Why not have the CSC feed the roots?
You could spin the roots slower, to the point where it would create say 4psi. It would make the system much easier to install, cheaper (no intake housing, just a bigger lower pulley), and it would give you a little boost off the line.

 

Why bother? All the naysayers will just ignore the truth or put their own spin on it.

You will post huge numbers. Then everyone will rush to defend their prior purchases, spouting off cliches about how your truck has no throttle response, isn't "streetable," is "for racing only," "not suitable for a heavy truck," blah blah blah.

All those wicked fast Grand Nationals, turbo Porsches, WRXs, etc are useless on the street and should be driven only to and from the drag strip. Positive displacement blowers are the only way to go with our trucks. Why even bother to offer a contrary viewpoint when the case has already been decided?

 

cough CRY BABY cough

Get over it........it was dead on arrival

 

jesus tim, can't it be remotely possible that maybe cent isn't a god send to lightnings? Simple fact is there is less power lower in the rpm band with a cent correct? And if not, can we please see how a truck does with a cent down the track and get some opinions on how they do on the street. Oh wait, no one has one running yet.

I don't think for a second that centifugals aren't streetable, or that they won't make results, but i do believe for a daily driver they won't be as ideal.

Btw, what porsche or wrx has a centifugal in it? The only car i can think of off hand that has a centifugal supercharger in it is the koenigsegg.

And crash has been ranting about cents for what? 2 year? 3 years? Never once have i seen a dyno sheet and a time slip for a centifugal truck. Maybe i just missed it?

 

My opinion is you don't know until you try. Everyone here that diss's the Cent has never had one on their lightning so they don't know how it would be.

Turbos dominate all of the supers.

 

Yes, IT IS. My complaint is that people are rejecting the possibility of the inverse.
Turbos (or, as they are sometimes called, "turbosuperchargers") build boost linearly like a centrifugal.
My hope was to offer another alternative to the Lightning community -- so that we could see those time slips. If people would have simply posted a thumbs up/thumbs down to a $4K cent system in this thread as requested, I might have been able to exert some influence at ATI to bring that closer to reality.

 

Thumbs DOWN

 

hmmmm, turbos yes, but turbos are more efficient than cents aren't they?

You know what tim, nothing but respect, because i think your a great asset to the community, but you know as soon as you say centifugal in a thread your going to have the opinions burst out. I'm not saying they won't do great, in fact, im pretty positive they are gonna be truly awesome, but from a streetable standpoint, im assuming not. But then again, we simply haven't seen the results yet. I think maybe you should hold off on this thread for awhile and wait til RDY2RACE or easter have their systems together and see what they can do. Once the results pour in and people can see and hear the opinions of people running centifugal systems the public is gonna open up. Make another thread then, don't immediatly say that people that don't want cents are ridiculous, and go from there. I'm sure if the results are good, you will find a market for it, it just needs to be proven. Aside from the chayenne, i can't think of a single vehicle in the lightnings weight class that has been successful with a linear boosting blower. And all respect to the car because it's damn fast for what it is, but it's still no track monster.

 

well my truck is up and running just waiting for a time slot on the mustangdyne. i have not seen or heard it run but will do my best to get pics and video of it.


just remember one thing. I HAVE A STOCK BLOCK. and we wont be turning up the boost right away. i'll be running a 4 inch pulley and a 9 inch lower for now til we actually see what boost levels we'll see outta this configuration.

depends on your definition of streetability but i think it will be no worse than a regular f-150 around town.

miloc has a track rental at milan dragway on the 24th if all goes well that will be my first track outting. then a week later we'll be at nmra columbus.

 

Excellent. I am interested in what kind of numbers you can lay down with about 16 PSIG or so. And I suspect that many others will be similarly interested. Because they are more efficient and lay down the power gradually, if 16 PSIG is safe with a roots, it would be really safe with a centrifugal (or a twin screw).

And a comparision at higher boost levels would not be fair, as the roots just cant run those pressure ratios efficiently.

 

we are going to shoot for 600 rwhp outta it closer to winter then we'll pull the block and build it if it survives.

 

Turbos are slightly more adiabatically efficient then cents, only because they are usually more closesly matched to the boost/flow curve of the engine they're on. The mechinism to compress the air is the same.
A Turbo's advantage is that it's not spun in a linear relationship to the rpm of the engine. Its RPM is completely independant of the engine's rpm. So if the exhaust can supply enough power at 1000rpms, the turbo can produce full boost then. The modulation of the wastegate will hold the boost at the commanded boost for the entire RPM range.
The turbo's down fall is that it uses exhaust backpressure to spin it. So you can't go with a crazy cam profile you can with a supercharged engine. Thats why you hear that you should run a NA cam profile on a turbo car.
Another advantage the CSC has is that you can run more peak boost. Detonation due to the heat of the intake charge is most likely to happen at torque peak. A CSC will produce less boost at the torque peak (even though a CSC will shift the torque peak up) allowing max boost at the HP peak. Also since a CSC engine won't see the exhaust back pressure of a turbo engine, you can run more peak boost.

 

there was a tuner at the dyno last week saying how a couple of guys have adapted the procharger kit for the cobra to a lightning and were putting out over 100 hp more with this set up than the roots style blower at the same boost levels.

I don't know what the exact details were and I don't know much about it, but Don's Bolt was there so maybe if he reads this he can fill in some info here. The guys seemed like a straight shooter and knew his stuff. He posts over on the mod motor board. Anyhow, he explained all the details about it and what not. Something about the amount of power it take to spin that eaton compared to a centrif and how with this kit, the intake charge is almost the same as the ambient temp and all kinds of good stuff..............or something.

 

His name was Mike Friedman (sp)

 

This can't possibly be true. Everyone knows that it won't work on our heavy trucks. Not streetable. No torque . . .

Just kidding. I won't go off on that rant again. I've taken my meds now and I'm all better.



Seriously, please post any info you have on what was required for the conversion. This is exactly what I want to do.