LS-carb or fuel injected?????

[RdHuggr68]

I am toying with the idea of putting a carb on an LS3. I want to keep some old style look of the carb on my 68 Camaro but don't want to loose any performance from the LS3 either. Any suggestions? :hairpullout:

[71RS/SS396]

If you like the old school look. Why not go with a carb intake and one of the aftermarket efi set-ups like Fast, MSD, Holley....etc? Then you'll have the best of both worlds.

[RdHuggr68]

If you like the old school look. Why not go with a carb intake and one of the aftermarket efi set-ups like Fast, MSD, Holley....etc? Then you'll have the best of both worlds.

I thought about that till I saw the price,not sure if I want to spend that much for an EFI setup. :G-Dub:

[GregWeld]

It's a proven fact that you don't loose or gain performance between carb or EFI
You gain a lot of other good things going with EFI…

If you want to do it on a budget and just get it done -- go with a carb and the controller…


Once you have that intake manifold etc - you can then switch to a throttle body EFI (a wet system) if you want to down the road.

[71RS/SS396]

I thought about that till I saw the price,not sure if I want to spend that much for an EFI setup. :G-Dub:

I guess it really boils down to what's more important the looks or the performance. While the peak power is really not any different as Greg said, the performance throughout the rpm range is far better with efi. Carbs can only be maximized in a few areas of the rpm range and are only close everywhere else. The fuel around today is not formulated for a carb, there's no anti boiling agents anymore so vapor lock/fuel boiling is a bigger problem than it used to be with a carb.

[GregWeld]

EFI is the ONLY way to go --- for all around performance and drivability….. but it IS expensive to convert… so I get it when people just want to stick with a simple carb and distributor they have. But if you can swing it - EFI all the way.

I have the 8 stack IR set up on my '32 -- and also had it on my '56 Nomad - you could not have started these cars for months… (on battery tenders!) and go out and just reach through the window and turn the ignition and bam! They start up and idle immediately. Can't do that with a carb…

But EFI is far more costly than just switching an intake manifold. The benefits are many… and worth every penny… but they are far more complicated and costly. The new self tune systems out there are pretty straight forward installations and run beautifully and need no dyno time. So if it's just a street car - and you're not trying to get the last .001 at the drag strip - that's the way I'd lean <no pun intended -- LOL>

[hifi875]

After running a carb on my ls for 3 yrs I switched to the Holley terminator. Really does a good job!!!

[GregWeld]

WTF -- It's XMAS --- get all your friends and family to chip in and get you this for your carbureted intake manifold…


http://www.fuelairspark.com/fas/ez-efi-2-0r-self-tuning-engine-control-system-master-in-tank-pump-kithtml/

[71RS/SS396]

EFI is the ONLY way to go --- for all around performance and drivability….. but it IS expensive to convert… so I get it when people just want to stick with a simple carb and distributor they have. But if you can swing it - EFI all the way.

I have the 8 stack IR set up on my '32 -- and also had it on my '56 Nomad - you could not have started these cars for months… (on battery tenders!) and go out and just reach through the window and turn the ignition and bam! They start up and idle immediately. Can't do that with a carb…

But EFI is far more costly than just switching an intake manifold. The benefits are many… and worth every penny… but they are far more complicated and costly. The new self tune systems out there are pretty straight forward installations and run beautifully and need no dyno time. So if it's just a street car - and you're not trying to get the last .001 at the drag strip - that's the way I'd lean <no pun intended -- LOL>
Greg, the cost really depends on if the Op has the factory efi LS intake and throttle body, if he does then there's really no cost savings converting to a carb. The LS carb conversion kit with the intake and igntion box is $700+ and a decent carb will cost $400-$500 which adds up to the same price it would cost to buy the ecu, harness, and pedal from someone like Speartech. Now it won't give you the old school look but to me the overall performance is worth the looks.

[DaleTx]

I am toying with the idea of putting a carb on an LS3. I want to keep some old style look of the carb on my 68 Camaro but don't want to loose any performance from the LS3 either. Any suggestions? :hairpullout:

The big advantage of computer control EFI is that you can run higher compression, and a larger cam as compared to a carb set up... and still maintain good idle and drivability. And like Tim said...the formulation of the fuel is different today, and is designed for EFI engines and does not works as well in carbs.

I went with a single plane intake, port fuel injection, 4-barrel TB, and a GM ECM on my last build. It has the old school look... with all the performance gains of the fuel injection and computer control. GM Performance parts makes a single plane that fits the LS3 heads, and the LS7 heads... so you can run a carb or 4-barrel TB.

Decisions... decisions!

:cheers:

[NOPANTS68]

I've done a couple LS engines with carbs and have had great results. It's super simple and the MSD controller is easier to use than a phone. As far as the fuel changes, hard starting, etc. etc.- I don't know about all of that. In fact, my results say otherwise. My 3200 lb. Nova ran mid 11s all day, any day with a T56 and 3.73s with a used LS1, cam, a 750HP, and hand ported 853s. No big deal, plus it looked awesome and different. I think I'm pretty good with a carb, so it's my preference. Go with what you know, but at the end of the day you can't convince me the EFI looks better than a Victor and a carb. BTW, in most cases LS engines make substantially more peak power than the plastic EFI setups.

[Rod P]

dude if you want it carbed then do it, when I popped the motor on my car, a carb LS made sense, already had a kick azz fuel system and a great carb, so I swapped in the LS dropped on an edelbrock intake and the MSD 6010 box (3 wires to hook up!, power, ground, tach) and I drive my car everywhere with the same fuel system(holley HP Billet 12-890), transmission(t-rex 4 speed), drive-line(8.5-10 bolt with detroit tru-track), everything I had before but now I get 19 miles to the gallon and still kick butt on the track

http://i752.photobucket.com/albums/xx162/crazyshopmonkey/engine%20build/GEDC1515_zpsc3ec9369.jpg

http://i752.photobucket.com/albums/xx162/crazyshopmonkey/2013%20events/scottsdale%202013/GEDC1720_zpsc66e82ad.jpg

[Vince@Meanstreets]

EFI is the ONLY way to go --- for all around performance and drivability….. but it IS expensive to convert… so I get it when people just want to stick with a simple carb and distributor they have. But if you can swing it - EFI all the way.



The way I see it, if you gonna do an LS and have the intake go all the way with it. A PCM program, Walbro pump and a C5 regulator to me is cheaper than a carb ,fuel pump and ignition controller. If your getting a long block with no PCM, Harness or intake then yeah, its the easy route.

[LS1-IROC]

I just don't get the argument for cost when talking carb or EFI. If you shop smart and have some wiring skills you can do EFI for cheap.

[GregWeld]

I just don't get the argument for cost when talking carb or EFI. If you shop smart and have some wiring skills you can do EFI for cheap.



I agree with you -- but you're also making some big assumptions. Most people are fine "mechanically" but when it comes to wiring -- they're nightmares.

So yes - it can be done inexpensively IF you know what you want - and how to put all the parts and pieces together to make the system work. That's usually not the first time guy.