I have an 81 that I want to put a new engine in. My main question boils down to whether I should get a carb or fuel injected engine.
For example, the LS3 can be had for about $9k. A carb engine with similar hp/tq ratings runs about $4k. This trend is in general true, fuel injected engines cost significantly more than an engine with a carb.

Is it worth the extra money for fuel injection?

Also, 81 is the first year for a computer. How do these engines work with the computer and all the emissions controls? I know the LS3 has a separate control module so then I would assume it would work independent from the computer?

Thanks for any insight

 

have you ever drove a car with a LS series engine in it. 400+ hp and 25MPG is why so many people have done away with carbs. if you are not worried about fuel mileage and want a very simple engine swap then a new crate engine with a carb is the way to go.

What is wrong with the engine in your car now. if you simply want more hp and want to keep cost down you can have the engine in the car now rebuilt any way you want it

 

Well, Im gonna take a guess and figure that if you are contemplating putting in an LS motor, that you are considering substantial mutilation of the current emissions controls, computer, and various other related items.

With that said, it shouldnt be all that difficult to put another carbed small block in, and have it function perfectly well, with or without any of that stuff connected.

Personally, I would be inclined to keep it carbed for simplicity, and I would also disconnect half of the other "thinking" parts that GM put in there.

Depending on what you are looking to do, you may wish to consult with a local machine shop before you plop down good money for a crate motor. Back in 2002 I spent about $4500 building a 454 with a local machine shop. At the time a GM 454 h/o was about the same price possibly a little more, and there is no way it makes the power that mine does.

 

This is a big question. Need to know what kind of driver you are to make intellegent suggestions. Do you want to cruise? Do you want to race? If so drag race or road race or autocross? Are you mechanically savy? If not, do you have friends that are? Are you a Fuel-Injection and all-things-connected-to-a-computer hater? Do you have emissions to meet? Do you want original looking under the hood or not? How much will you drive the car? Is mileage important? Is being "green" important? How much can you spend? Does it have to be new or would you consider a used engine?

 

Thanks for the replies so far. I guess I need to provide some more details. I am doing a frame off resto on the car all by myself so whichever path I take Ill be doing all of the work. As far as having a preference between carb or fuel injection, Im much more familiar with fuel injection, having only owned and worked on fuel injected ones (except this one but I havent had it long). As of now (if it were finished haha) the car would only see the street but I plan on keeping it a long time (Im 26) and I cant see into the future.

As far as money goes, I have an idea of how much I want to spend on the whole project but if it ended up costing more, that would just mean it would take longer to finish as I earned the extra money. Obviously since Im considering an LS engine the money part isnt a huge deal.
Also I live in AZ so I will need to pass emissions. I believe we have a visual and sniffer test. This is one of my biggest concerns. I dont want to get everything finished and then be told I cant get it registered because I failed emissions.
Originality is of no concern to me. Actually, seeing something like an LS engine under the hood would bump the coolness factor up in my eyes.

So basically I want a streetable car that will be a blast to drive and reliable.

 

there are turnkey systems, but you really need to know and understand to some degree how the fuel injection works with all the computer controls.
you will need Oxygen sensors, and intake pressure, mass air flow, intake temp, spark knock sensors, and a host of other sensors and controlling things to attach to a computer controller box.. non of this would interface with your existing car computer, you will need a entire harness also to connect all this stuff.. in the end it will run great and get you 25+ mpg and be to some degree tuneable.

carbs are so much cheaper and work turnkey without a computer..

but still just search on this forum for people with carb tuning problems and you will see that carb tuning is not for the novice either.. most new carbs work right out of the box until people start messing with them...

 

From what you describe, I see you as a cruiser. If I were in your shoes, I would investigate a 5.3 LS/4L60E swap with an engine and trans from a Tahoe/Pickup/Suburban. The 5.3s are relatively inexpensive and you can buy harness and computer from Street and Performance. There is a thread going recently about just such a swap. I believe you need different accessories and possibly an intake. You can buy the engine and trans for less than $2000 (see www.car-part.com). Add another $2000 or so for wiring, computer programming, accesories, and incedentals. You could go full emissions with a cat I believe. You should talk to Mark at Street and Performance and/or go to their website. You can also spend a lot on a GMPP LS engine that is emissions legal.

 

There was a recent Car Craft project where they hopped up a truck 5.3 and made 400 HP and got 25mpg on 87 octane for like $4k.

 

That is what I am planning for my car. 5.3 from a late model pickup (available cheap anywhere) with a few mods (cam and rocker arms = 400hp) even with the harness and computer parts from S&P and a serpentine accessory drive, and some incedentals I am pretty sure I can be in for about $4400 in parts. About the same as a complete carb motor with new incedentals.

With this type of things available, I just cannot see building a carburated car unless you are going for originality. To each his own, but I want mine to be a trouble free driver.