ok lately ive been thinking...i was kinda wanting to swap in a 350 carbed motor this summer...probably a GM deluxe...that would end up costing me over 4000$ im sure...could i get the 305 up to 330hp with the help of n2o...im sure i could easily....do you think i could get more power outta the 305 with heads, cam, possibly carb (so i can run a bigger cam) of course subframes, LCA, better tires and stuff like that? ive already put alot of new stuff on the 305 so thats why i was considering keeping it...i also think it would be easier to keep the 305 in there and not have to worry about completely changing everything out...plus wouldnt it sound cool to say you beat someone in a blown 305 oh yeah and to keep this on the subject of TBI do you think it would be hard to get a TBI adapted to a 305 with heads, cam, and everything...im beginning to thinking switching to carb may be easier in the long run because i wont have to mess with chips and ill be replacing the manifold anyways and a carb is about the price of a custom chip...

 

just my $0.02, if you want to get crazy with TBI you should burn your own chips, or otherwise have a friend that does. If you don't have or don't want either, get a carb. If you want to do everything in one swoop and won't be chainging things around all the time, a chip from a guy like Ed Wright or Howell or other well known establishment might be a good idea

 

Yeah, a carb is the same price as keeping TBI initially. Not true if you drive the car more than just a 1/4 mile a year! TBI and EFI tuning equipment will pay for itself in gas money saved!!!
I believe Grumpy said it best when he said... you can't NOT afford to stay with EFI.

 

TBI doesnt do very well on gas compared to TPI or something plus the more you mod the engine the less gas milage you get anyways...since when was gas milage an issue on this forum...i think carb would be much easier just because if i start changing things slowly the cost of chips would kill me...if im gonna replace the manifold anyways and the distributer it wont be that expensive to swap...i know you guys are pro TBI but i might go carb if i decide to keep the 305 if i get a crate 350 im definetly going carb tho

 

i am trying to sell my 454 TB. i am planning on going carb when i get some more things from the bottom of my sig up to the top of it

 

where did you hear all that? my car has always gotten in the 26+mpg range on teh highway and always over 20 around town. that is very good mileage for any V8.
and if mileage is a concern you shoudl not even consider a carb at all. they are easy to tune and stuff, but they don't get good mileage. also, why change the distributor? you shoudl do what pablo did na dleave the electronic advance and everything plugged in so you can still do soem chip tuning.
the cheapest thing you can do is always working with what you already have. the tbi can do a lot of compensating on it's own and still maintain excellant mileage and drivablility. even after i added heads, intake, 1.6 rockers, and gears i got 26mpg on the highway without the benfit of the toque convertor locking up. that was also without any custom tuning, stock chip, letting the ecm compensate for itself.

later
tim

 

bad gas milage could be because of a bad 02 sensor I've heard.

 

i am not into the gas mileage game i drive well under 100 miles per week sometimes and this is a daily driver. it usually never sees more then a few miles of highway. bottom line for me is that IMO easiest/quickest way to get the car running to top potential after major mods is carb

 

Top potential is a joke. Carb isn't that easy and if it were there would be no need for EFI since potential means you're getting the MOST out of the engine with the LEAST amount of fuel. A carb is very inaccurate. Just the slightest weather conditions will change how the car responds, a good efi system doesn't have any of those problems.
I don't feel like doing the math again but you can easily figure out what money you'd save by keeping EFI.
Reason why I kept EFI: Better drivability in ALL weather conditions, more control of the tuning, computer controled timing (a big help), o2 sensor and closed loop to save me money.
Costs to go to a carb: You need a carb (duh), a mechanical dissy if you scrap the ecm and don't bother to rig the TPS up to the carb linkage, and a new fuel pump and/or a fuel pressure regulator.
Costs to keep EFI: Tuning equipment costs ~$300, wow, that's it . Larger injectors might be needed depending on your application and you might need to make or buy an adaptor plate.
If I drove only 8000 miles in a year, used EFI and got an average of 22mpg and the cost of gas was $1.40, I'd have spent ~$500. If I used a carb and got an average of 16 mpg, that's $700. I just saved $200 in just one year driving my car on 94 octane. That more than justifies keeping EFI. Carbs might be easier to tune but that's only because it isn't common practice for people to tune their EFI systems. Give it a couple more years and you'll start to see a lot more custom EFI tuning in the hot rod world. It's never been easier to start burning your own eproms. This site is full of some of the best information regarding custom eproms and there is even more over at www.diy-efi.org

 

nope trying to get the most out of a modified engine i can with a stock chip and some more fuel pressure and base timing is a joke

 

exactly i cant wait a couple years for joe blows shop down the street to dyno-tune my car. just ask ya this jon, how many custom chips have you burned for your car and is there a "better" one you havent got yet? and if i cant tune a carb there are about 10 guys that will do it for me for FREE. i understand weather conditions might fluncuate a lot up north but down here we only got hot and slightly cool

 

At this point I don't give a **** what people do. People that don't have the hotrod desire to play and tune theire vehicle are rare now adays. The only difference between tuning a carb and EFI is one uses hand tools and the other uses a computer with VISUAL GRAPHICS that make everything so easy.
I try my hardest to get people into eprom burning and why do you think I do that? For my own benifit...HA, it's because I hate seeing people go backwards.
There are a lot of guys that go to carb and few that stay with EFI, ask ANY of the guys that do their own eprom burning and see if they will ever drive a carbed car. Ask them if it was worth their time and money! $300 can definatly go to a nice carb which is more flexable but you will NOT get the full potential out of any engine with a carb compared to EFI. Just look at all forms of racing that allow EFI, they all use it because they make the most power AND get great gas milage, it's a win win situation and the only racing that uses carbs anymore are those that have rules which mandate carb only. Not to mention, if you want to tune a carb, it's a LOT easier when you've tuned with EFI. It's all about how much control you want over the operation of your vehicle. With EFI you can modify anything and everything, you're the boss, with a carb you set it up and let the engine/weather dictate how it wants to run and their aren't any fine adjustments like timing retard when an auto shifts, or when the tcc locks, or when you smash the pedal to the floor and don't want ANY hesitation...only with EFI. Carbs can be tuned for WOT performance in a hour but EFI can do that and much more with a smoother operation, better gas milage and a flatter torque curve (in most cases).
Computers are the future, why does everybody want to ignore this?
To sum it all up, get a carb if you don't want to learn how to get the most out of your engine and if you don't mind it costing you more in the long run. Stay with EFI if you want the best for your car and do NOT use a stock eprom with a modified engine, it isn't fun and it gives speed density EFI a bad name!

 

how can you get top end power with the tiny TBI bores?? look at a carb it can take in so much more air and you have a huge selection of manifolds, n2o systems (only one system i know of specifically for TBI), parts are easy to find, and ive been looking at posts and it seems like everyone that switched from TBI to carb is very happy...

 

I'm going to reply backwards to your last post. Everyone that switched from TBI to carb is very happy because they didn't know jack about TBI. Carb was great because they could tune the fuel system and timing...but that's now possible with TBI just as much as it is with TPI! The problem with TBI is just like you said, the aftermarket didn't pickup on performance parts because TBI was never placed on a performance oriented engine. TBI got the bad wrap from the factory when they used swirl port heads and a wimpy cam compared to the TPI versions. There isn't a lot similar with a stock LB9 vs a L03 and the L98 comes with better heads than the L05, and the L05 makes less power than the $1300 goodwrench motor :shakes head:.
Now for the scary reality, TBI has MORE options as far as intake manifolds and N20 systems are concerned. Actually the number of N2o systems for carbs and TBI is dead equal.
TBI can be adapted to any intake manifold with a very simple adaptor plate. It isn't fancy, it's really easy to make so long as you've got a couple tools like a tap and a way to cut out a bore for the TB! So TBI has more options than carbs now that TBI can use the specific TBI intakes and ALL square AND spread bore intake manifolds including crazy big single planes.
Oh yeah, and the TBI fuel pressure is a free mod that might cost $5.00 for new gaskets, that's pretty nice that you can change "jets" with just a screw on the fuel pressure don't you think?
Now let's talk about N2o kits. Yeah, there is only 1 TBI specific plate system but it uses the same solenoids and bars as the carb kits. Now if you go back and notice the adaptor plate...what says you can't use a carb kit? Oh yeah, and if you had the eprom burning equipment you could take out some timing under WOT (yes, only under WOT) to make sure you don't blow up your motor! The reason I said the number of kits was a tie was because the carbs have that new system that sits on top of the carb on the air cleaner stud. TBI can't use that so it's dead even but the flexibility of TBI when you get into eprom tuning is unreal. BTW, the eprom doesn't just control timing advance vs engine rpm and vacuum. It also changes depending on coolant temp, intake air temp, power enrichment mode, and many other conditions. TBI also emulates the carb accel/pump shot to prevent hesitation from the fuel condensing on the intake runner walls from the sudden change in manifold pressure! So if you think about it, TBI has 2 problems. One is that darn restrictive injector pod which just so happens to not matter when using a perimeter style air cleaner like an open element. The stock intake is stupid and restrictive because it forces the air to go around the injectors. If you use a spacer to make sure the drop base doesn't rest on the ign. coil then you can junk the spacer ring. I'll take pictures tomorrow of what I did to get the open element to fit on my setup. It cost me $15 for the drop base air cleaner and that's IT. Everything else I did was just some tinker time, probably a half hour now that I figured exactly what needs to be done (when and if you have hood clearance issues).
Oh yeah, and my 1/4 performance was running WAY rich (cranked fuel pressure down), a few fuel adjustments and NO timing map tweaking! It was a legit 13.8 at 102 with basically a stock ANLU (cop car L05 eprom). A lot has changed since then and I hope to have time to run my car over spring break with a stock ANLU bin and my stock 305 L03 eprom to show the difference.
If you want to look at the flip side, go watch my motor under a completely stock speed density TPI system with the 7730 ecm. Give him stock fuel pressure and injectors and my motor and I'll bet you'll have the same problems.
I almost forgot, TBI isn't limited to just 2 barrels, you can actually have the stock GM ecm control a 4 barrel system if you built or have somebody build an extra injector driver board (it isn't expensive). I plan on making a few when I do end up going with a 4 barrel 750 or 900 cfm Holley pro-jection TB.

 

Just some food for thought.
I think that when we dream of big power gains we often focus on the peak power as if all we are going to do is race. Years ago I ran a big cam with a well tuned carb and its a blast every time you you run through the gears(I had a 4 speed super T10 and 3:73 gears). BUT, IT MAKES A PRETTY PORE DAILY DRIVER, especially in town driving. When these carb guys say there car runs great, I feal they are talking about how it runs through the gears.I want to be able to lunch hard from a light and then sit at the next light at a idle with my AC on and not have to drive with both feet to keep it running.
In my opinion, carb is a compromise.

Look real close at how you really use your car, and then decide if you want to give up driveability and dependability for peak power.

Peace, (not flames)

 

id go with a holley TBI or something but would i need it with a 305 even with heads,intake, cam and n2o? im sure it wouldnt hurt. Im still not sure what i wanna do but if i buy a crate motor more than likely the TBI will go but if i decide to keep the 305 for some reason it will probably keep the TBI. im just wondering if i can get the same performance out of a decent crate motor that i can with a modded 305...it would take alot of money to pull 330 hp out of a 305 like even the weakest crate motors have for 3199$. how much HP do you think the 305 would be putting out with 305 torquer heads, lt1 cam, edelbrock TBI intake? this being with custom proms and everything...then id like to see if she would hold a 100 shot of n2o...

 

i think you just perfectly summed up the world of carbs.
they work great for an application adn are easy to tune with in that application. but for all around EFI is the way to go.
how much power are you looking to build otu of the 305? if you are plannign to do a 350 swap you shoudl just do teh simple stuff to your 305 and worry about the big parts for the 350. that will keep your 350 budget from getting eaten up by the 305 and ultimately get the new motor in hte car sooner.
a 670 holley can support a 305 or 350, it can be easily adapted to both. if you wanna get it now, get the 350injector one and turn the FP down(it has an adjustable regulator from teh factory)

later
tim

 

im only looking for about 350ish hp with n2o...i know i can get that out of a 305 easy

 

J, where are you running? Im gonna be at Dragway 42 once or twice over break (ours is the same time as yours... 22nd till the 2nd). Or will you be back in P-town?

 

I have no idea where Dragway 42 is, I only know of National Trails raceway off of Rt. 70. I wouldn't mind doing a road trip before I go back home. Last final is on he 19th, e-mail me.