What are the advanteges of a fuel injected system to that of a carburator? Why do some people remove there fuel injection and carb it and vice versa? Thanks for any input. ~ Arnold

 

Fuel injection is 2-3 mpg more efficient than carbs. Fuel injection is emissions legel in alot more areas. Carbs run a little rough for the first 3 minutes. Other than that, carbs take the cake very convincingly IMHO. I'm not going back to FI.

------------------
"American made baby. 100% American iron. The muscle among the masses. My hero. Yep, you can take your ergonomically designed, space age, computer controlled, 4 door, cup holding map lighted split double wishbone split fold down retractable cargo covered moon roof piece of transportation and keep it. For I have felt the thunder. And I know the difference!"
JSP Motorsports
ICON Motorsports

 

Fuel injection is a wonderful thing my friend. I would switch over tomarro if I could afford it. It is more efficient and a lot less of a pain in the a$$. On the other hand, it is much more expensive. A fuel injected ride is more friendly to drive on a daily basis and you don't need to adjust it during changes of seasons. Hmmmm, I wonder why no automobiles are coming out of the factories carbed any more?

------------------
1983 Camaro Z28
Goodwrench 350ci V8, Edelbrock TES Headers, Flowmaster Catback, MSD 6al and Blaster 2 coil, Edelbrock Performer intake, Edelbrock Performer 600cfm carb. T5, 373 rear, Eibach springs, Cervin Vega speakers, Rock. Fos. Sub, Pioneer CD,
email-chris4421@hotmail.com
-------------------------
"I used to be a Mustang Guy! I didn't know the power of the dark side!!"

 

For the exact same reasons you can't get 500hp big blocks from the factory anymore. EMISSIONS!!!!!!
well..that and idiot laymen who don't tune up thier cars for 100k miles.

Go look at how high a percentage of cars that run 11's or faster NA are carbed (even million+ dollar race cars)..and tell me FI is really so much better.

------------------
"American made baby. 100% American iron. The muscle among the masses. My hero. Yep, you can take your ergonomically designed, space age, computer controlled, 4 door, cup holding map lighted split double wishbone split fold down retractable cargo covered moon roof piece of transportation and keep it. For I have felt the thunder. And I know the difference!"
JSP Motorsports
ICON Motorsports

 

Hey,

I removed the TPI from my car in favor of carburation. (With the help of Jester's article)
I went to a carb because I have a heavily modified engine, and the TPI with it's computer chip was not adept at handling the extra air and fuel delivery.
Also, I wanted to run a blower, so using a carb with a roots blower is a much easier install, cheaper parts, and easier to tune. I don't need scanners, special chips, or anything like that. The car is harder to start in the cold, but so what.

On my stock 89 Formula 350, I have left everything alone. It is nice to have that car EFI so it gets a little better mileage, starts up nice and easy, and I don't really have to adjust anything. But driving the car with carb/blower is a lot more fun!

Philly

 

I switched from tbi to carb. Am very happy with the switch myself. My fuel mileage did drop, about 9%. But the benfits from being able to make mods has increased 10 fold. I just swapped in a 350 from the 305. The mods that I'm going to make to the 350 will no longer cause headaches from the computer, cause it's GONE. A 9% loss of mileage isn't too bad really.

 

Boy, talk about a hot button!

The first question you have to ask yourself is: What do I want to do with this car? The answer to that question will determine your path as you answer the questions that naturally follow. If you want a street/strip car that is easy to start, gets decent mileage, holds its own on the strip, and money isn't your primary limitation, then you're looking at FI. If you want to keep expenses down and are willing to sacrifice some driveability and fuel economy, then carb's your path. If you have to pass visual emissions inspection, you may not have a choice.

I know you're resorting to hyperbole, Jester, but no factory put out streetable 500 HP cars (even gross HP). What they're doing now with computer contolled FI is streetable and is approaching that magic HP number (in gross numbers, at least). I've never seen a NA carb car that ran even 12's and could cruise all day & night down the boulevard. I do know, however, of a particular FI Vette that runs low 12's at 5800 ft and purrs like a kitten on the street.

Personally, I'm keeping the carb when I up the ponies. But, if I fail emissions in September, I'll be scrambling to get that TPI swapped in quick, you can be sure. If I pass with the carb, I'll be selling the TPI.

------------------
82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R. 2.73 unlimited slip. Cat-back from '91 GTA, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LB9 w/ZZ3 cam, TBD heads, exhaust, paint, etc.).
57 Bel Air, my 1st car. 0.030 over 396, Weiand Action+, Edelbrock 1901 Q-Jet, Jacobs Omnipack, 1-3/4" headers, TH400 w/TCI Sat Night Special conv & shift kit, 3.08 10-bolt, AMSOIL syn lubes bumper-to-bumper. Best 15.1 @ 5800' Bandimere. Daily driver while Camaro was being put together.

 

For a car that you plan to keep stock or only modify once, I'd say fuel injection is the only way. The advantage to a carb is that it can be tuned mechanically to your application, without a lot of chip-burning and swapping. It's all a matter of how much patience you have and what your plans for your car are.

CC carbs suck though...my opinion. Worst of both worlds.

 

Well..I was was referring to the original LS6. I know it wasn't officially rated at 500, but it was often said to be underrated, and really over 5 bone stock. Given the 454ci, 11.25 (IIRC) compression, and lopey cam, I believe it.

------------------
"American made baby. 100% American iron. The muscle among the masses. My hero. Yep, you can take your ergonomically designed, space age, computer controlled, 4 door, cup holding map lighted split double wishbone split fold down retractable cargo covered moon roof piece of transportation and keep it. For I have felt the thunder. And I know the difference!"
JSP Motorsports
ICON Motorsports

 

Thanks for all of the replys. I have seen some people say that carburators aren't as "drivable". What exactly is meant by that? Is it not advisable to drive long periods of time with a carburator or what? Thanks. ~ Arnold

 

Before the recent FI setups were out and running the only FI system was mechanical, for the street that is. Cars ran on carbs for a long time, streetable to me just means you can drive it on the street without having to operate it at high rpms.

 

Okay well, look below, it runs 11s, Stroker power, and I still cruise in it. Only prob is the gas mileage kicks my @$$ cause of gears. You said you will sell your TPI, how much? I am very interested!

------------------
Chris "$teve" Williams
1984 Firebird "Stroker GT
2 1978 WS6 Trans AMs (one of which is a "T/A 6.6" 220 hp.)
http://www.geocities.com/butterscotch_kandy



[This message has been edited by DaBandit (edited January 02, 2001).]

 

I just replaced my V6 with a 350 and it's carbed. Runs fine, and starts a bit hard due to timing being retarded a bit to eliminate knock, but when I step on the gas I'm gone.
I'll never go to FI. Waste of time and money IMO. And come emission time, here in Tacoma Wa. there is no visual and if I fail the sniff test I'll just detune the carb and pour in some ISO Alcohol and that should do it.


------------------
1986 RS Camaro
Mods: Threw 2.8 in garbage, put in rebuilt
350 .060 over, XE268H Comp cam, Edlebrock
Performer Intake and Edlebrock 600 CFM Carb,
Pete Jackson noisy GearDrive (which sounded
cool for about 5 minutes, now I'm sick of it)
Rebuilt TH350, 3.42 slippage in the rear.
Killer Power, OH YEAH!!!!
Gonna blow up that V6 rear real soon

 

The LS6 was the best engine in the world, IMO. It had 450hp and 500lbs out of the box. My experience is quicker throttle response with carb. Other people tell me the oposite. I love the tunability of carb.

------------------
'82 Firebird, dead stock, 9 bolt disc rear, over 200,000 miles and still going strong, more to come...

 

I am thinking of switching to TPI as soon as I can afford it. Unless of course I learn to tune my carb before I get the cash for the TPI. I love the power of the carb and the lower prices, but sometimes it runs great, then other times it runs like crap. I know it's not the carbs fault, it's mine. I just need to learn to tune the darn thing.

------------------
Zepher
'86 Pontiac Trans Am WS6, LG4 305, 5 Speed, CF DF Clutch,
Edelbrock 1406 Carb, Edelbrock Performer RPM 7101 Intake Manifold.
Edelbrock Open Element Air Cleaner: Flowmaster Exhaust, 160* Thermostat,
Grant GT Steering Wheel, MSD HEI Coil, Taylor 8mm Wires, Leather 96 Camaro SS Seats,
Alpine CD+Changer,Alpine V12 Amps, Premier TS-1040C Subs, Polk Audio highs/mids.
Best ET: 14.94@91.67
High Speed Run: 157mph
WS6 Trans Am

 

This issue must be looked at from two different angles. I you are building a fire breathing drag machine, I agree with a carb. If you are building a semi quick everyday driver, fuel injection is the most reliable and economical way to go. Most people are not carb tuning gurus and will never get their carb tuned perfectly (me being one of them). Fuel injection takes out the guess work. You can still tune fuel injection as well. Technology is the key. You may get higher peak hp from a carb, but on a street machine, you will get more area under the horsepower curve with fuel injection. Besides, who dosen't like getting 2-3 mpg better?

------------------
1983 Camaro Z28
Goodwrench 350ci V8, Edelbrock TES Headers, Flowmaster Catback, MSD 6al and Blaster 2 coil, Edelbrock Performer intake, Edelbrock Performer 600cfm carb. T5, 373 rear, Eibach springs, Cervin Vega speakers, Rock. Fos. Sub, Pioneer CD,
email-chris4421@hotmail.com
-------------------------
"I used to be a Mustang Guy! I didn't know the power of the dark side!!"

 

fortunatly there are FI systems out there that could kick the unholy **** out of any carbed system. the way they do it...

They are tunable from inside the car. you mount a little lcd screen in your dash, or a little **** with some, and decide your fuel mixture, and even timing i believe. so you get your 350 up to 550 horse, then horribly down tune you fuel mixture when you want the MPGs. it so beautiful. i think holley and edelbrock (sp?) sell versions. i really want one for my vette, but at arround $3000, ill probably just buy a 900cfm double pumper. The Ta will probably get the vettes 795cfm Q-jet

[This message has been edited by 85ws6TA (edited January 07, 2001).]

 

this is a debate on a carb board....go to the TPI board and you will see the oppsite of what was said....Fuel Injection is still a "New" thing. Gms first attemp at electronic FI was the cross fire...TPI was it second attemp.... lets see put a carb on an LS1, tune it.....i will bet the FI will beat the pants off the carb, better Fuel eco., more power and better relaibilty, no hard starts....etc etc...if you are gonna argue this give it a fair fight and go to the general board and explain what you are doing so they don't move it.

 

I'll second that opinion. You can adjust your rich and lean stops all day long and have no idea what it'll do. Makes much less sense than simply switching jets/rods (or injectors for that matter).

 

I'm going to move from FI to Carb... well not really it's a whole new motor so I figured it would be a hell of a lot easier to slap a Victor JR with 750 Speed Demon DP on than for me to try to fix up a miniram and DFI system. Not to mention I didn't really feel like spending tons of money on new FI stuff. When I could net about everything I need for around 1k... which would be the cost of the new miniram probably.

+ I'll have the TPI on the stock 350 if I ever want to swap that back in.

 

i sent you mail as i have a complete tpi set up for sale off a 85 vette.

 

lmao that post is from 2 years ago

 

one thing for sure fuel injected engines last much longer..........carbs contaminate the oil much quicker causing accellerated engine wear.....i've seen plenty of 200 thous mile FI engines running well...very few carbed engines see that mileage

 

Not true. You are comparing new cars (FI) and older cars (carbs). If you compare the exact car with the same engine (only changing the FI/carb) they would be similiar in how long they last. The big myth with carbs is that you must adjust them all the time, make changes when it's cold or hot (with the seasons). The problem I see with carbs is that it's getting really hard to find a shop that can actually fix a carb, install an aftermarket carb and adjust it correctly, or even adjust/troubleshoot a carb at all. If I couldn't do all that myself I probably wouldn't own a carbed car for a daily driver.

 

where do you think all the fuel that doesn't get mixed with o2 go......in yer pocket?

 

Why do all the go-fast guys run carbs? Cause TPI can't hang!!!!!!!!!

 

I noticed no loss in anything switching to carb...it idles better than my TBI and starts easier.

Carb is the easy way to go. Its simple to tune and easy to work on. I like it. Id only consider maybe a MPFI system over carb.

Carb on mild motors is 100% streetable...mine will idle as long as i wish, run good, gets decent milage, and its cheaper.

I don't regret the swap at all.

 

I have a carb and the one thing that I hate the most is when its hot out u get a big time drop in power. My ET improved by half a second from a 20 degree change.

 

Personally I would say a FI would be the way to go if you have the time, money, and knowledge to tune it correctly (like a DFI) depending on the application. But in my case just slapping a motor together converting TPI to carb was a lot cheaper for me than going and getting a miniram, injectors, computer system and other stuff + learning how to tune everything.

We can all go back and forth all day long on the differences between the two.

It just all comes back to how much money you want to give up to GO Fast and how much time you have on your hands.

 

personally i think it's a fact that fi is just plain better than carb, for street use of course. Not that carbs are "bad". Heck i still drive carbed cars regularly, i'd rather have a fi system, but oh well...carb works too. The only disadvantage to a fi setup is the price, you could buy a whole engine for the price of most aftermarket fi systems.

Plus...there's a few fi production cars that make 500+ horspower. New viper comes to mind. Thats kind of a loaded statement though. How many production cars make 500 hp period? not many....

Personally i'd love to see a fi Ls6 (old version). that'd be a pretty impressive machine, and its possible to do.

For your application, the only advantage of switching from a tpi to a carb would be adjustability. The tpi system is designed to work with a pretty specific set of parameters, you really can not adjust the stock tpi system at all. Unless you want to get a chip burnt, and even with that you still have limitations. It's more efficient, and more precise than a carb. Personally i just like the throttle response you get with fi as apposed to carbs. It's a night and day difference.

The carb...i'ts actually a lot more complicated that the tpi, but you can basically adjust it any way you want it. As long as you have the knowhow. Of course...if you dont have any major modifications to your engine, you really wont gain a whole lot from switching induction systems.

 

TPIS chart.

 

My car used to stumble around in 100 degree weather if I sat idling for awhile. 3'' cervini cowl fixed that. I am also getting some coated hedman longtubes also. Should cut down the unhood temp somewhat. If you ran a ram air/CAI setup you shouldn't stumble around at all. One of those RAM air boxes would probably cure it. I may get one to see if it helps. Even though I have a cowl hood.

 

If you're very good at tuning a carb you can tinker with it and get excellent gas mileage.

 

if your making any kind of non daily driver.. with some power... i'd certainly suggest going carb... and a holley at that. They are so tuneable...other carbs seem like self abuse.

You will go faster, much more easily, much sooner with a carb.

there is much less to go wrong. and it's all uncomplicated. all the things you'd want with a "play car"

As far as "driveability" at best it's dead even. a well setup holley.. even a vac sec one will have better throttle response than a tuned port motor.



EFI is great for one thing.... Keeping me in business.... i'm an auto mechanic

 

Haha...I haven't had many problems at all with my car since I switched to carb. Runs much better than the TBI ever did. I changed every sensor on that TBI and it still ran bad. Switched to carb and I've been happy since.

The first week or so of carb kinda sucked...I had no idea what I was doing. Finally figured it out and its great.