Why convert EFI to Carbs!?

[u3b3rg33k]

Since i've helped dyno tune several DEI cars to make over 850 horsepower. Let me know when you do this with 358 CUI N/A. I've done the flow benching, I've set the carbs up, i've flow benched the heads with the carb vs throttlebody. Let me know when you replace your cam and lifters with electronicly controlled soleniods then bring up f1. Do the dyno time, and real world work on the actual cars and come back talk. Theres a reason nascar ditched the fuel injected idea. yea they go around in circles like fags on a track, but the engine building and R&D is top notch, which I have participated in.

Welcome to 2012, bro. it's the year of EFI.

Another way to look at it:
Even NASCAR has finally seen the light at the end of the tunnel, and this time it's NOT the headlamp of an oncoming train. They're predicting BOTH better fuel economy, AND more power.

I guess they just couldn't afford the carburetors that were better than a silly McLaren EFI setup.

[nando]

I've told you how long it took me to do all that 15mins, and your fuel maps and spark maps aren't making 850 horsepower are they? You dont need a dyno, because you dont have a real racecar making 850+ rwhp. 1 full throttle pull , jet up, another pull see if it responds well, etc. It makes more power thru FLOWING MORE AIR / FUEL at PEAK RPM's within they class of 850 cfm because they are not all "850 cfm" per say. A flowbench will tell you that. gah mods can't stand to be wrong can they.

they aren't making 850 hp because they're running a fucking M20. They could easily make 850hp on the same engine, and get better fuel economy, and essentially never need retuned again.

HP IS NOT DETERMINED BY YOUR FUEL METERING DEVICE UNLESS THE THROTTLE IS TOO SMALL. how can I make that any more clear? how does the fucking computer limit airflow? it doesn't!

jesus H christ, some buddy of yours lets you watch them build an engine and you think you know everything now?

[LJ851]

Correct it will make more broader power, but in a racecar, you're at WOT high rpm's anyway. The carbs will make more peak Horsepower, and Lets see someone change out there injectors in a couple mins to correct their horsepower for different weather conditions. I am a FI guy myself, but to say FI will always win isn't something I will agree with.

And that doesnt seem correct, ITB's are best when tuned to a narrow specific powerband, The make the trumppets at different lengths to try and smooth this out.

The benifit is PEAK POWER and ease of tunablity. Theres a reason most drag cars aren't fuel injected either. Lots of ignorance in this thread.

Until people have seen or put a racecar making 800+ horsepower on the dyno and tuned to make 850+ within 15mins, with their hands, stop posting things you've read on wikipedia.

Sorry, Nascar boy, you have your head up your ass.

I have spent many years building and dyno tuning race and street engines so this isnt wiki knowledge.

No one here has a Nascar sized budget to work with either.

That 15 min of fine tuning you speak of is because of countless hours and time in the past to figure out what works the best on those engines, it does not apply here.


Nobody is asking to put a four barrel on their bmw engine (although it would work very well)

Your statement about changing injectors shows how little you know about tuning efi.

[nando]

Your statement about changing injectors shows how little you know about tuning efi.

basically, this. NFC.

[LJ851]

This one sounds like it is struggling.

[xwill112x]

Sorry, Nascar boy, you have your head up your ass.

I have spent many years building and dyno tuning race and street engines so this isnt wiki knowledge.

No one here has a Nascar sized budget to work with either.

That 15 min of fine tuning you speak of is because of countless hours and time in the past to figure out what works the best on those engines, it does not apply here.


Nobody is asking to put a four barrel on their bmw engine (although it would work very well)

Your statement about changing injectors shows how little you know about tuning efi.

I was referring to race engines in general, and my post wasn't entirely directed at you. I was comparing changing the injectors vs jets, and the ease of tuning both. And the 15 mins of fine tuning has some from years of R&D but isnt it the same with your computer based maps?

Not saying you dont know your shit either, but CARB's obviously win at the end of the day, with PEAK POWER AT WOT. thats been my point in this entire thread. But give me a race engine with direct injection, and I will gladly take that over carbs ;)

Welcome to 2012, bro. it's the year of EFI.

Another way to look at it:

Even NASCAR has finally seen the light at the end of the tunnel, and this time it's NOT the headlamp of an oncoming train. They're predicting BOTH better fuel economy, AND more power.

I guess they just couldn't afford the carburetors that were better than a silly McLaren EFI setup.

just like last year right? and the year before that right? And you are correct about the predictions.

they aren't making 850 hp because they're running a fucking M20. They could easily make 850hp on the same engine, and get better fuel economy, and essentially never need retuned again.


HP IS NOT DETERMINED BY YOUR FUEL METERING DEVICE UNLESS THE THROTTLE IS TOO SMALL. how can I make that any more clear? how does the fucking computer limit airflow? it doesn't!


jesus H christ, some buddy of yours lets you watch them build an engine and you think you know everything now?

No sir I've built a couple 358's , not just watched ;), Horsepower is limited by how much energy you can burn aka how much fuel and air you can pump through the engine effieciently. and Really? I thought if you had to big of a carb you wont have hardly any horsepwer, as you cannot get any velecity with the air moving thru the venturi. So...WRONG. :) I haven't claimed to know everything, just simple facts.

[nando]

Not saying you dont know your shit either, but CARB's obviously win at the end of the day, with PEAK POWER AT WOT. thats been my point in this entire thread. But give me a race engine with direct injection, and I will gladly take that over carbs ;)

Which is flat out WRONG.

your head is so far up your ass.. you can't make more peak HP just because of the way you're metering fuel. If you can't make 850hp on the same engine with EFI, change your throttle body to something larger. an EFI system isn't "HP limited". There's no magical HP limit on Megasquirt, or Haltech, or Pectel. hell, there's no magical limit on the 30 year old Motronic 1.3.

why would you ever need to change your injectors? see those little numers in the VE map? make them larger - BAM! more fuel. If they were too small, you could also bump up your fuel pressure.

Tune going out because of ambeint conditions? LOL. You've got it backwards, buddy.

15 mintes is probably too long. It probably takes 5 or less. And no, that's not with 15 years of experience. that's an AFR/Lambda target map, a wideband sensor, and an algorithm that automates the analysis of sensor data and corrects the VE table in real-time. You don't even really have to know how it works.

[u3b3rg33k]

If fuel injection ALWAYS WINS, I want to see a FI setup making 5000+ horsepwer and drink the rate of fuel as the top fuel dragsters do. Please show me so I can enlighten the rest of the racing world.

And again, I'm a FI guy, but not for a racecar. Simple as that. Theres a reason all the big boys in Drag racing and Nascar use CARBS. Funny huh?

http://www.carcraft.com/techarticles/ccrp_1009_8000hp_top_fuel_engine/viewall.html

Oops. 8000HP, and 42 fuel injectors, guess those 5000hp carbed versions are, oh, right.

Got a link to a current top fuel car that doesn't use fuel injection?

[LJ851]

but in a racecar

Racecar!

Lets see someone change out there injectors in a couple mins to correct their horsepower for different weather conditions. I am a FI guy myself

Oh really? Correcting a FI engine for weather conditions? What, do you have Hilborn FI ?

Theres a reason most drag cars aren't fuel injected either.

Because America! (hillbilly)

Lots of ignorance in this thread.

Yes, there is (ahem)

Until people have seen or put a racecar...

Racecar!

because you dont have a real racecar

Racecar!

If fuel injection ALWAYS WINS, I want to see a FI setup making 5000+ horsepwer and drink the rate of fuel as the top fuel dragsters do.

They have rules to follow. It is amazing what they accomplish without electronics, truly. One of a kind motorsport!

And again, I'm a FI guy, but not for a racecar. Simple as that. Theres a reason all the big boys in Drag racing and Nascar use CARBS. Funny huh?

Racecar!

Yes, they have rules to follow. Hell, Nascar is restricted anyway, Poor example for a maximum power debate.

[xwill112x]

http://www.carcraft.com/techarticles...e/viewall.html

Oops. 8000HP, and 42 fuel injectors, guess those 5000hp carbed versions are, oh, right.

Got a link to a current top fuel car that doesn't use fuel injection?

Got me there. I'll admit. but 42 injectorss? I always thought it was around 10? Lol

[u3b3rg33k]

Another one:

http://www.carcraft.com/techarticles/carburetor_vs_injection/index.html

And before you say it (check the date), GDI.

just like last year right? and the year before that right? And you are correct about the predictions.

http://www.nascar.com/news/111018/in...tor/index.html

NASCAR's decision to require fuel injection for Sprint Cup engines beginning with the 2012 season.

[LJ851]

Not saying you dont know your shit either, but CARB's obviously win at the end of the day, with PEAK POWER AT WOT. thats been my point in this entire thread.

This is exactly where you are wrong. A carb is just a fuel metering device.

and Really? I thought if you had to big of a carb you wont have hardly any horsepwer, as you cannot get any velecity with the air moving thru the venturi.

The horsepower loss does not come from the lack of velocity in the carb, the engine doesn't care about that. It comes from the fact that a carb will not meter accurately at too low a velocity.

This is the compromise of a carb. Big enough to make max hp? Then power will suffer at low and mid RPM's (partial and particularly WOT)

Small enough to make full power at low and mid RPM's? Max power will suffer.

A four barrel carb does not have these problems as badly as a sidedraft carb does.

[slammin.e28]

I thought a carb was a unit of heat?

Fuck that. I'll stick with EFI. I don't want my engine getting too hot by bolting one of those damn things on the side/top of it.

[Jhonno]

I thought a carb was a unit of heat?

Fuck that. I'll stick with EFI. I don't want my engine getting too hot by bolting one of those damn things on the side/top of it.

Calorie?

[LJ851]

^slammin is so concerned about retaining his girlish figure for lambo that he is not thinking clearly.