You would never think of those numbers if you just looked at it, Bad Ass Car :thumbsup:

Mark,
Are you running solid motor mounts with this motor?

Looking great Mark. I always appreciate your desire to keep things servicable, yet sanitary. Kick some ass, we are all rooting for you.

Looks OEM under the hood.:thumbsup:

:wow: Wow you guys are kicking some major butt on putting it together :thumbsup:

Sooooo how long before you have ignition??? You really can see you that you work for GM in how it looks like GM built it just looks so factory! Great job Mark:bow:

Oh yah and no pressure only 58 days until the start of Sema :willy: :rofl:
Sorry couldn't resist! :thumbsup:

THIS THINGS ROCKS!!!

Remember when "bling" was the thing? Sorry, it wasn't for me either.

THIS CAR TAKES THE CAKE!!! And the whole barbeque too....

Mark you make this look easy ... LS9 power is amazing!
Thanks for sharing ... could stare at these pictures for days and still be amazed at the detail.:cheers:

Is that wiper motor going on the inside of the cowl? That's cool ... kit or homemade?

"If you can make black marks on a straight from the time you turn out of a corner until the braking point of the next turn, then you have enough horsepower." Mark Donahue


:rofl: :willy:

We get lots of dark marks on the pavement out here too...:(

http://i87.photobucket.com/albums/k1...azz/amish2.jpg

lol

Sorry guys, I'm not into all that racing stuff, but I do know a beautifully, well done car when I see one and this is at the front of the pack. :hail: :hail: Very nicely done as all of your cars are Mark. :yes: :yes: Although, like I just said I'm not much into racing, I do like to know when a car does well and is a top performer. Can't wait to see what how it does and how much ass it's gonna kick. :thumbsup: :thumbsup:

Just read the entire thread. Awesome build and great ideas/details for the rest of us to emulate.

Kerry

Very Impressive.

The dyno figures, the paint job and the OEM feel under the hood. :wow:

Mr Stielow
 

Ahhhhh Mr Stielow, Friekin soooo sweet, Congrats:bow: This thing is sick, liking the colors and no bling approach, very impressive,:thumbsup: :cheers:

Some more pics...

http://i1158.photobucket.com/albums/...hem_engine.jpg


http://i1158.photobucket.com/albums/...ayhem_hood.jpg

yeah, at least he got away from the red/blue fittings. :lol: Just kidding Mark. :lolhit:

Thats it ? Two pics ?

Two pic's.Two:thumbsup: :thumbsup:

Haha... Guess you need to bug Stielow to get more work done :D

Would sure like to hear as many details on the engine as you want to share.
All I know is that it is a "ZR1" supercharged 427 LS.

Heads ? Cam ? Idle vacuum ? Compression ?
Mods ?

I usually assume that even the modern compression style blowers are still only about 5% efficient (including drive losses), which means at 882 whp the base engine is making 550 to the wheels ?

Huh???!!!!!! I will guarantee it makes way more than 550 rwhp. :thumbsup: 5% efficiency seems just a bit low................ ;) I remember when they were first starting the dynoing of the ZR1's their first dyno pulls were making close to 700 rwhp. They definitely backed it down for the production cars.

Well if it is more efficient than 5% than the base engine power number is lower than 550. I know you understand that - IF the blower is 6% efficient than the base motor would make 512 whp. This assumes 12 psi of boost.

550whp is about the max I've seen for the 427Ls motors that are in what I would call the "streetable envelope", and Mark has always setup his cars to have reasonably tractable drivetrains. So I don't think it is "under rating" it to arrive at 550, that is a huge number, somewhere north of 650 on the motor dyno. That's why I'm always very curious about idle speed and vacuum, its the only way I know of to get some idea of how aggressive the engine is.

Not trying to be "one of those guys", I'm just genuinely curious about what went into such an amazing engine.

I think you and I have a different definition of efficiency. If I say a blower is 5% efficient then that means it's 95% inefficient, it costs nearly as much HP to run as it makes.

Since the stock ZR1's dyno in the 540-550 rwhp range (Dynojet) and make 638 flywheel HP, I'm not sure how you'd add 240+ flywheel HP and still dyno at 550 rwhp.

Yes, the blower costs HP to run. If he's making 880 HP he's probably using fuel for 1000 HP+ to cover running the blower.

To answer your question on engine specifics, we'll wait on Mark. I do know that Red Devil idled like a stocker at 600-650 rpm, so the cam doesn't have a lot of overlap.............. ;)

Yeah my mistake - I'm totally using the phrase "blower efficieny" incorrectly. By that I mean you gain 5% power per psi of boost. The max "efficiency" possible is 7% (100 % / 14.7) which is close to what turbos get. Blowers (especially PD style) usually dip down to 5% per psi of boost.

When I say the "base engine makes 550whp" I mean with (theoretically) no boost or blower restriction the base engine makes 550

I was under the impression those dyno results I saw were chassis numbers, but I went back and those are engine dyno numbers. So if I run my little rule of thumb -
5% * 12 psi = 60% more power

875/1.6=550 base engine power at the flywheel. That actually makes more sense to me as a 550 hp Ls 427 is well within a streetable, tractable envelope.

Either way a tour de force, especially as we know the work has been done so it can live under track abuse.

Now I understand. :thumbsup: 550 n/a FHP is probably close, knowing his conservative boost level. Hopefully Mark can share the engine specifics that aren't secret. :unibrow:

After beating mercilessly on Red Devil for a couple years without issue, Mark was almost set to have Brian Thomson (http://www.thomsonautomotive.com) just build another copy of that engine - after all, why mess with a proven package? However, we were always talking about how he could use more HP, while giving up some TQ. As well, the thermal requirements for Red Devil were getting a little difficult to say the least.

The goal of engine for Mayhem was to address all of these 'short comings' - and I think the results show at least a couple of those have been meet very well (won't know the whole cooling factor until installed and run in car).

As far as calculating power per % boost - it gets a little more complicated. Positive displacement superchargers like the TVS Eaton series are quite efficient from an adiabatic standpoint. But like any compressor, they have an efficiency map that shows where you are operating based on total airflow and pressure ratio. Adiabatic efficiency determines how much you will heat the air for those given parameters (airflow & pressure ratio). This factors into a couple parameters you are most interested in: Density ratio and temperature.

While everyone running a boosted motor likes to talk pressure ratio (PSIG), what you really care about is density ratio. That determines the amount of oxygen you are moving through the engine (and therefore power). The more efficient the compressor, the less heat added for same amount of pressure (which results in higher density ratio).

As well, less heat means less heat to remove with intercooler. If you had 100% adiabatic efficient compressor, you'd need no intercooler as outlet air would be same temp as inlet air (and density ratio would be same as pressure ratio).

Added to this, with an engine driven compressor, there are mechanical power losses associated with powering the compressor. Again, these are plotted out on an efficiency table, but one that relates pressure ratio and compressor RPM to power required. (Turbo's have losses too (backpressure - just not directly mechanical - there is no free lunch....)

So what does this all mean when we designed Mark's new engine? Well, we knew the goals (more HP, less TQ, less heat). And we had all the data from Red Devil. So we targeted efficiency improvements to reach these goals.

Adiabatic efficiency was plotted for desired airflow (@ density ratio) to increase power and calculate intercooler demands. Blower losses were plotted to calculate mechanical efficiency. Airflow of engine was altered with revised cylinder heads and cam shaft design based on modeling.

Original target for Mayhem engine was a conservative 850 HP / 800 TQ while reducing cooling demands. Result was we overachieved our goals from the power side - and data from engine dyno shows we are on right track from cooling side.

Red Devil made 780 HP / 830 TQ @ 15 PSIG in final calibration form.
Mayhem is making 875 HP / 815 TQ @ 11 PSIG (and we're not done yet!)

My old thermodynamics instructor would be proud! Actually still using that knowledge....

Bottom line, with all the parameters involved, it is never as simple as using a fixed percentage increase per measure of boost. Many, many pages of notes and calculations for all this - just scratching the surface.

Great Read! I haven't heard "adiabatic" in awhile! I really miss Thermo. I remember all of those assumptions we made -- - lots of 100% adiabatic compressors in those old homework problems.

This level of engineering and preparation is what makes Mark's cars special. - - they are true representations of the Scientific Method

Plan
Do
Check
Act


Can't wait for this project to reach the first iteration of "Act".

thanks for the info Dave. I understood most of it......... :lol:

Are you coming out for Optima?

Yup - I'll be there! Always a good time to catch up with people and see some awesome cars.

Perfect! You can be the guy under the car, doing the dirty work............ :lol:

I just want to say it sure is cool to be a proverbial mouse in the corner during some of these discussions.:thumbsup: :lateral:
Speed better provide the coverage this car deserves. Can't get enough of Marks Camaro's.:bow:

I put the two images together - hope you don't mind. This thing rocks!

http://www.daemoncustomauto.com/Medi...erged%20d2.jpg

Cool photo.

We are cranking away on it still. We are in the disillusionment stage or the program. Working real hard and it looks like nothing is happining.

If you want to see more geek squad stuff check out Ryan Kuhlenbeck's Excel Spreed Sheet for the wiring. This is from the learings on 3 LS9 projects and other projects he has worked on. The biggest problem is he lives in San Fran

http://i439.photobucket.com/albums/q..._silver_05.jpg

That is one page of 10+ with every wire, connector called out. It actually saves time if you need to trouble shoot the car.

It is great to work with a bunch of Engineers like Mikels, Kuhlenbeck, Rojewski, Gardner and Thomson :lateral:

Mark

Hey, would you be willing to share the LS9 Spreadsheet?

Also can you share your engine spec/cost?

I want to use an LS9 for my own project

Amit

Project update...

We have had the car back for 3 weeks and 2 days. Matt at Sled Alley is doing a great job getting the car ready to test.

All of the engine bay is almost done. A few small things left to do

http://i439.photobucket.com/albums/q...I/DSCN0001.jpg

The fuel pump contoller from Vapor Works. Diff over flow tank and fuel tank over flow tank.

http://i439.photobucket.com/albums/q...I/DSCN0014.jpg

http://i439.photobucket.com/albums/q...I/DSCN0029.jpg

http://i439.photobucket.com/albums/q...I/DSCN0021.jpg

http://i439.photobucket.com/albums/q...I/DSCN0016.jpg

http://i439.photobucket.com/albums/q...I/DSCN0006.jpg

Twin ZL-1 fuel pumps in a Ricks tank

http://i439.photobucket.com/albums/q...I/DSCN0015.jpg

http://i439.photobucket.com/albums/q...I/DSCN0030.jpg

Mark,It look's outstanding.:thumbsup: :thumbsup: :thumbsup:

Seeing your vision now Mark! Digging the stripe now!

ALL business!!! :thumbsup:

:cheering: :drool: :cheering: :drool:

Very nice!!! Only 47 days and counting until SEMA! :unibrow: