Yeah, you go over to Germany and can find cave paintings of carbs! Sheeesh, get with the times!

Gilly

Yeah, I bet Germans have no clue what a carb looks like. Mileage and pollution maybe, but I'd compare power any day. I tried a 900cfm Holley EFI for my chevota once. Mileage dropped 20%, and HP dropped even more, very dissapointing. After a month trying to get it to run like my carb I sent it back. I'm sure a real EFI would have been different, but beat the power of my carb? I doubt it. Cars I've dumped because of $$$ EFI trouble: Toy Celica, Honda Prelude, Toy 4X, and 300ZX. The EFI on my bmw works, but barely (it's gone soon). My old benz seems to run ok, but puts out 10 times the hydrocarbons it's supposed to (going soon too). Cars I've dumped because of a carb: None.
The computer and EFI are the only things that makes me nervous about my latest Benz. My other vehicles are all carburated and never leave me stranded. I know, behind the times, but I've been burned so many times it's hard to adjust uc.

I know many many people will argue the horspower issue with you. I know there are plenty of drag racers who would say you are a fool. However, you are correct about getting better mileage and lower emissions from an EFI system.

Actually I thought I'd take more heat from you guys over that carb comment. Give it a little more time I guess.
I know efi has the potential to beat a carb, I just think we’re still waiting on a management system to make it happen. I don't want to know how much it would cost to replace my carb with an equivalent efi system, I doubt one exists anyway, so I still believe the carb is the way to go for raw HP.
I’m bracing for the abuse to follow, no foul language please...;)

Autozen: Help me out here if I’m wrong, but Lambda means a typical closed loop system correct? From my semi limited knowledge, efi cannot make good full throttle power in closed loop. And I think it may even overheat the ex valves if you try it (educated guess). From what I understand, the O2 sensor cannot accurately read the mix needed for full throttle, so it goes into “open loop” mode. Open loop is programmed from the factory to dump X amount of fuel into the motor, and like a carb, this mix is probably not correct.

Chevota,

I promise; no abusive language. Hopefully we are too civilized for that here. That being said, you keep saying you put EFI on your car. I don't know how you can do that. It is all built in. Are you talking about installing one of the last American holdouts to keep from joining the rest of the world? Are you talking about Throttle Body Injection? I don't consider that fuel injection. A cheaper version of that is used all the time in shops to move cars around with a dead fuel pump. You get an apprentice to sit on the radiator support and continually spray carb cleaner down the air horn. A true fuel inj system be it CIS or EFI is built into the engine. You mentioned Toyota. Have you ever looked inside the plennum chamber of a late model Lexus V/8. There is another small throttle blade for each cyl. Man, do those cars scoot.

The lambda system has circuits built in too take wide open throttle into account. The engines don't necessarily operate in open loop unless you have a sluggish oxygen sensor. When you punch it to pass, extra fuel is supplied to compensate for the big hole you created in the intake manifold with the wide open throttle. You are not running rich at this point because you are supplying air also. The mixture should be close enough to that stoic thing that lambda can send a signal to trim the fuel for optimum power. I am not an engineer so don't hold me to exact details. This is just my basic understanding of how the systems work in general.:p

Peter

Yes, throttle body injection is what I tried on the chevota. It was somewhere between the carb cleaner inj and a carb. It's supposed to be a great setup, but it didn't like me n I didn't like it.
If you're not running too rich for the O2 sensor, then you're not making full power. The sensor tries to make the mix ideal for emissions which are too lean for max power, and from what I've heard, too rich for max mileage. When the computer goes into open loop mode it’s spraying fuel from a “map” generated at the factory that says; “well, gee, hmm, were at 3Krpm, full throttle and 195degrees, lets dump X amount of fuel.” The fuel map in my Holley system was programmable from a laptop in the field. I seriously doubt that’s the case with a typical car. That system, and every efi car I’ve had, can’t operate fast enough to be as responsive as a carb. My efi cars have all been very sluggish at low rpm’s or of the line, and my Mercedes are among the worst offenders.

Re Lexus: Sounds complicated and expensive. I would break it for sure.

since thread was bumped her is my say.
My AMG C36 has efi and AFRs on WOT are dead on all the way to the 7k redline at 12.6 to 12.8 which on NA is just the best range to make hp. Prob here is that if u mod ur car it is hard to increase fuel to match and here carbs and cis would be easier to work with.