actually the drive efficiency is 96%

but the map efficiency is 76% max on your charger

 

The cobalts run a M62 from the factory...
Are they starting to use the TVR now? Any testing is better than no testing yea??

 

lists the 1320 as the smallest available now. I hope this is just old news and the 900 is out as well. Anyway, looks like a real sweet package! Here's the TE map for the 1320....

It' peak isn't the 74% of the rotrex, but it's pretty effin close! at least for pressure ratios of 1.6:1 (BTW, that's not a huge boost ratio...) And FWIW, 100 m^3/hr is about 60 cfm. I'm guessing that the 1320 at redline with a good head and exhaust would get you to about 70% TE..... Pretty sweet for an Eaton!

BTW, Audi will be using it on a 3 liter direct injection V6 (don't know what volume TVS though) and I think the new ZR1 Corvette is using it as well.

Matt

 

A) TVS not the TVR

and

2) ARE YOU EVEN FOLLOWING THE THREAD?! Who;s talking Factory?!

 

TVS S S S S S S S TVS

Not TVR

 

see he gets it... GAWD!!

 

Some people do their homework....

 

Sorry, musta been watching "Swordfish" when I typed that... haha...
Yes yes I'm paying attention.... Halley Berry just distract's me....

 

So run an oversized pulley with less boost???
Doesnt that defeat the purpose???

And before I get ripped, (cause I'm gonna), I am just trying to learn

 

way cooler man

 

the M62 projects I saw all but one was pushing 20+psi on a blower that shouldn't really be pushed past 15psi..... all you got was a car that made extreme heat and peaked at about 5800rpm

 

Roots blowers (what Eaton makes) are what's known as positive displacement air pumps. What that means in english is that for each revolution of the rotors, they move a fixed volume of air to the output. This is the "size" rating of the blower. The M45 moves 45 cubic inches per revolution, the M62 moves 62 cubic inches. So a bit less than 50% more. To get the same air flow when you move to the larger SC, you end up spinning the 62 at about 2/3rds the speed of the 45, and airflow is about the same (this ignores a couple things, but is a good first order approximation). So why would you do this? Cause of the thermal efficiency curves of the two SCs. As you go to higher air flows, the 45 really starts to hum and it starts getting less and less thermally efficient, where more and more of the boost is due to heat content as opposed to compression of the air. This is bad. With larger SCs, at higher airflows, you end up with less heating, more compression.

So, when you slap on a bigger SC and keep a reduction pully or whatever on it, you're really stuffing tons of air into the little engine. Yes boost goes through the roof, but there is only so much the little engine can swallow without bad things happening. Also, as you stuff tons and tons of air past the SC, something called the compression ratio starts to climb a bunch as well. If you look at the TE efficiency graph for the TVS1320 posted above, you see that there is an efficiency island where you get max TE as a fucntion of airflow and boost ratio. The key to designing a good kit isn't just stuffing really big stuff on the car, but making sure that the boost curve of the car ends up on or very near the peak of the efficiency island.

Most of the M62 attemps didn't do that good a job of doing this, and overdrove the SC for what the engine could digest, and didn't end up anywhere near the efficiency peak. So what you ended up with was a very miss-matched SC/engine combo and the project stalled. To make matters worse, the peak was missed to the wrong side (too much, not too little). Too much means things go boom when you try to hit redline, to little means you tune the system for more but keep driving to the shop, as opposed to being taken there on a flat bed truck.

So Jans comment about the boost levels means that the apps that crossed his desk were running too high a boost ratio for the blower.

Hope this helps,

Matt

 

Thanks Matt

 

Wow...
Good stuff!!! I understood about, 2/3rd's of it, but good stuff to refer to and thanks for taking the time to enlighten me Matt... Again....

 

Yea that seriosuly helped. But ill have to look into it more. Im loving the idea of a new super charger. Hope Jan can get it to work out as somthing along the lines of a bolt on cuz id def. be in line to buy one . hahah

 

Yes it will. It also will be around $115,000.oo

http://www.youtube.com/watch?v=QothBmcy5Hg

Your going to love this.

Longboard

 

Holy crap that .......was........awesome. Cool to watch, I don't think I have the nerves for that type of speed and action.

 

Uhh....wow!
I started flinching when he hit 177 and that wall was coming up fast!

 

That's a stock ZR1 on street tires . I here top speed is around 210MPH

Longboard

 

Yeah....the ZR1 is a pretty bad beast. Something else consider about that video, they had a very strong head wind on the long straight (i want to say it was 20+mph), and the driver was GMs Suspension Guru, not even a 'racecar' driver.... So there may be a few more seconds in that car, on that track.