why and where he is getting his arguments and math from. What he is saying is 100% correct and has been proven in labs with 100% control long before any of us were born. I don't care if you designed, built and tuned a car for God, you can't break those laws. I also don't believe you made up these dyno numbers either. What I do believe in is proof, it's in the mph.

 

I just can't believe he built a car to make a dyno number and not actually go fast. I thought we were all here to learn how to go fast and not just make banzai dyno runs to hang our hats on.

 

I am dying over here!

 

I didn't start this debate! LOL. Now that really would not make sense.

A chassis dyno is a tool, so is an engine dyno. Accuracy of both can be questioned, so does that make both illegitimate? Weather it rubs people the right way or not, my pile put down more power than anything else powered by a stock LS1 according to this forums and I'm sure countless hours of hater research.

I never "claimed" outlandish numbers-I simply posted what the car made @21+psi. That's it.


If likely building, selling, and tuning more turbocharged cars than anyone in this thread makes me ignorant, then ignorant I am.

Speaking of ignorant-Please, post the law of physics I am bending. As I told forced, I would be happy to admit fault if something was provided that was actual "math" from a physics, or automotive engine or theory text book-not out of someone's ***.

I had a friend from a shop down south call me about this for a good laugh (also a dynojet owner and operator) and the question was asked "I wonder what this guys house/life looks like. Its got to be sad!" . A picture of an odd guy in a shack in the middle of a corn field somewhere wearing a tinfoil hat came to mind.......I just wanted to see if he was right.

What would you expect the car to trap-seeing 8psi in 1, and, and 3rd gear...and 15psi in 4th, and half of fifth? (completely fell out of boost on the 4-5 shift). I think 10.5@146 is about right under those circumstances, no?


Again, the car was built to see what I could do with a stock Ls1 on a shoe string budget. I most enjoy 1/2 and 1 Mile racing, and Roll racing with the occasional trip to Mid Ohio or Nelsons ledges. For that reason, I kept it an M6. I intentionally built the turbo set up to have a late torque peek to have a chance to keep the motor together int he 7-800whp range. So far, so good.

As mentioned above, the car went 10.5@146 on a 90 deg. and 70% humidity day on what I would consider a half pass boost wise. You don't consider that "fast", well you have that right. Fast is a very relative term!

 

Coltboostin...

Ok... I swore I wasn't going to jump into the middle of this with both feet, because it takes up time I could most likely put to better use in other places...

But there is a LOT of misinformation in here, thrown amongst a few nuggets of truth.

Time to get some "math" involved along with some common (or maybe not so common) sense and a little physics...

What was the rpm and bsfc. of the engine at it's 852hp max ?

We can start there...

 

Among other things I'm still waiting to hear why you think a 6spd is faster than an automatic In roll racing.

 

Well ok...

Since it might take coltboostin a bit to come up with the numbers we need, I will use some that should be close but tweeked more in his favor than what the real ones most likely are.

First things first.

I REALY hate doing math and hate writing/typing even more...

So I hope at least a few appreciate the effort spent...lol

So school is now in session...

I am going to use this site and in particular this page as it will help in maybe making some of these things a little more clear...

http://www.epi-eng.com/piston_engine...efficiency.htm


(It is a great site that has a lot of good info and equations to use and evaluate...So break out your calculators dive into it and maybe learn a few new things)

Ok...On to some numbers.

To quote from the above page...

"In a four-stroke naturally aspirated engine, the theoretical maximum volume of air that each cylinder can ingest during the intake cycle is equal to the swept volume of that cylinder (0.7854 x bore x bore x stroke).

Since each cylinder has one intake stroke every two revolutions of the crankshaft, then the theoretical maximum volume of air it can ingest during each rotation of the crankshaft is equal to one-half its displacement. The actual amount of air the engine ingests compared to the theoretical maximum is called volumetric efficiency (VE). An engine operating at 100% VE is ingesting its total displacement every two crankshaft revolutions."

"For contemporary naturally-aspirated, two-valve-per-cylinder, pushrod-engine technology, a VE over 95% is excellent, and 100% is achievable, but quite difficult. Only the best of the best can reach 110%, and that is by means of extremely specialized development of the complex system comprised of the intake passages, combustion chambers, exhaust passages and valve system components.

The practical limit for normally-aspirated engines, typically DOHC layout with four or more valves per cylinder, is about 115%, which can only be achieved under the most highly-developed conditions, with precise intake and exhaust passage tuning."

For a known engine displacement and RPM, you can calculate the engine airflow at 100% VE, in sea-level-standard-day cubic feet per minute (scfm) as follows:

100% VE AIRFLOW (scfm) = DISPLACEMENT (ci) x RPM / 3456


So a LS1 is 346 ci. in displacement.

We will use 7000 rpm until we get some "real" numbers.

346x7000/3456 = 700.81 scfm

So 700 scfm is the 100% VE airflow of a LS1 at 7000rpm at 1 atmosphere (14.7 psi) (Which would be "zero" boost)

Ok...Onward and upward.

In keeping with giving his engine the benefit of the doubt...

We will say he only had 10% drive train loss on his 852hp run.

10% loss would give us a extra 85hp added to his 852 which gives us a total of 937 crankshaft hp.

We will round it up to 940hp to make the math a little easier.

Until he gets us a BSFC number we will assume a reasonable BSFC of someplace between .450 and .500...

Will split the difference and call it .475 which again is giving him a better number than it most likely is.

Ok...

Armed with these numbers it's time to do a little more "number crunching"...

We will use this equation from the same page we have been using to figure out what coltboostin's VE is on his engine.

The equation is this...

REQUIRED VE = ( 9411 x HP x BSFC ) / (DISPLACEMENT x RPM)

So...Lets plug some numbers in...

9411x940hpx.475bsfc/346ci./7000rpm = 1.73 or 173% VE

So coltboostins engine has to be at 173% VE to make his claimed hp number.

Which if you divide 173 by 21 (the pounds boost claimed) you get 8.24.

Times it by 14.7 (14.7 psi boost) and you get 121% VE which there is no way in hell you could get...



So...Lets try and clear the "air" some...

Coltboostin is right when he says that "adding boost" increases the VE of a engine.

Forcefeed86 is also more or less right as he was saying that the "density" in the cylinders was increased which is a round about way of saying the VE increased.

They are one and the same...To increase the VE of a engine you have to increase the "density" of the charge (Airflow) into the cylinder...It's the only way...Whether or not it is done by "boost", N20, cam,intake and exhaust passage tuning or lower air temp etc.

Now where Forcefeed86 is more or less right...Is in the statement that you can not more than double the horsepower of a engine at 14.7 psi boost..

It's past my bedtime and I am more than tired of typing...

So...Maybe we can tackle that another time.

 

Bazinga lol

 

so for his claims and boost/7k rpms, 121% VE would have to be achieved? which with a bone stock ls1 isnt even nearly possible correct?

 

Just some food for thought, not saying that I believe it to be the case, but its just one possible explination. I appreciate the basic physics of not being able to more than double power with 1 bar of boost, but there are other factors that come into play. A stock motor with a stock cam and two fairly big turbos ("big" being a subjective thing, but work with me here for a second), may create a condition by which exhaust manifold pressure is lower than intake by several psi. This can artificially raise the base VE. Typically it's something you'd only see on well thought out engines, with carefully ported heads, cam selection and big long tube, merge collectors turbo manifolds, but it MAY be playing a role here too.

The first car that comes to mind for me was a supra that was making 24psi intake, 18psi exhaust back pressure. In all honesty I dont remember the exact setup, but I recall there not being any fancy race tech in it, just a well thought out street car.

Applying that to the situation here, it wouldn't take a great deal of difference in pressure to make all the numbers start to work. 120% VE NA would be quite easy to achieve in the 'real world' with just a few psi more in the intake versus exhaust. (Yes, I realize just how ridiculous that sounds)

I really do love the budget builds on here, and appreciate the time people like coltboostin put into show casing there work on here for people like me to read (denmah especially, guy's a ******* legend), maybe this has made me biased, but in general I like to assume the best in people.

 

No...Like I wrote...

Taking his 852 rwhp figure which was at 21psi boost and adding 10% for drive train loss we come up with a number close to 940hp, which when we use the equation, we come up with 173% ve...

The 121% ve number is what it would be at 14.7psi, which is the boost that in a perfect world should double the n/a hp number.

The "real" world fact is that none of his numbers or the ones I have posted are in a "perfect" world.

Way to many variables and assumptions etc, for it to ever be.

In my numbers I have had to assume (remember it means ***-u-me lol. ) what his drive train loss might be, the rpm his motor made max hp at and what the bsfc of his engine could be, which all if different can change the ve number.

I have tried to use numbers in his favor when calculating his motors VE.

Now I want to be clear on some things....

In NO way, do I think coltboostin changed, cheated, lied about or inflated the dyno numbers on his engine...

I believe that on that day, with that car, with those "correction" factors" on that dyno those are the numbers it spit out...

Do I believe them to be a "true" reflection of what his engine output is...

Well that is the rub.

A chassis dyno can NEVER give you a true indication of what your "true" engine horsepower is because there are way to many variables which can effect it, and with most of them there is no "easy" way to know just how much it may have effected them.

Most have to do with drive train loss etc.

Things like rotating mass...

Things like...Flywheel, clutch, convertor, transmission, drive shaft, axles, wheels/tires etc.

Other things that can effect drive train loss through drag/friction/tire slippage etc...

Like...Trans type/style, rear end type ie: 9" ford/8.8 etc., IRS or straight axles, even gear lube weight/type.

Plus a whole heap of other things...

You could have put his engine in a different chassis with a different drive train on that same day and it would have put up different numbers unless the drive train loss was exactly the same.

And that is the problem...

There is not a easy way to know just what those losses might be for us to get a accurate number on what the engine is really putting out.

So what is a chassis dyno...

It is just a tool...

It wasn't made for people to "set records" on, as there are WAY to many variables in it's possible numbers, do to differences in dyno's, the people operating them, and all the above mentioned items, not to mention any kind of "rules" for the making of a "record", for it to ever be accurate enough in that type of use.

It is outside the perimeter of what it was made for...

But people tending to being a competitive lot they are...

We will always have some kind of a "Top Dog" list...

 

Maybe some day we can come back and "explore" that "theory" but right now I am burnt out on typing...lol

(I really do hate to write/type... Figure it must be some deep rooted rebellion against the time I spent in school...lol)

As far as your last paragraph...

I could not agree more...

I appreciate cooltboostin, forcedfed86, denmah and everybody else that has taken their time to post their builds on the forum...

It is one of the things that make this sight great...Especially the Forced Induction part.

Being a more with less type of guy, I also love the budget builds/ideas etc.

There are few things more enjoyable to me than building/racing something that kicks *** on someones high dollar toy...

Slaps a big grin on my face every time...

In closing...I have no "beef" with any of the posters on this thread...

I think coltboostin has built a righteous low buck machine as well has forcefeed86 and others...

I think what got stuck in some people "craw" was colts dyno hp record numbers...

Which in the end is pretty much pointless to argue over since there is no way to truly know the exact hp his engine is putting out short of throwing it on a engine dyno.


Oh...One other thing in coltboostins defense...

I really don't think the day he took it to the track he was going there to "back up" any dyno numbers...

I think it was more of a...Lets grab my buddy and hit the track and see what it will do type of deal.

No real plan, other than to gets some runs in after spending a lot of time, sweat and money on it.

It was simply...

Playtime.

 

Again I ask… The industry standard for what? For a tuning chassis dyno? Sure I’ll agree with that. It’s NOT the industry standard for accurate HP figures. Which is why it isn't used when accurate numbers are desired.


You claim you want to have a "constructive discussion", yet you bring up points like... "How big is your house?" and "I've sold a 1000 turbos". How are any of these things relevant? Your counter points have consisted of links to subjects you don't understand. As well as links to other dynojet examples? How is that intelligent debate?

If your paid to travel around the world and tune turbo engines, why are you not tuning you own car? Why do you not data log? Why do your welds look like hammered dog poo if your a an accomplished designer/fabricator?

Actually, nevermind all that. It's not relevant, and I don't care.


Simply put, your wrong.

1.) That's not how it works read a book. And what math have you provided?

2.) VE is relative to atmosphere and based on density. (which I have said many times and you still can't grasp).

Think of it in terms of volume VS pressure.

At sea level... 2.0 liter 4 stroke engine.

Every 2 revolutions it will displace 2 liters of volume at 100% VE, yes? We will say the engine makes 100HP per liter to make things easy. So 100% VE would be 200hp.

But your 2 liter is a tired bone stock 2 valve engine and it's only achieving 85% VE. So it's only pumping out 1.7 liters of volume or 170hp. The volume displaced is a physical/mechanical limitation and cannot be changed with boost. even at 200psi it will still only displace 1.7 liters. Changes made to the ports/heads/cam/intake/headers etc are the only things that can change volume output.

Along comes Mr. Turbo. (Again we have to assume a 100% efficient turbo system with no losses here to avoid air density math.)

Mr turbo can only add pressure... Not volume. So when Mr. turbo doubles the pressure the 1.7 liters displaced remains the same and the HP produced doubles to 340 hp.

For your claims to be true, the engine would have to gain volume/mass with added boost. Which is impossible. This is where the formula that you claim I made up comes from. Which as I said... if you looked around even a little you would see the formula is common knowledge and used everywhere.

Like this simple calculator. Which is merely doubling the HP value input per 14.7 PSI. This of course does not calculate turbo system efficiency which is based on temperature/pressure... aka density. So real world numbers MUST be lower than this.

http://www.wallaceracing.com/hp-blower.php


I posted links to several turbocharging books. All of them mention doubling HP if density is doubled in some form or another, then subtracting efficiency losses. They like to use SCFM and pressure ratios, but it's the exact same thing.

Richard Holdener-Dyno proven small block ford performance Pg.85






I refuse on general principal. I'm sure there a few pics in my build thread if your that interested.

 

Most don't grasp an engine is a positive displacement pump and what this implies

Also VE mirrors the TQ curve for the most part. As peak tq is also the most fuel (and air) consumed per cycle

 

You have hit it on the nail on both statements...