looks look im in a position to either go back with fuel injection or carburated. could you give me a brief run down of the pros and cons of this and how doable the carb would be. seems the carb could be a lot less hassle if the motor is not stock as far as tuneing.

 

Street car or Race car?

 

I was thinking the same thign a while back. I am a diehard carb guy. But I chose to stick with the injection.

 

well sometimes both but not at the track for the most part. im not worried about emission or fuel mileage.

 

i decided to take my 90 L-98 carburated. In making that decision i did a serch on carb here on the forum and read all the threads. you may find that useful to do as I did. I will only be driving my car in the summer and do intend to drag it. what clicked for me was that i save money and get my car on the road again.

 

when you get a chance could you run down your parts list and some problems you may have encountered. like what intake and gasket. what should i expect from the computer as far dash lights and compatiabilty. will the ecm just flash codes for the missing sensors? what about timing? what set up did you use as far as fuel delivery?

 

Assuming you don't have to smog test your car there in TX, a carb is the simplest setup. You will lose the functioality of the dash "center" displays. You will also lose the high efficiency of the fuel injection setup...a big consideration if gas cost has gone up where you live. At idle the GM ECM actually leans out the A/F to 16:1 at times! Of course at WOT it chunks it up to a nice 12-13:1. I have read from the legendary Smokey Yunick that when you design the perfect FI system that you basically would end up with a carb!

 

Injection all the way if you plan on running this thing on the street. I have had both on C4's and can tell you a fuel injection system is the way to go for a daily driver

Carb
Pro's -
Easy to trouble shoot and requires no electronics other then the distributor
WOT tuning is a breeze and it will make great power
Cons-
You will have to buy everything needed for this install
Hood clearance is close and a bit of a PITA
Your tune for fuel and jetting is the same for all conditions across the RPM range (If you need a little extra fuel between 2000-3000 RPM and a little less 4-5K tough)
Your ignition timing is the same boat you can tune the man advance via weights and the vacuum advance and that’s it.
Knock retard the old fashion way turn the distributor no ECM to take care of a little bad gas here.
Gas mileage, I know you may not care but I do get 26-27MPG Hwy with a 400+RWHP/RWTQ motor running well into the 11's.
Probably not a big deal but your MPG gauge will no longer work.
If you have an auto you will need a way to lock up the converter (I used a BTO kit for $80)

FI
Pros
Tuning across the board for both fuel and ignition
ECM controlled knock retard; a little bad gas will be handled w/o a problem
Good fuel mileage
Will still pass emissions if it is ever needed
Cons,
Can be a huge PITA to trouble shoot at times
More parts to break (Sensors, injectors, ECM, wiring etc...)
Will limit performance with the stock TPI and after market intakes are not cheap

A short parts list for the carb conversion
intake (Low profile)
Carb
T fitting for fuel line
fuel regulator for a carb (Hooks between the feed line and the return line with the T)
Distributor
air cleaner (low profile)
That is all i can think of off the top of my head

 

 

ok i can live with all that. my only question is about the distributor. will my new msd fbody conversion with external coil not work with this set up? i have a couple of friends and an uncle that know sbc carbed as they have race cars. so im not affraid to dive in. with the modified l98 odb1 i have no way to tune it other than shipping back n forth an eeprom every time there is a problem or upgrade. it just makeing more sense for me to go carbed or go back to stock then it will all work perfect while i watch my ole ladies honda mini van pull away. not happening.

 

are we eating popcorn for the efi or the carbed? or for this whole debate again?

 

oh yea nice hang time is that car yours? if so what intake do you have on it?

 

I have no idea of what distributor you have but if it is a ECM controlled one then no it will not work, no ECM. As far as the tuning goes what problems would you have after the thing was tuned? I do some of my own tuning and can't see why you would touch it after the tune is correct but hey if you want to use a carb then ok but there are plenty of reasonable tuners that do great work such as PCM for less that should be able to get your tune just about dead on so don't let that be the only reason.

 

so ecm controlled hei will not work? seems my for sale list is gone be worth more than my to buy list. na tuning is not the only reason i can think of. but if i lived next door to a tuner that would help

 

A friend of mine has put a carb on his IROC and has had nothing but trouble getting it all working correctly. His biggest issue is with the tuning and getting it all ironed out. While in theory it is "easier" to tune a carb you have to have a huge assortment of jets and you have to take things apart, etc, etc. It's not a problem if you have money and time, but both of which are things that my friend is typically short of.

My friend also has timing troubles as well so you're never sure if the problem is in the distributor, in the carb, a combination of both, etc. Add this to the fact that given a specific problem / complaint there could be any number of causes and it just works out to be a major headache.

Fuel injection is harder to install initially and it does require a lot more wiring / sensors, etc. However once you're done you can data log the car. You KNOW where the timing is and you KNOW what the fuel is doing. There is no more guess work and you can tune the car without getting your hands dirty. You can also have performance AND fuel economy that can be very hard to match with a carb.

 

Yes. I am doing the carb conversion this week and next. I expect to use a demon carb, ill get the p/n later. A low profile air cleaner, and a Edelbrock air gap intake manifold. Ill be using a Mallory pressure regulator and a return line for the carb, using the stock in take fuel pump. I have auto transmission, so you need a step down (?) linkage on the carb. Same set up as on my 383 Camaro with AT. Just tie up the harness out of the way. This is all info i gleaned from prior threads on this matter.

You have a little over 9 inches, so ive read, between the engine block and the hood.

In the future, i will add a Weiand Roots blower and pop a hole in the hood. Cheap (approx $2K) and easier to fit SC than trying to use FI and a SC, I'm thinking.

I guess i wouldnt do this but for 1. i intend to save money by NOT pursuing FI on a modded car, 2. I will get my car done sooner, 3. it is not a DD 4. The SC route should be easier. 5. I pick up some money by selling my FI parts.

Im sure FI is superior, except in relative initial cost to those with moded engines like mine.

I will post p/n, issues, etc. when the project is done for those who are interested.

 

One idea if your having a hard time with the EFI tuning or plan on changing your setup often is to have a on site chip burner.

They run about $80 and along with a datalogging cable a tuner can get the car tune in pretty much the entire way via email.

 

thanks, but i think ill try the carbed vision this time around. will who ever has done this let me know what parts they used.( intake, carb, distributor ). thanks

 

I have done this and if you have an auto (700R4) you will need a little more then the standard linkage you are thinking or you wil be purchasing a new trany in a short while. You need two things 1. a proper TV linkage (This normaly requires an off set plate for most carbs) and 2. a way to lock up the converter. Once your ECM is gone (and you have tied the wires out of the way as you said) your trany has no way of locking up the TC and will burn it to the grund in short order.
Now for the good news BTW makes both of them

TV kit just choose the carb for the proper kit.
http://www.tvmadeez.com/

Lock up kit

http://www.bowtieoverdrives.com/cata...SUBCAT&CATID=O

Here is the old 84 with the carb

 

mine is a 6speed