I have a 4bl carb in my '82, and a friend who says I should convert to TBI with megasquirt and then the mechanic I got the car from say TBI is worthless an TPI is to hard to convert. What are ya'll pros and cons. I like the carb but most likely need a new one.

Build a 350 or 383 or better, use a holley 750 carb. I will tune it for you for free. Hell, find one for cheap on Ebay and i will rebuild it for you as long as you dont mind cleaning the parts up, i will build it and tune it for you.

EFI is nice, but for the mony? Not worth it to me. Not to mention, i dont have a choke on mine and there are heads and cam LS1 guys that have a hard cold start compared to me. It is all in the tune. As long as you keep you driving manners normal, they are both going to get decent fuel mileage, the EFI will get a better economy, but the carb will usually make more power.

That is just me, other will tell you EFI all the way.

For me TPI sucks, LT1 EFI sucks, LS1 EFI is cool, but all the EFI stuff costs too much for me to even think about converting.

When i got with a LSx motor, it will have the carb conversion and the MSD box to control the timing with the stock coils.

Hops you make the decision you really will like.

Z

Ok, Should a carb adjust for the temperature. Like if its cold will the choke open more or would I have change it myself ?? and How responsive can a carb be? I have a 305 with the stock 4bbl carb right now and I have to richen the carb myself and once a week it will idle at 2000 rpms instead of like 1000 rpms. If thats not normal then over Christmas or summer (college kid) I will get a new carb. but I'm not sure about dropping the 355 block I have in. Thanks for the offer I will keep it in mind!

Are they responsive? Hell, didnt i take you for a ride when i had the 383 in?

Well, i dont have a choke on any of my cars, but a choke helps, makes cold starts a breeze, but they should not have to be tuned once you get it right.

A carb will not adjust for changes in weather, but is generally rich enough that it won't make any difference.

A perfectly tuined carb will make the same power as a perfectly tuned FI, all other factors being equal. Which is easier to tune depends on personal preference and the exact setup. Carbs don't require as much additional equipment.

FI will almost always give you better mileage.

I switched to FI because it was easier to tune than a carb, but that depends on the type of FI you are using.

TBI is OK, but most will limit you by the CFM of the throttle body. Mine is 900 CFM. I hear that a factory computer on a factory TBI seldom works right on a modded motor.

The megasquirt is a good system, but it takes a while to get get it tuned.

If I were going to set up a megasquirt with TBI, I would look for a couple of factory 500+ CFM 2 barrel throttle body injectors (the ones with the big injectors) and put them on a dual 4-barrel manifold.

i find a lot of people are "afraid" of the efi (aka tpi tbi). a carb is simple. 4 bolts and some linkage and your up and going. there are a couple advantages of having a carb... quick to tune, cheap and there are lots of aftermarket stuff for them... ie intake, and carbs them self. I have an 89 305 and i went for the TPI after throwing out the TBI. the TBI is just a glorified carb but more expensive to replace... otherwise its a bit better fuel economy and a bit more power then the carb which a good eldbrock rpm preformer could take care of that. the TPI is great but a lot of wires... if you already have a carb you will need every thing from ECU to intake and distributor.. and you will also need to put in an electrical fuel pump. it can be complicated if your not that great with wireing.... also the disadvantage is that anything bigger than a 350 the stock TPI wont preform as good. BUT once its running its great... you plug and play and theres no playing and adjusting the injectors... or stoping and tuneing the carb because of elevation changes... its just drive, drive, drive.. also there is a certain satisfaction in standing up (after ripping half your hair out) and saying " i did it!!!!"....


also how do you drive he car also determins what you should be doing to it

Yea, i dont have tons of money so EFI wales too long to get together for me. Rebuild a 60$ used carb and i am ready for 100$.

is somewhat subjective.

That aside, converting up to ANY EFI from a carb'd set-up, is definitely
NOT a low-budget, low-experience project -- which it sounds like you
might be. (No offense intended, all the guru's here started out like that.)

So re-build or upgrade the carb you have, and then other modest
projects like general tune-up, & maybe improve the exhaust system.

Good luck.

I have a full TBI system off of an '89 Chevy 3/4 ton truck, I just dont know if I should, would it improve my mileage or power a whole lot? I don't have a whole lot of $$ so TPI if out of the question, plus my scoop would then have to be attached to my hood. I don't plan on upgrading to a 350, I may just get a new carb and get it well tuned. This is my daily driver so milage is a a big thing to what I decide.

If it were tuned properly for your motor it would improve your mileage. How much depends on how poorly tuned your current setup is, maybe a little maybe a lot. It would not make much difference in power unless your current setup is WAY off.

Chances are, a FI system for another motor would not do you much good unless it were reprogrammed for yours. Just like a carb that ran great on another motor would not do you much good unless it was retuned for your current setup.

If I used TBI I would use megesquirt and program it. It sounds like my best bet for a budget is just to tune my carb or replace and tune. thanks for the input!