MustangWorks.com - The Ford Mustang Power Source!

Go Back   MustangWorks.com : Ford Forums > Mustang & Ford Tech > Windsor Power
Register FAQ Members List Calendar

Notices


Reply
 
Thread Tools Rate Thread Display Modes
Old 04-26-2001, 07:17 PM   #21
Unit 5302
Registered Member
 
Join Date: May 1999
Posts: 5,246
Post

Hmmm... I'm looking at my car the way it sits.

87GT K&N panel, BBK 2.5" hiflow cats, 2.5" catback.

If it was in tune I could probably pull a 13.90@102 out of it with the 2.73's. If I slapped the right suspension setup and 4.10's or 4.55's on it, I'd be in the high 12's@104. This is with 145k miles on the block. Now that's all fine and dandy, but I don't want a racecar. I want a street car that I can have fun in the corners with, and get the best fuel economy with. Honestly dropping my gears to a 3.27 or 3.55 would probably do that in town, but it would hurt a little on the road.

Why carbs are inferior. Like my discussion noted with juiceman the carb cars form fuel droplets (in the intake) which decrease the overall efficiency of the intake air/fuel mixture. Droplets don't burn for **** and you wind up richening the mixture (so you don't burn lean) and blowing raw fuel out the exhaust. The only benefit to the raw fuel is cooling in the cylinder. This is where you lose fuel economy too by the way. Where you lose torque is the shorter runner intake. Due to opening intake valves single plane manifold cars get beaten down in a bad way. The disturbance at low rpms is significant enough to hamper air fuel mixture flow into the cylinder. They make more power up top because there is less restriction. Dual plane manifolds make better on the low end than single plane manifolds because they allow some extra distance from the intake valve which makes for smoother airflow at lower rpms; however, that limits the maximum potential of the manifold for high rpm usage by restrictions in the direct airpath into the engine. Due to the inability to tune a car to perfection (without running lean) you are going to lose all out power. You just can't get it to atomize perfect, which is also why if you look at a dyno sheet EFI vs carb straight up, the carb dyno will be wavy, where EFI will be smooth as a baby's bottom.

EFI manifolds feature long straight runners that optimize low end and midrange power. They are very resistant to turbulence created by the valves which enables them to smoothly flow air into the cylinders even at low rpms. Throttle response is much slower than carb due to the distance of the T/B from the heads. It has absolutely nothing to do with the computer, which is just as fast as the carbs manual throttle linkage in measureable input anyway. Under high rpms the manifolds begin to show more weakness, mostly because of the restriction the upper manifold creates in efficiently flowing air into the lower. Mustangbelle306 has experianced first hand what happens when you slap an unrestrictive plenum onto the EFI setup. You lose lot's of low end, and you gain on the top end. Basically the large opening hiflowing Cartech intake plenum makes the EFI lower into the equivelent of a single plane carb manifold.

Onto the actual performance of the venturi operated low pressure atomization of fuel with the carb to the forced atomization of the fuel injected car. EFI is superior to carbs when it comes to the perfect atomization in terms of airfuel ratio due to it's controlled environment. The carb, while good at initially atomizing the fuel, as was noted by juiceman himself, the intake manifolds tend to cause droplets to form with the fuel vapor forms on the ridges and imperfections. Since EFI injects the fuel just above the intake port on the head, this effect is minimized allowing for more accurate air/fuel ratio tuning. This is where you pick up your fuel economy and pass emissions folks.

How many times have you heard all the emissions **** hampers EFI? BS all over the place. The airpump has been around since the 1960's, my Uncle's 1969 Mach 1 428CJ has one. The O2 sensors input along will the rest of the input from emissions related components get ignored during wide open throttle acceleration on SEFI cars. Instead the computer defaults to a more aggressive performance database. That's what's called "Open Loop". The EFI cars also remain in open loop until the vehicle warms up. Ever wonder just how rich open loop is??? It's the equivelent of a sticking electric choke on a carb. Welcome to Mileage Reductionville. Ford intentionally made open loop run rich, especially on SD cars so that Joe Schmoe wouldn't be bringing his car back with a burned piston 35,999 miles after purchase. They made it run on the safe side of things. One of the major problems with the 5.0 Cobra computer is it's lack of speed switching to open loop running. Under WOT acceleration the Cobra computer remains in "closed loop" for a full 7 seconds before going into the performance oriented *laughs* (not really since the Cobra's computer takes out a shitload of timing and has sick *** fuel and timing curves) open loop cycle.

As far as reliablility. Any one saying a carb is as reliable as EFI needs to go back to the padded room. Why in the hell do you think people love EFI over carbs? Cause the ******* things start in the winter without pumping the gas pedal, even if you don't know how to tune them. For proper operation carbs MUST be tuned. Not everybody takes a course on how to properly tune carbs before they get their cars! I've personally seen EFI cars with 100,000mi on them and stock <insert explicative describing the people who do this> spark plugs!!! Vacuum leaks, cracked vacuum lines, necessary tuning, burned out electric chokes, inaccurate manual chokes, and overall irritability hurt carbed cars in reliability. When an EFI car has a problem, it usually ignores or compenstates for the lack of input data.

Unit 5302 on the conclusion. EFI car's that use the long runner type intake plenum suffer from intake restriction on the top, and single plane style intake lowers. Increasing the upper hurts low end, increasing the lower doesn't help top end (much). The properly tuned and matched upper/lower combo throw's a lot of that problem out the window, though. Carbs suffer from lack of low end torque, period. They can suffer from lack of upper end performance, but not to the significance of an EFI car with the plenum style intake. Due to the lack of accuracy in the fuel metering (no amount of tuning can perfect it), carbs lack optimal average hp and trade it for maximum peak hp. They do not dyno smoothly like the proper functioning EFI car will, and they lose average hp/torque performance because of it. As far as low end, the EFI has no near rivals, even the dual plane manifolds. True, you can eliminate bog with tuning, but even the best tune cannot compensate for the lack of low end grunt. The car won't BOG, it just lacks low end, as rpms increase the power output should be smooth with no lag time in power production. Obviously in a drag scenerio, you shouldn't ever be running at 2000 or 3000 rpms (you should have the tires and suspension to allow for only peak power running), which throws the carb's lack of low end out the window. On the street from a stop or slow roll EFI will exceed the carbs performance off the line considerably. The way EFI is tuned increases drivability significantly, it's smooth, predictable, and it's got excellent low end/mid range power production.

EFI when tuned WILL beat a carbed car hands down, (it requires a completely new computer calibration.) It WILL be a better street performer. It WILL provide significantly better fuel economy, especially due to the low end power's ability to run well with taller rear gears. It WILL be more reliable for the average person. It WON'T cost much more than a carb to get good street performance out of.

Carb when tuned WILL outpower an EFI car for absolute peak hp production. It WON'T be as streetable. It WON'T equal the economy of the EFI car, and it WON'T be as reliable.

As far as getting a carbed car to outperform the same EFI car with heads and a cam, you're outta your frickin mind. You obviously know less about how EFI works than I do about your carb.

Or are you saying you keep a bag of Juiceman's Magic Carb Powder in your shop. "Just sprinkle a little bit on the top of your carb and pick up 150hp!!!" If you do, that's great, I'm betting there are a few people who keep a bag of Magic EFI Whoop A$$ on their shelves. "Just get a little into your schrader valve and pick up 150hp!!!"
Unit 5302 is offline   Reply With Quote
Old 04-26-2001, 10:01 PM   #22
juiceman
Registered Member
 
Join Date: Jan 2001
Location: ny
Posts: 197
Post

well unit, i dont have the time to debate this with you.like i said, some of your points are correct but for the most part you must live in the world of perfect. how much do houses cost out there cause im sure we would all love to be there. you think injected cars compensate when theres a problem? youre just plain dumb with that statement. and you say i know nothing about injection. its a computer stupid. you do something as stupid as put in bigger injectors and you got problems. maybe you should look around and see all the problems there are with injected cars. a carb will always start. theres nothing there to mess up. i guess you know something about building race cars that the rest of the world doesnt. i dont know how we get those cars in the 6's with carbs. must be my damn magic carb powder again. and on low end grunt, carbs can do it. my stupid stang makes plenty of power down low. i leave like an animal and its an automatic.
look, the only good point you have is the atomization theory. and even your version of that is half wrong. i already agreed that if you got loads of money then injection is good, so why debate any further. rather let me help those in need since you obviously dont want knowledge.
now, red82gt , i would need to know more about your setup like what intake you use and other specifics but first like it was said the cam will want to make power at 3000. but i think you can work past that.
your timing at full advance should be 38 to start. this will help you out alot. also, i run the fuel at 7 psi although it doesnt make a difference in power it will matter when you start to launch the car hard. i see now that you have the offy 360 intake, theyre ok ,im not a big fan of them. i would go back to the holley carb. the 600 dp is good for you and will get you more power. when tuning that use 68/76 to start on the jets. also, make sure you have good alignment between the intake and head ports. this is important. next i would have used full length headers to get more torque.
your setup isnt bad but you made a high rpm setup and skimped on things. chances are you live out west so i can come and tune that thing. but i would start with the small stuff first like timing, 600 holley carb, tune etc. alot of people have bad times with carbs and give up, but you need to understand how they work and how to compensate. injection does the work for you, now you must do the work. if you are willing to do it i will help you through the process as best i can. i run into alot of guys like unit, and it dissapoints me how little the world knows i had the baddest car in 3 towns and never lost and the best was when i ran 2 cars, one was a white notch with juice which i toasted (n/a) and that cobra with his paxton. all i can say is that maybe one day ill run into you unit, but have the title signed and the account # to your bank.
anyone with a carbed stang on the east coast who has problems i am willing to go help. ill just let my work talk for me.
juiceman is offline   Reply With Quote
Old 04-26-2001, 10:55 PM   #23
Unit 5302
Registered Member
 
Join Date: May 1999
Posts: 5,246
Cool

Quote:
its a computer stupid. you do something as stupid as put in bigger injectors and you got problems.
Hmmm... sounds like you know absolutely jack about EFI. I've seen a SD car run fine after a 24lb injector swap (with idle surge.) 19lb injectors are good to the kind of hp you're talking about making with an intake swap. 350hp is just fine for them N/A, anyway.

Quote:
a carb will always start. theres nothing there to mess up
Guess that's why people didn't want to buy cars with carbs, instead they wanted EFI. Interestingly enough, I've owned 2 carbed cars, both 5.0's, and since I've been driving my family has had 7 carbed cars. If my dad didn't keep them tuned (he's the carb expert, not me), they don't like to start without a little fiddling. At Fed Ex, the only trucks that give us any problems starting when it's cold, or running (other than the diesels) are the carbs. EFI starts every time. Actually, my dad is damn good at carb tuning, kinda sick if you ask me. It's hilarious, here's this 62 year old guy out in the garage tuning a 3.3L inline 6 1 barrel!!! He managed to get the damn thing to run like nobody's business though. Pump it once, turn the key and it starts and run's like EFI. Course, he's been working with engines since he was 12.

Quote:
i guess you know something about building race cars that the rest of the world doesnt
Was I talking about building race cars? Nope. I prefer that you can drive it on the street. You don't need a race car to start when it's cold out, or pass emissions, or get good fuel economy.

Quote:
my stupid stang makes plenty of power down low. i leave like an animal and its an automatic.
How long does your carb stay between 2000-3500rpms? You have gears, yes? Converter? Torque multiplication is where you get your low end, not from the carb.

Quote:
all i can say is that maybe one day ill run into you unit, but have the title signed and the account # to your bank.
Hmmm... running my stock car with 2.73's versus a modded carb car? Maybe not for titles. I'd still race you, don't get me wrong, maybe for who buy's dinner. I'll race anything, even if I know I'm gonna get stomped.

I'm sure your car runs hard, I'm being serious. You should beat me, your modded, I've got jack for mods. I don't need them/want them at this moment. I have other places to spend my money. It's not that you can't build a seriously fast carb car, I'm not saying that at all. (Course, Magic Carb Powder is good stuff j/k.) That's been going on for 50 years. I'm just saying that IMHO based on what I have just stated in the theory of operation EFI is the better setup.

It sounds to me like you have as much interest in the aspects of EFI as I do about carbs.

EFI computers will compensate for some missing or seemingly corrupted data. Just like a carb, EFI isn't foolproof. You've still gotta match the setup, and tune it when it's modded. Some things cost more money to tune (most everything on EFI), but there are a lot of good points to it, and if you drive it hard, match the combo, and tune your EFI (where needed), you can pull some damn impressive times.

Anyway, I'm glad you can help the members of this board out with their carb problems. Hopefully you can get those guys running like crazy.

Later,
Unit 5302

oh btw, houses are as expensive as **** here right now. In the twin cities metro don't be looking for a 3bdr for under $250,000!!! What the hell? When did we become CA?
Unit 5302 is offline   Reply With Quote
Old 04-26-2001, 11:09 PM   #24
NOS_Notch
Registered Member
 
Join Date: Sep 2000
Location: Fresno,CA. USA
Posts: 384
Post

Ya know what???? i stopped reading after about the third post.
I run 13.20's on an all stock motor...12.50's on a 75 shot.
I like fuel injection...my dry kit wouldn't work w/out it.
If you like carbs..go for it...
Everyone is flaming each other..and if you spent more time time tuning your stang, then ragging on each other..you would be smoking those LS1's.....
In 3 weeks i will rip off some low 11sec passes...all for about 8 grand including my car....stangs rule...stop fighting.




------------------
4.10's,long tubes & 75 shot...Goes 12.50's
Check it out at http://www.burnouts.webprovider.com

11's coming soon!!!!
Heads,intake and cam are all here
NOS_Notch is offline   Reply With Quote
Old 04-26-2001, 11:17 PM   #25
NOS_Notch
Registered Member
 
Join Date: Sep 2000
Location: Fresno,CA. USA
Posts: 384
Post

hey unit.....
i live in fresno CA.
You can buy a 2500 sq. ft 5 BR house for about $160,000
Just so you know.....bob

------------------
4.10's,long tubes & 75 shot...Goes 12.50's
Check it out at http://www.burnouts.webprovider.com

11's coming soon!!!!
Heads,intake and cam are all here
NOS_Notch is offline   Reply With Quote
Old 04-26-2001, 11:23 PM   #26
juiceman
Registered Member
 
Join Date: Jan 2001
Location: ny
Posts: 197
Post

Hmmm... sounds like you know absolutely jack about EFI. I've seen a SD car run fine after a 24lb injector swap (with idle surge.)
looks like you just proved my point. thanks. next
here's this 62 year old guy out in the garage tuning a 3.3L inline 6 1 barrel!!! He managed to get the damn thing to run like nobody's business though. Pump it once, turn the key and it starts and run's like EFI. guess you proved my point there too. wow. next-
How long does your carb stay between 2000-3500rpms? its driven all day every day. its my every day car.
Hmmm... running my stock car with 2.73's versus a modded carb car? if you consider gears, carb, intake and headers modded then you shouldnt be giving advice on performance.
It sounds to me like you have as much interest in the aspects of EFI as I do about carbs. not only do i have interest but knowlege also. hey, i have already aggreed with you on the injection thing but when you look at the money to hp ratio the carb will win. so if someone turns to me and says " i have no money and this damn injection isnt cutting it, what can i do?" i say go carb. unfortunately most people dont have someone like your father or me around to tune the carb right but if you do, then take advantage of it. otherwise buy a laptop and tuning software and tune that injection. hell, i can do great things with an epoc system and i actually know what all that stuff is. but who has the money for that?

juiceman is offline   Reply With Quote
Old 04-26-2001, 11:32 PM   #27
NOS_Notch
Registered Member
 
Join Date: Sep 2000
Location: Fresno,CA. USA
Posts: 384
Post

i don't know what it is???
but i'm a white trash bastard....
And i like to play w/ myself.
So like i said b4...stop fighting.
Go smoke a vette or something.



------------------
4.10's,long tubes & 75 shot...Goes 12.50's
Check it out at http://www.burnouts.webprovider.com

11's coming soon!!!!
Heads,intake and cam are all here
NOS_Notch is offline   Reply With Quote
Old 04-27-2001, 03:38 AM   #28
Mustangbelle306
Yay for Chickys
 
Join Date: Feb 2001
Posts: 1,532
Post

Christ quit it already...I just wanted to know which parts I needed. This is completely asanine.

------------------
Elisha (Mustangbelle)
1994 GT: Cartech intake,4.10s, full exhaust, and pulleys.
Sold the 1986 LX sedan
http://www.geocities.com/mustangbelle_306
AOL name: GT306Chick

Mustangbelle306 is offline   Reply With Quote
Old 04-27-2001, 12:24 PM   #29
DirtKing
Registered Member
 
Join Date: Feb 1999
Location: brooklyn center,mn,USA
Posts: 169
Post

whatever your personal preference is you should be able to express it without getting personal. I don't see insults helping anyone. I've beaten both setups, and been beaten by both. alot of the time it come down to what area you want to excel in. No one application is superior ALL the time!!!

------------------
88LX notch, Speedpro EFI Procharged!
DirtKing is offline   Reply With Quote
Old 04-27-2001, 12:41 PM   #30
2FastLX
The Photoshop Guru
 
2FastLX's Avatar
 
Join Date: Feb 2001
Location: Mecca, Indiana
Posts: 1,419
Post

And the saga continues on!

All I gotta say is I have been ther, done that in regards to the whole carb thing. Now, I was never an expert on tuning a carb so i can't come in here and debate with these guys, but I can say this...
After tearing my engine's top end completely apart, doing some major head work, and swapping everything on the car with new parts I turned the key for the first time with the coil wire on and it fired right up and purred like a kitten.

I gotta vote for EFI. I knew absolutely nothing about EFI cars (do a search for AxemanZZ) when I came here and I redone everything on my car and put it back together and it runs great. I wouldn't have had as easy of a time as I did with a carb.

------------------
Too much to list. Best ET on the car so far with stock 2.73 gears - 13.73@102mph

Indiana Stangers Association
Buy your parts here
ICQ# 42269241
2FastLX is offline   Reply With Quote
Old 04-27-2001, 06:56 PM   #31
Unit 5302
Registered Member
 
Join Date: May 1999
Posts: 5,246
Post

I'd have to say nobody in this thread was flaming. Heated discussion with a little fun poking at each other.

God forbid a debate!
Unit 5302 is offline   Reply With Quote
Reply



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 06:27 AM.


SEARCH