problem with the supercharger? - Page 2

Jul 14, 2005 | 10:30 AM

#26

E55AMG99

MBWorld Fanatic!

Joined: Mar 2003

Posts: 3,445

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From: WOT somewhere in the Bay Area

1951 Caterpiller D6

Quote:

Originally Posted by e55 baller

thats what RPM Racing told me today about C02. Also NOS/Lb is like $7 vs. $2 for Co2.

They said they could hook up the C02 system so that it doesn't make its way into the engine...would just freeze the air on the way in and lower the charge to below ambient. Saber has done this mod. Looking to learn more about it.

I assume having a modded ECU is a no go for a dry 50 shot. Looks like Derek has gone with an 85 wet kit and the others on this board running NOS seem to have a stock ECU. I guess there may not be enough fuel left over.

Btw what size injectors are in our car?

Thanks.

I'd be a little skeptical of their claim that they can design a system that doesn't allow any CO2 into the intake stream. The ice that results is from the moisture in the air along with a small amount of CO2 that is momentarily frozen. However, it will rapidly vaporize and the concentration of CO2 under the hood will rise and displace some O2. How much is anyone's guess but even a small amount would mean a drop in performance much like an increase in altitude.

As for the 50HP dry shot and a modified ECU, you need to know more information. Specifically, the capacity of the fuel system (delivery pressure and volume), the rating of the fuel injectors and the maximum duty cycle (how long they remain on during each firing pulse). A good set of dyno runs with A/F readings is a must as well. Some charts I've seen with modified ECU show a remarkably flat A/F ratio that is closer to stochiometric than stock. Shorter pulse width on the injector firing could be all that is happening. If that is the case and the tuner left the headrooom in it to automatically compensate for more O2, a 50HP dry shot is a no brainer. On the other hand, if you also have a pulley, you will have less margin to add a dry shot since you are already puming in more air.

My advice is talk to the ECU tuner and see if they are willing to divulge any of this information or lead you in the right direction.

Complicated? Yes! But the rewards are awesome, right?

Best of luck,
Greg