Quick Question

[JacobS]

I'm working on putting a 5.3 LS engine into the nova. I was thinking about going carb for the simplicity. I for one am not good at wiring, nor do i care to learn how to do my harness. Just curious what other peoples thoughts are on the subject. EFI vs Carb, Pros and Cons, shout them out!

The car will be a weekend driver, with a mild cam and maybe a little bit of nitrous.

[86svo9L]

Carb is always fun. It is simple and easy to maintain. MSD has a nice piece you can plug in to fire the coils in standalone mode.

Honestly though the EFI is so easy to get working its hardly worth passing up. You are already going to have to run an electric fuel pump and all that good stuff.

[StreetSweeper]

I'm using the MSD 6ls 6010 box been playing with the software it's prety stupid proof!
if you were going to boost it efi if ur just looking for motor or spray carb is simple and easy and will make just as much hp if not more then efi. Assuming you have a properly set up and tuned carb.

[AutoMods]

post up your parts list and prices for the carb conversion vs efi.

-minor but I forgot you'd have to also buy a $50-75 e-fan controller without the factory computer
-does you nova need a new fuel pump either way? is your pump internal?
-need an aftermarket fpr either way?
-can you easily convert the carb to e85 if you want to ?

[StreetSweeper]

You would need a carb manifold, msd, and carb , everything else u need reguardless. Why does he need e85 for a simple cam only set up?

[8204Cobra]

Because Ryan thinks everything should be on e-85

I agree weigh your options with a list

Just throwing it out there if you want to run carb for now size your lines and set your tank up for efi now and when and if your ever ready it would be that much easier for the conversion, and you can always sell your carb manifold or have it modified to accept injectors.

Plus in my opinion it would be something a little different to see a Carb'd setup on an LS motor at cruise night, and they just have a little different sound to them and your not as limited much to cam profiles if you didn't care about efi

Not that its a huge deal with availability in the aftermarket what trans are you going to run? Are you going to need a mechanical speedo drive?

Do you have a wiring harness and computer?

Whats your plan for the car in 2 or 5 years as far as power adder?

How much MPG are you going to really gain going efi? vs. just spending an extra few dollars for gas

[JacobS]

the car currrently has a th350 trans. i do have a harness and computer.

in the next couple years, i cant forsee any big changes happening to the car. unless of course i win the lottery. I would probably be happy with it with a cam and a little nitrous, maybe build the motor and get a better rear end. but nothing to crazy

[Scott]

Everything is easier with a carb IMO, specially if you start having issues. If for whatever reason you want to run E85 they make carb's for that same price as a gasoline, methanol, E98, whatever or you can convert your existing one. I think they look a hell of alot cooler, better flowing intake system, put whatever heads, cam, exhaust you want on it whenever you want and tell the laptop to screw off, dont worry about "running out of fuel" and having to buy new injectors.

The 347 my dad built and put in his 65 has a out of box stock prosystems carb and that thing runs better and has better throttle response than most EFI cars of the same caliber I have driven.

Or be a girl and put EFI on it so you can brag about how good it starts in the winter time without touching the gas pedal

[Drifte]

I'd say carb. It suits that car, and you guys never drive it, and certainly not in the winter. Although EFI in that would be kinda cool. Sounds like the type of car you throw a cam in for the sound, but need the hp for burnouts after car shows too.

[snickerlicker]

Leave the carbs in the trash can where they belong.

[AutoMods]

Or be a girl and put EFI on it

i wouldn't mind jacob going carb, it'd be interesting to drive it, tune it, compare it to the other efi LS motors i've been in

i sure do like the laptop though. keeps my fingernails clean and you know that gas smell never washers off your hands with the first try

http://img105.imageshack.us/img105/6184/dashboardan1.jpg

[Scott]

keeps my fingernails clean and you know that gas smell never washers off your hands with the first try



Men are supposed to have a little dirt under their finger nails and smell like gas from time to time, I guess it would be alot easier for the foofoo starbucks crowd to use the laptop so you dont wash the lotion off your hands! I say if you dont want to work on your car at all then you wouldnt be in this forum in the first place.

Obviously EFI has its place, I just dont believe its worth the hassle all the time, being a engineer and working around this type of stuff all day has taught me how important the KISS principal really is. on a side note I havent changed a carb jet in my car or my dads car in years, so if your thinking a carb is high maintenance item I would have to disagree, you will probably be changing timing more than anything and that is done with a laptop anyway. lol

[SledgeWS6]

Men are supposed to have a little dirt under their finger nails and smell like gas from time to time, I guess it would be alot easier for the foofoo starbucks crowd to use the laptop so you dont wash the lotion off your hands! I say if you dont want to work on your car at all then you wouldnt be in this forum in the first place.

You forgot about the smell of cow shit and chew stains on your jeans. /trolling done

[JacobS]

this is what i have so far for a parts list with some rough pricing

EFI:
Convert to drive by cable $200?
Fuel Pump $100
FPR $100?
Random fitings/line for return style fuel system $200?
Electric Fan/s $100?
Modify harness $75
cheap mail order tune $200?

$975

Carb:
Intake manifold with timing control box $770
Fuel Pump $100
Electric Fan/s $100?

$970



anything else im missing please chime in on either one.

[Fire Hawk]

EFI can be used either with drive by wire or drive by cable. Just need to figure out what you already have and would need to make it work.

[AutoMods]

mail order tunes are $75-$100. I don't know how they offer it but some also do unlimited changes for that price. you just pay for shipping. but you can pay $100 to register your vin with my efilive controller and I will flash your computer for you.

do you get a drive by wire throttle body with your motor?
what carb does your nova have? how much do you need to spend on it, rebuild and buy a jet kit?

[JacobS]

yea, it came with a dbw throttle body. currently have an edelbrock 750cfm carb, probably wouldnt NEED a rebuild, but id probably do it anyway

[slow ride]

EFI is going to get better mpg since it's constantly fighting to keep things at stoichiometric under closed loop conditions. EFI is simple in this case and the ECU will tell you whats wrong most of the time or point you in the general direction. The EFI manifold will probably have a better powerband under the curve depending on what carb manifold you were looking at. The EFI intake from the trucks do look like poop though. Get the car tuned, run the wiring well isolated from heat, etc. and never open the hood again no matter the weather conditions, etc. I'd say the factory wiring and electronics are going to be way more reliable than a junk MSD add on box over the long haul.

I've see carbs outperform many a EFI setups at the track or dyno, but it wasn't due to one being better than the other. You guys sell the crap so dig in and get a better understanding of whats going on. Ryan is right there to look at the ECU with you, etc.

[StreetSweeper]

Cant wait to whoop your azz ryan with My carbed JUNK! lol Sloride you can get in line for after im done with ryan to. lol

No but honestly if m car was EFI for ls from he start I would be using it. For my power adder and simplicity of the swap carb it is for this guy!

[Deimos]

yea, it came with a dbw throttle body. currently have an edelbrock 750cfm carb, probably wouldnt NEED a rebuild, but id probably do it anyway

price out tha throttle body then selli on cragslis now is the time being as the col weater will cuase the electroic actuatorsnot to move frey.

[SLVR7]

price out tha throttle body then selli on cragslis now is the time being as the col weater will cuase the electroic actuatorsnot to move frey.

Well it looks like a craigslist ad,lol

[snickerlicker]

price out tha throttle body then selli on cragslis now is the time being as the col weater will cuase the electroic actuatorsnot to move frey.

Deimos been in the sauce? Lol

[Deimos]

Deimos been in the sauce? Lol

Fat fingers and lack of sleep if he cat understand me by now he never will

[skipdownstairs]

Leave the carbs in the trash can where they belong.
I think the carb set up was a pretty reliable piece with the MSD box and Eldelbrock intake. Don't buy the kit from jegs or summit as it is way more money and you dont have control of the maps or nitrous controls and 2 step via laptop with the Eldelbrock ignition box snce it is locked out. Here are the part numbers of the 2 parts we tried and dynoed. As far as the fuel injection goes im sure theres some guys on here that can give some good input. Good luck man


http://www.jegs.com/i/Edelbrock/350/29085/10002/-1?CAWELAID=1710598565&catargetid=1784156432&cadevice=c&&cagpspn=pla&gclid=CM6Lm7HYl7wCFc5DMgodyyAAlQ
http://www.jegs.com/i/MSD+Ignition/121/6010/10002/-1

[JacobS]

does the MSD box look at knock and pull timing accordingly? or how would that work?

[skipdownstairs]

No it doesn't they have different tables that come on chips that you can put in or you can make your own timing table. I wouldn't worry about the knock if your conservative on timing. Ecu controlled engines run differently which use as much timing as they can checking from 2 timing tables one low octane and one high octane that's where knock sensors are used. In a street rod application this isn't necessary.

[JacobS]

that answered my question perfectly, thanks

[AutoMods]

LS Motor: knock knock

MSD box: who's there?

LS Motor: knock knock KNOCK KNOCK KNOCK

MSD box: ????????

LS Motor: boom

[DustinsDuster]

my .02: it's going to be a toy. Carburetors are cheap and easy, and you can change them whenever you want. if the car will pretty much only see weekend cruising in warm weather, who cares about gas mileage or cold starting? to be fair, this is assuming you really don't want to tackle the wiring, and the car will be more a toy than a driver. if either of those isn't true, might want to stick with FI.

[JacobS]

both of those are true actually lol

[StreetSweeper]

The pro data software is so easy to use even I can do it. I don't even have motor in car yet and I already made my first map.

[Domestic Disturbance]

I'd stick with EFI. Carbs are great if you have the know how and understanding behind them, but can also be a hassle. EFI you can go out, start it up regardless of temperature, and party. And why sacrifice mileage? Good mpg's arent a bad thing. If you are going for something you will drive a lot and race sometimes why go carbed? The biggest expense you are overlooking is tuning for efi. If you run a stock computer and do some serious mods such as a bigger cam, some nicer heads, etc, you will have $500 into a nice dyno tune setup. You could skip the MAF and go to an SD tune which I think is $600 baseline tune at speed inc. Thats all relative if you get some aftermarket setup.

[Scott]

LS Motor: knock knock

MSD box: who's there?

LS Motor: knock knock KNOCK KNOCK KNOCK

MSD box: ????????

LS Motor: boom

Why would anyway put enough timing into a base tune to cause pre-ignition in the first place? Maybe thats the nice thing about a carb setup is that the computer wont try to add timing to it.. Some of the most advanced EMS do not use knock sensors in the first place. I have no experience tuning EFI cars with knock sensors but its my understanding that even a perfectly healthy well tuned car making good power will show knock anyway

[AutoMods]

Why would anyway put enough timing into a base tune to cause pre-ignition in the first place? Maybe thats the nice thing about a carb setup is that the computer wont try to add timing to it.. Some of the most advanced EMS do not use knock sensors in the first place. I have no experience tuning EFI cars with knock sensors but its my understanding that even a perfectly healthy well tuned car making good power will show knock anyway

because when it doesn't knock you will have more timing and power. if gm tuned for the worst case scenerio of high heat and/or crappy gas, all the cars would ship with ultra conservative timing tables. instead the computer can adapt and keep timing high but still have a safety mechanism to pull timing during knock. the computer also predicts and prevents knock under certain load conditions and has knock recovery settings to slowing add timing back in after a knock event. all the tables can be altered and turned off/ignored if desired but you can still view and log it. its one of the most common things i look at in my logs. i'll see a decent amount of knock when i go to pump gas but with e85 knock is virtually non-existent

its nice to have safety measures built in like the computer pulling timing due to knock or due to high coolant temps or high intake temps. my computer pulls timing for high intake temps too, very important on a non-intercooled car. but most of the time the temps are under control and i'm left with great timing.

if you know what you're doing and run race gas all the time or pull spark plugs all the time, then you obviously need less safety measures. but if i want to shut all that stuff off or ignore it I can.

[Scott]

If your tune is trying to run on the edge of meltdown everytime you step your foot down on the highway you got bigger issues than whether or not you have a knock sensor IMO.

If its so important how come most aftermarket ECM's dont use that for tuning?

[Scott]

Sorry about the pissing match, I see both sides and we can argue forever.. I say keep it simple, make power and make it look cool cheap, put a carb on it. Then put a knock sensor on it so Ryan's happy

[StreetSweeper]

Is he going turbo or driving this in the winter months in Colorado? Or did I miss something here?

[skipdownstairs]

The pro data software is so easy to use even I can do it. I don't even have motor in car yet and I already made my first map.

It is pretty sweet. We did one on that 5.3 we dynoed

[AutoMods]

Is he going turbo or driving this in the winter months in Colorado? Or did I miss something here?

just discussing pro's and cons of efi vs carb. i was kinda moving into general ideas instead of just jacob's setup. although he will be spraying nitrous on pump gas.

not saying knock is a deal breaker, just one more benefit to going the efi route imo. as to why some stand alone's don't have knock sensors, here is what my GUESS would be
1. added cost to implement it
2. some engines with some setups make too much noise at certain frequencies creating false knock. aggressive valvetrain, open headers, etc.
3. they are geared toward the elite guys who are usually more knowledgeable, careful and running good fuel and reading plugs

that said, aem ems has knock control, looks like holley efi does, proefi does. haltech and big stuff 3 do not for the most part, although i did find some guys adding it http://ls1tech.com/forums/pcm-diagnostics-tuning/330295-bs3-knock-control-you-bet-cha.html#post2998017

[JustinS]

Go carb and quit being a pussy.

[Deimos]

Sorry about the pissing match, I see both sides and we can argue forever.. I say keep it simple, make power and make it look cool cheap, put a carb on it. Then put a knock sensor on it so Ryan's happy

This ^^^^ But remember it comes with two on it already. I would change the throttle body trim the harness and go out and enjoy that bitch.

[skipdownstairs]

Another thing which needs to be checked is Top Dead Center and mark it on the balancer so it can be referenced with a timing light just to double check if it says 0* in the msd box it should say it on the balancer with a timing light. The problem with LS engines they have no marks on the balancer since there isn't a keyway on the end of the crank so you have to just mark it somewhere and use a springy piece of #9 wire sharpened to a point to use as a pointer the engine we dynoed using the stock pickup on a stock crank 24x wheel was 2.5 degrees retarded. I would hate to have not checked it and found it to be 2.5 degrees advanced with a 36* full timing set up in the box which in reality would be 38.5* this is really important if your going to spray nitrous on it. There are ways of checking this with a positive stop and a tape measure which I'm not going to get into.

[StreetSweeper]

Another thing which needs to be checked is Top Dead Center and mark it on the balancer so it can be referenced with a timing light just to double check if it says 0* in the msd box it should say it on the balancer with a timing light. The problem with LS engines they have no marks on the balancer since there isn't a keyway on the end of the crank so you have to just mark it somewhere and use a springy piece of #9 wire sharpened to a point to use as a pointer the engine we dynoed using the stock pickup on a stock crank 24x wheel was 2.5 degrees retarded. I would hate to have not checked it and found it to be 2.5 degrees advanced with a 36* full timing set up in the box which in reality would be 38.5* this is really important if your going to spray nitrous on it. There are ways of checking this with a positive stop and a tape measure which I'm not going to get into.

Or run a under driven balancer with marks !

[slow ride]

Crank is not keyed though so the balancer always ends up in a different spot. If you pin it with a forward pin you will never reuse the same location so an ATI sidways type pinning is used to act like a keyway. Most of the aftermarket cranks are keyed now for an aftermarket balancer which is nice.