EFI Vs. Carb

[Jmac05]

Can someone who knows tell me/us what the advatages/disadvantages are of having a carb over an EFI, and vice versa?

[tom hand]

EFI when it works correctly, will give better starting, gas mileage, and even can make the motor last longer. [oh I can't wait to hear the replies to that one] The main reason theystarted useing it was the meet the regulations that came out for polution control.
EFI gave the car makers greater control over how much gas they were dumping in the motor so the oil doesn't get containinated. It also has super trottle responce so the motor feels like it has a lot more horsepower than it actually has.The downside cost, motal humans can't work on them,you want a modified motor, [headers, cam, etc] the cost just to modifiy th EFI to work with them will cost more than a carb. The best part of EFI is mainly the WOW factor when you pop the hood.

[Michael A. K. G]

Tom Hand is right. EFI gives you much finer and more adaptive control over the fuel mixture. If you drive it to 10,000 feet from sea level, it figures out to lean the mixture. You get a dirty computer, and it still works. And there are MANY fewer moving parts to bend, get dirty, or wear out, in a fuel injector than in even a single-barrel carburator.

You also don't need separate injectors for idle, off-idle and WOT.

[67 SS]

They got it right on.Cost and ability to diagnose & calibrate EFI is your main deciding factors.Some sensors cost as much as a rebuild kit for a carb.

[Cheyenne Super]

I am definitely going with fuel injection. I am going to use Holleys mpi setup. The main reason is fuel injection can adjust infinitely to existing temp, barometric, and sea level conditions(as previously stated). The main reason I chose Holley is b/c they have a program that will work with cams with less than 112 degrees lobe separtion . A lot of other places require no less than 112 degrees. The cam I want has 110. Also, the Holley setup will allow you to tune in real time with a lap top or you can download fuelmaps from thier webstie to a 3.5 floppy then upload into the ecm.
Jmac05 makes a good point as well buy precisely measuring the amount of fuel you don't have to worry about washing the cylinders which will help engine life.

[nate68]

i've heard nothing but good about edelbrock's efi and nothing but bad about holley's efi (not being biased), if you dont have a laptop you're kinda screwed with the holley system, edelbrock's system has its own control panel thingy where u can have presets with the flip of a switch (i think). and you send them your cam specs and they send you a chip thats programmed for your cam, and if u change cams then u can order another chip. i'm stoked that they finally made one for vortec heads. too bad i cant afford it (college student) but when i can i'll buy the edelbrock setup. either that or buy my parents' maxima
if you're mainly going to drag race mainly then efi prolly isnt the best because they make a little less WOT power, carbs do a little better job at that (car craft did an article a while back)
you could always do a tpi conversion if you're not looking into making a ton of horsepower. Cheyenne super this might be something you could be interested in to go with a smaller cam. i dont know much about tpi swaps but some ppl on here have done them.

[minibike]

I am attempting the LT1 swap out of a 94 z28. You may find you can get an entire engine for what the fuel injection costs from Edelbrock or Holley. Since I haven't completed the project, I can't tell you how easy it was, but I plan on using a painless harness and stock computer.

[Jesse 67 c-10]

with fuel ingection doesn't the computer uses knock sensors and a computer controlled dist to adjust ignition advance in realtime depending on conditions, along with the fuel? if they don't, they should! do the edelbrock and holly systems have provisions for this? I would go for fuel injection in a heartbeat if I had the cash!
Jesse

[Cheyenne Super]

with holley's setup you don't have to have a lap top. that is just for real time adjustments. i will have a 550 hp 427 small block, so the only fuel injection kits mentioned that will support the full potential of my engine is the holley kit and the lt1.

as for knock sensors some kits do include those. but holley and edelbrock don't probably b/c they are asuming that you are going to run the best fuel possible in you "hot rod".

[Tennman]

I've had my ole truck for twenty one years now and it came with a 307,two barrel straight from the factory and i was getting around six and seven miles to the gallon. A year later i had a super runing three fifty engine,with a four barrel,and i installed it and it ran much better and also the mileage went to around ten to eleven mile to the gallon. As many of you know i restored the seventy one model, four by four and installed a five hundred and two cubic inch factory big block (five hundred and two horse version).I then installed a Holly Multi-Port system(GM didn't offer their tunnel ram at the time and Eldabrock didn't offer anything for my horsepower) and yes,you do have to have a laptop to program it,but,its so much more detailed and you can fine tune it anyway you want too,and when your done,just unplug it and off you go. I do carry my laptop with me if i'm going on a pretty long trip just incase i might need it,but i have never had to use it since i set it up for my use. By the way,now i'm getting fourteen to fiftheen miless per gallon !!!

[kxmotox247]

Tennman....sharp looking motor setup! Pretty nice looking bike in your avatar as well.

[ckhd]

14-15 mpg with a 502/502?!?!?


You gotta tell me the tranny/rear gear combo, and more about that FI setup.

[Michael A. K. G]

Originally posted by Jesse 67 c-10
with fuel ingection doesn't the computer uses knock sensors and a computer controlled dist to adjust ignition advance in realtime depending on conditions, along with the fuel? if they don't, they should!

Most, but not all, EFIs do just that.

Computer-controlled advance is extremely common, though there are a couple of vacuum/centrifugal advance setups running around (kinda silly if you ask me). Knock sensors are optional; they are a workaround for a potential detonation problem. Some have them, some don't.

EFI has two parts: fuel and spark control. They can be designed independently; one can be electronic, while the other is mechanical. You occasionally see electronic ignition with a carburator, and very seldom, a throttle-body injection unit (FI) with a points-type ignition and vacuum/centrifugal advance.

But you get far and above the best bang for your buck when both fuel and spark are electronically controlled. All late-model engines do just that (it's the transitional ones in the late 70's and early 80's that are hybrids).

[Tennman]

I'm running 35x12.50x15 BFG AT KO's with a 205 transfere,automatic tranny and 4:56 1/2 ton running gears. Tach turns about 3000 RPM's at 70mph. I would really like to change them in the future to a 3:73 gear ratio since i have plenty of low end torque. I tolerate it now only because i don't usually need the top end speed. But for cruising the interstates 3:73's would be alittle nicer ! Buy the way,the bike is for sale !!!