Belstain

I have a 1990 firebird 305 with tbi bone stock. I'm looking for 350-400hp What is the cheapest way to get that? I'll probably swap in a 350. Will the stock TBI support that much HP? If not then how much mod is needed?
I don't mind investing a few bills to burn my own proms I just want to make sure that is really what I want to do first. would it be easier to change to carb?
There are two ways I'm looking at doing this:
1. If I decide to keep the TBI setup I'll mod that first then when ready do the engine swap.
2. Or if I decide to go with carbs I'll build the engine from the bottom up on a stand then swap everything all at once.
Which way do you think is the easiest/cheapest to get that power level?


How much power can be had with the current engine without spending too much money? Would it be worthwhile to just build up the 305?

firbird

carb is cheeper and easyer

NJ SPEEDER

tbi can easily support those power levels. upgrades for injectors and tb will be needed and definately custom tuning.
the rest of engine woudl be assembled selecting cam/heads/intake like any motor for that power level, teh injection woudl jsut sit on top instead of a carb.
a carb will not save much effort, actually tuning in fuel injection is usually faster and much more accurate. and since you can use the stock ecm and wiring harness, a carb will not even save you much, if any money at all.

later
tim

Pablo

iTrader: (1)

a carb wouldbe easiest and fastest. Youd be forging ahead in unknown territory for the most part if you managed to squeeze that kind of power out of a gm tbi. That means you'll be doing alot of figuring out, lots of testing and tuning, and lots of tweaking to get it where you want it.
I think there are realistically only a few people on this message board who could, would, and should try that sort of thing. I think most of us just want a fast car not quirky science projects.

AJ_92RS

Dewey316

http://www.holley.com/HiOctn/ProdLin...B/950-24S.html

But of course , a carb would be cheaper.

NJ SPEEDER

i don't see how much easier a carb woudl be. fuel injection has all the sensors to tell you what adjustments to make and he already has it in [place. it does not take any special engine build up or anything, teh motor itself woudl eb the same.
i worked with carbs for years, and i know that with in a few mins you can gt them performing good. but to get to teh next level it requires a lot fo runs or dyno time. with tbi it has been proven by several peopel that a few mins of data logging on the street will lead to excellant performance very quickly.
also, with a carb you are limiting yourself to mechanical timing. that is a huge limitation on performance.

later
tim

Belstain

There seems to be a bit of a dispute about how much power these systems are capable of supporting. I don't understand why it wouldn't be able to support that much power. What is the limiting factor? Air, fuel, or the computer? you can get bigger injectors to handle the fuel flow. the computer can be upgraded to deal with that. How much do these systems flow? how much can they be made to flow? and can you get aftermarket ones that will work better?


If 400hp isn't realistic then what is?

NJ SPEEDER

400 hp is not a lot to put out at the crank. it can easily be supported by tbi by upgrading teh tb and injectors. the computer can easily be set to compensate for anything.

later
tim

AJ_92RS

If you've worked with carbs, then you should know how much cheaper it is. And after all, that's what we're talking about. Not how much easier.

IMO, it is easier. A lot easier. Carbs are self adjusting (to a point) just like a TBI is. The more air that gets pulled through, the more fuel that goes with it. If there isn't enough fuel there, you just increase your jet size (no different that adding larger injectors). If there isn't enough air, then you have to increase your carb size (which is no different that buying a larger TBI).

It takes me about 5 minutes to change jets, about 1 minute to set idle speed, and a whole 5 minutes to change springs on a mechanical dist. And all I need are a few $2 screwdrivers to do it. Last I checked, and entire jet kit is about $30-$40, and that will cover any combo you can think of. New springs for the mech weights are $10-$15. So know we're up to $56 and I can adjust just as well as you can with $300 worth of computer stuff, and what's the cost of injectors?? I'm gonna guess about $100 ea?

What's a 750cfm @ 1.5"/Hg carb cost? ~$250 w/elec. choke

What's a 670cfm @ 3.0"/Hg TBI cost? ~$320 (which is just short of matching a 500cfm carb @1.5"/Hg)

We can go on and on..... but the fact remains... that HP/$..... a carb wins.

brodyscamaro

the best at GM spends 1000s of hours to get programming right. try having 400 HP, gonna take you a LONG time for the average joe blow (or anybody) to get the tuning real real good (or just good). CARB!

TBI305Camaro

Yeah carb is easier and cheaper. Im happy with my swap. I had a few bugs in my system but all is good now. I think carb drives better, idles better, and makes more power than TBI did. And yes I had TBI.

Like mentioned above carb flows better and is cheaper.

Fuel injection has its finer points but if I was gonna have fuel injection it would be TPI or EFI (ford). Those are much more precise forms of fuel injection. But very pricey.

JPrevost

Most of the owners of TBI don't know how good they've got it. The ecm is completely hacked, $140 worth of equipment is all you need to read/backup, erase, edit, and burn new eproms.
I'll give carbs props where it's got an advantage, but cost is not one of them. First off a 750cfm carb on a Lo3 calls for a (not saying that's what was implied but read on). The biggest mistake with the "doesn't feel fast" is that there is some sort of air restriction so they put on a bigger carb. Not smart especially if you have to keep a high enough air velocity for a smooth idle/light throttle. Then they go to a double pumper to solve their big carb issues. What I'm getting at is how huge cfm numbers don't always mean big power. Also TPI/MPFI isn't exactly great for fuel accuracy. It's definatly a step in the right direction but I wouldn't call it great. Let me put it this way; my car has slp tri-y headers. The o2 sensor taps in only at the #1 and 5 cylinders. Let's say I had TPI and that a few injectors weren't flowing their advertised numbers. How am I suposed to know? TBI, single plane intake, not a worry (big P&H injectors ).
As for carbs good points, LOTS. More people know how to use them, more people are comfy working on them and they've been around for a while so you don't have to worry about finding parts. Like I've said before, with a carb you've gotta get a pressure regulator or a mechanical fuel pump (and modify tank for just pickup). So there are still costs, it's not just "$250 for a carb I'm all ready to swap". TBI does have one big advantage over a completely mechanical system....timing! $140 and you can recurve your whole timing maps. I don't know about you but isn't that worth it just in itself. Did I mention for that same $140 fuel tuning, tcc controls, LOTS of contants, idle controls, etc. It's not like it's $$$ for tuning tools, if you're reading this post it means you've got a computer, $130 for a burner and $10 for an eraser. You can do even better if you go with a cheaper burner that's just for the 2732 eproms! Figured LESS THAN $100 if just tuning your TBI setup. Too many myths floating around that it costs $$$.
Given the limitations with peoples experience I usually recommend carb to the average joe but if I see somebody that likes computers and isn't perplexed when I show them my setup, I tell them it's worth every cent and then some.
Power for power it's about the same, efi will be more repeatable in daily driven conditions since it's got the self tuning to weather and more fine adjustments (not just choke).
I was just about to go with a carb when I got my winter beater and then I swapped in a walbro fuel pump. All I can say is wow, didn't feel this fast when I ran the 13.8 at 102, wonder what she'll do now that she's got enough fuel!!!
Pablo, read somewhere that you're going with a 350 soon, shoot me a PM. I can't check my e-mail until the 6th.

JPrevost

You don't know the right people .
GM spends 1000s of hours not programming it but testing it in places like Alaska, Mexico, Maine, to Florida. The code is thought out but I doubt it takes them long to get the car running really well. Remember that they needed to make the ecm compatible with millions of vehicles. Some might have had a different batch of injectors or the overlooked fuel pressure. Given only 1 car, your car, you/they/GM/me/average joe could program a good eprom in a couple hours. A great eprom given half a day with a wideband o2 and the 1/4 mile (or other reliable performance meter). If you know how to add and subtract, and you know basics like bigger heads and bigger cam/intake require more timing to come in faster then it's not difficult. If that's new news to you then get a friend and have him help you with a carb swap . That's the easy way out.

Pablo

iTrader: (1)

Actually NJSPEEDER, you can run electronic timing with a carb. Im living proof, because that is how my car is set up now. THe only thing ive disabled is WOT spark advance which i take out of the chip anyways i run all of my advance in the main table. The reason for that is that i dont have the tps attached to the carb.

Dont get me wrong, I love FI. The precision is second to none. With a CAPABLE tuner you can really reap the benefits. But for people that arent natural tinkerers (I am not one of those people, i like tinkering) it just poses more complexity for no reason except that it provides them with far more opportunities to screw up. Someone on the board said it, a carb doesnt care about anything really. THe amount of air passing through it has a direct relationship with the amount of fuel introduced.

The ecm can be hacked etc etc. There are books out on computer programming, alot of computer users.. how many of those want to learn computer programming? most of them just want to get on the computer and go. Granted the computer programmer can make the most of his computer experience.

Im speaking from experience here
Ive run all kinds of stuff on my engine.

One thing TBIers need to do if they really want a fast tbi is get a carb
definately
Teaches you alot about what your combo is capable of since its so easy to get a carb pretty damn dialed in for what its designed to do.
I see too many of you on the TBI board just accepting that your car runs an X 1/4 mile time just thinking its the combo. Tuning plays such a huge part i cant emphasize it enough. Try a carb setup, and use that as your standard by which your TBI's performance should be judged. You oughta be able to match it and gain some low end and alot more mileage, etc... stuff that fuel injection is known for.
IF you arent youll know right off the bat.

It taught me that if you arent using the right tools to tune you are just wasting your time. Id consider some sort of performance measuring device like a G tech and a wide band oxygen sensor as ESSENTIAL. Youll just waste alot of gas otherwise like I did if you dont use one and you are trying to get those low et's.

Pablo

AJ_92RS

First off..... you need to read the original post first. The guy was asking about a 350... not a 305.

And my point of saying "What's a 750cfm @ 1.5"/Hg carb cost? ~$250 w/elec. choke " was UP TO 750 cfm. The Holley TB that you have CAN NOT MATCH THAT... therefore it's becoming a restriction after ~300HP. Why... because as I've said, that's equivilant to ~485 cfm on a carb.

I'm not saying TBI isn't good. it is if you're a computer wiz, have nothing but time, and are gonna drive it in weather ranging from 0* to 100*.

One thing you're forgetting though is..... a factory TBI, or even the Holley isn't much money itself, but to match the flow numbers of a 750 cfm 4 barrel carb, you gotta spend the money on a Commander 950 setup which costs about $1400...... so which is cheaper for HP/$$???

NJ SPEEDER

so you are saying the solution is to burn chips and tune a carb at teh same time? i know very well how you can run teh electronic distributor with a carb, but what is teh point? if you are taking away an electronic control(switching the tbi for a carb) in teh name of simplifying and you leave yourself with a stock timing table you have made no progress at all. if you are gonna burn a chip for one you may as well be burning a chip that does both.
no flame or anythign intended pablo, i just don't see teh logic in it.

later
tim

NJ SPEEDER

i thnk you are missing soem key information here. it does not take 750 cfm to get 400hp otu of a 350. at 6500rpm with 100% VE(which very few street motors will ever be anywhere near) a 355CID motor only requires 668 cfm. you can easily make 400 hp at or a little under 6000rpm(at this point 100% VE is only 618cfm), much less spinning the thing to 6500. so you can see that air capacity is a non issue given a 670cfm holley tb. fuel capacity is also a non issue since there a re a lot of different injector available. a pair of 90lbs/hr in jectors with teh pressure raised a little and a proper chip can easily support 400hp, so fuel is also a non issue.
teh real price differences are these: 1. a good holley carb 650 or 700 double pumper can be picked up for about $300-330 new + teh electric choke conversion that mos tpeople find nice that is another $40, tht comes to $340, which is abotu teh same price as a 670 CFM TB w/454 injectors. 2. to run TBI on your otherwise normally built motor you will need an adaptor plate, a few companies make them adn they cost form about $15-30 usually. 3. everything you need to data log/burn/erase chips on your own is about $150 if you already have access to a laptop(and trust me, one of yoru friends will think this is a cool idea and let you use their laptop), if you decide to go all out and get all teh top shelf chip stuff you will still spend under $300 on it.

the end result is that keeping tbi will cost you maybe $200-$300 more than switching to a carb. that is the initial cost, no go back and see how much money in gas you save and how much more time you spend racing/driving instead of tuning constantly and you can see that the end cost is really equal or slanted towards the TBI.

the system you already have in place is gonna eb teh easier/cheaper long term solution 9 times out of 10.

later
tim

Belstain

Thanks everybody for the great replies.

You guys have convinced me to stick with TBI for now.

My original post was a bit misleading. When I asked what was cheapest I was trying to stay away from the "buy this super way cool gizmo for only $1500 and you'll be set"
An extra couple hundred bucks is no big deal to get the better setup.

The plan right now is to buy all the prom burning tools first and mess around with stock everything else then start upgrading the air/fuel delivery system while I build the 350 out of the car. then when all is ready drop 'er in and see what happens. I'll probably end up building my own throttle boddies eventually because there doesn't seems to be anything big enough at a reasonable price, and because I can (:

MY-92-RS

iTrader: (3)

TBI rules I built my set up in the mid nineties before aftermarket parts where available I am running 454 TBI on a custom gm intake , gm truck 7747 ecm , on top of my 69 302 motor , runs great very fast passes the sniffer, 30 mpg on the high way when I keep my foot out of it

iroczrockz

Hey, I am in the process of trying to build up my car with TBI and a 350. Sounds like we are close to being in the same boat. I need to get a custom eprom myself now and the car should run a lot better, but I have used the stock computer with an aftermarket chip for a 305. I bought a TBI unit from Turbo City with #61 injectors and it runs lean when I am at 65-75mph or so. When in WOT it runs fine (a little rich).

Hollar at me if you want more info on this setup, I am still ironing out the wrinkles.

Pablo

iTrader: (1)

In reply to NJSPEEDER
Im not sure what you are asking, you dont make much sense. Your typing skills are terrible. I'm forced to skip through half of your posts. I think as moderator you should hold yourself to a higher standard and ensure your posts are atleast somewhat intelligible.
That said, I'll make an attempt to address what I think you are trying to ask or comment on.

My choice in running the electronically controlled distributor with a carb is not some part of a master plan of mine as you seem to be implying. For myself it was simply the easiest option. I did not have to buy a distributor, and the advance curve I had allready programmed in the chip (which ran the tbi on my combo) was pretty good. Nor did I have to install anything. It eliminated timing control as a variable in my comparison between carburetion and fuel injection. It simply made the most sense

That said, the idea is not without merit all on its own. It is very easy to duplicate a simple vacuum advance+mechanical advance curve using the main spark table format in the chip. If mechanical-like control is all you desire then you simply have to copy that information into your main spark table. Alltogether, you would come out about even with buying a mechanical distributor and related hardware price wise with buying a chip burner soley to do chips for the spark side of your engine. Roughly 150 for either however you do have alot more labor with the mechanical route since you have to install the thing and rewire the plugs into your hei module and such. That is just the practical side.
Computer spark control is a huge improvement on ANY engine, be it carbed or fuel injection or whatever. Look at all the street car racing classes. There are plenty of cars with performance levels that need not be questioned. Youll also find that most if not all of them no longer mess with springs and weights. Thats a very specialized situation too, probably one that reaps the smallest benefit from computer controlled spark timing. On the street the advantages are immense.

Its too bad really that people here end up taking sides on issues of something as silly as automotive induction like people take sides on issues of religion and politics. They get all huffy puffy for no reason other than that they dont know all the facts and are afraid they are going to get "outed".
It just stifles progress.

NJ SPEEDER

pablo, you just restated teh exact point that doesn't make any sense. you are talking about burning a chip just for a timing table. why woudl you spend time to develop a timing curve on a chip and not a fuel table to match it? seems liek an amazing waste of time to do 99% of teh work for 75% of the result.
i don't know where you got the master plan thing from. i simply don't understand how it saves any time/effort to run a carb and a chip at the same time.
as for any fears you have of getting outed, i don't understand where that comes from either. people have brought good ideas and legitimate positions to this thread on both sides of the matter. if that makes you nervous for any reason taht is more on you than anyone else.
and lastly, if my typing worries you that much you need to find some more to do with your time, cause you woudl have to be bored otu of your mind to take the time to worry about it.

later
tim

NJ SPEEDER

gm spends a lto fo time making sure that every person who jsut puts in minimum grade gas and never changes teh oil has a car taht will last a while. that is about it. gm always leaves a lot in teh bag on every car they build. there was jsut an article in national dragster a few months ago about using pcm editing software on a stock LS1 powered T/A. they found liek 50hp at teh wheels within a few hours. i have personally seen LT1 Edit used to find 2 more mph of trap speed with in 4 or 5 runs at teh track. with teh engine managment watching all teh sensors adn telling you what to change it is really not that complicated.
also, i recently learned from jon prevost that there is software available that will basically build your chip for you. all you do is data log some stuff, cut and past teh information into another program, hit a button and it recalculates teh data for a new chip.

later
tim

raggedout91RS

Hey NJ Speeder, Wher can I get that software that you were talking about?

NJ SPEEDER

check around on teh DIY PROM board and do soem searches for win aldl on this board. all teh software you ned to burn chips for tbi is free and can be found on links on these two boards.


later
tim

AJ_92RS

..............

camaroracer1992

well kids i am living proof of this argument. i had a 305 TBI and went to carb on my 355, granted carb is a cool thing to have under the hood and all and brag about but overall i think it sucks. i wish i wouldve stayed with my TBI and had a chip made for it. i mean i know some people on here that run like 800 cfm carbs and a Victor Jr intake on a stock 305 TBI . i mean the people that are arguing on here probably dont even have matched parts on there car liek a motor that chokes after 5000 rpms and an intake that wants to go to 8500. so over all KEEP TBI its where its at. if it wasnt so great why would GM and all cars today have electronic fuel injection on them and not carbs? you people need to think before you type cause idiocity jsut isnt cool. dont get me wrong i love my Holley alot for what i do with the car but i had tons of troubles in the beginning but NJSPEEDER showed up one night and in liek 30 min and some playing around with timing and the car its got so much power the car wont even hook up and spins through 2nd gear !!!!!! i like my carb but TBI would still be tghe better choice. Kudo's to my boy TIM you rock man cya at Hooters thurs!!!!!!
later
Joe

iroczrockz

AMEN BROTHER to TBI. HOOORAA!!

sbcfreak

Show me how easily you can get a TBI to support 1000+ hp vs. a Carb(s), then I will say TBI rules. Bottom line - the fastest guys on the planet run carbs & always will because it's simply the most cost effective.

IMO - TBI is great for factory, reliable cars. You want to go fast - dump the electronics, ecm, injectors, etc and throw the right carb, intake & heads on a 350 and rage. Open a summit catalog, pick out $2K in parts, and you just made a 400hp small block in a weekend vs. tuning a TBI for months. No fancy chips, tuning, fuel curves, constants, etc. But watch your gas guage go down a lot faster than TBI. MPG and emissions are why we use TBI nowadays. If it was only for power (which we ALL wan't, right? Thats why we're here isn't it?) - we'd still be using big motors, big heads, big cams, and big carbs.

guess thats no surprise considering my name.. But overall - there's no difference between TBI, TPI and Carb as long as the CFM's you need to flow CAN flow. Problem is - getting a TBI to flow 2,000 CFM without sticking out higher than a house out of your hood. Put a single plane and a carb on a 5.7 TBI and it's gonna run like ****. TBI's are for low-end torque (remember the ratings for 350 3rd gens??), but a race motor is made for high rpm's and poorer driveability etc., etc. A single plane on any stock 305 or 350 TBI setup is a very bad choice.

NJ SPEEDER

pro stock cars develop somewhere around 1200hp from 500 inches and a pair of dominators(coming this seson they will be allowed to run the new king demon carbs), cause they are only allowed to run carbs in teh rules. if you look at pro street racign you will see carbs(usually split dominator set ups, read as lots of $$$$$) going head to head with port efi systems every week and you get to see some great racing.

currently tbi can't support that power because teh appropriate injectors and tb's are nto commercially available. the easiest way i can think to do it woudl be to take a pair of dominators and convert them to tbi's sort fo liek the accell set up with large volume bosch style injectors mounts where teh bowls woudl normally be. with a set up liek that you coudl certainly make a run at 1000 hp. it woudl be very costly to build since you woudl be doing all teh development at the same time.

later
tim

brodyscamaro

thats awesome, software like that is really good for yall EFI guys

Belstain

Any of you guys ever seen a 1000hp import? They are all fuel injected. I think the reason we don't see mega powered tbi cars is not because it can't be done but because there aren't any readily available. Everybody knows that you can bolt on a huge carb from a number of manufacturers and it will work. I only know of one that makes decent sized tbi system and it is way overpriced and not even that big. It has become too easy to just open a calalog, order all the parts that are already matched, and slap it all together. Nobody wants to do any real work anymore. I like to make my own go faster parts because I am a tweaker (a really cheap tweaker) and if I actually make it myself then it is different and really something to be proud of, not just a "I wrote a check and this is what came out" kind of car.
To qoute an article in this month's CARCRAFT "Thats why we call it CAR CRAFTING not CAR MAIL-ORDERING"

AJ_92RS

I said this once, but my post is gone now.

TBI can support a butt load of HP, but it cannot, and will not be done as cheap as a carb. The reason is the 2 barrel TBs can't flow enough, and the injectors can't flow enough.

You can buy a unit called Commander 950 that is a 4 bbl TBI system with 4 injectors. It comes as large as 900 CFM which will produce A LOT of HP with the proper injectors, BUT IT COSTS $1400!!!!!!!

It comes with the ECM and all the sensors, etc. It's certainly cheaper than switching to a new TPI unit (like a Stealthram), but it's not as cheap as a carb.

Here's the question that the 'thread starter' asked....

Carb. Although the REAL answer is "Nitrous"

Then he asked...

Carb.

He didn't ask "How much HP can TBI support?" Nor did he ask "Which is cheaper?" He asked those questions in one combined question.

He want's to know "the easiest/cheapest to get that power level?" IE.... HP/$$$ ratio.

That's his question. The answer is carb.

A stock TB, nor the Holley 670 replacement TB WILL NOT easily support that much HP ("easily" being the key word since that is part of his question).

Now....... since this has become an OPINION contest I'll post mine. I would rather have TBI. I am building my motor around that, but later on (after I win the Lotto ) I would love to change to the Commander 950. Then I'll get all the power of a 4 barrel carb, AND the precise control of EFI. What more could I want???

Dominic Sorresso

I am with JPrevost and NJ Speeder. I've got 350 Xfire putting out close to 350hp at the crank and 435lbft of torque(the stuff that you drive). The TB's can be sleeved to flow 750cfm using a 2.13" throttle plate and you can use the 454 injectors for the fuel. 2 90# injectors can support 360hp using a BSFC coefficient of .5. You can tune it so it gets it a bit better. I am using the 80#. Haven't put it the WB O2 on it to see what's happening at WOT.
I played with carbs a lot in the 60's and 70's. I love the ability to tune and create different personalities for the motor based on the requirement like cruise vs. WOT. Carb is like J.C. Whitney.
"One size fits all."

iroczrockz

Where do you guys get #80 and #90 injectors? Can the computer handle that for a daily driver?

Dominic Sorresso

IROC,

I have a set of 90# injectors in the garage or www.gmpartsdirect.com and
YES the ECM will handle it.
BUT you need to tune.

iroczrockz

Would you recommend them? Why aren't you using them? Are those too much? Do they give you any unwanted side effects? Last question: Would you be willing to sell them?

ThirdGenFire

I know it is not a TBI I am going to talk about but as fuel injection gets more and more fine tuned it gets faster and faster. Soon it will be up there with carbs. Take the S.A.M.(School of Auto Machanics) 1999 Camaro SS(LS1) it has been modded and has run 9.80's now with no power adders at all. Thats proof that EFI is about there now. TBI is a good thing. I had a 305 TBI then went 350 TBI and now 350 with a carb(just got a 90 bird with a 305 TBI!!!!). I know the power is there, you just gotta know what you are doing. Chips, tuning etc.. is all part of the game. If carbs is what you like then you are gonna think it is easier to tune them, same thing with EFI. Fast is fast. Carb is tops still but EFI is coming and you know it will dominate soon. Just ask Mike Morgan or Mike Meany. EFI is here to stay and it keeps getting better and better. TBI included.
Laters

NJ SPEEDER

any "side effects" that a different injector may have will eb teh result of tunign mroe than anything. you really need to get into the car at teh chip level to make corrections or you won't see max potential from any part.

later
tim

Dominic Sorresso

I would recommend them IF you need them. I knew I needed larger than stock injectors(66#) when I dyno tuned the motor. It started to go lean at WOT around 4000rpm. AFR was near 14:1 by the time I got to 5000rpm. And the power curve tailed off in conjunction with that. I haven't had a chance to dyno tune the motor since I went to 80# injectors and 1.6 ratio rockers. In order to use the larger injectors you'll need to tune the chip setting the correct BPW in the Constant Table and then tune the Main Fuel Tables.
Wasn't sure I needed the 90#. I am pretty sure my motor could easily use them now, however. I wanted to start smaller and see what happened.
Finally, Yes I'll sell them. They are brand new.

iroczrockz

Couldn't find those injectors on the gm website. Don't know the part number either though.

Dominic Sorresso

They're 190 bucks including shipping for the pair. At least that's what I paid for them.

Here's the numbers for the two injectors:
Application | ml/cyc | BWNew | BWReman | GM OE Number(s) | Standard

454 2bbl Truck (89) | 124 | 57021 | 27625 | 17111784, 17111865 | TJ11 Red/Dark Red 80#
454 2bbl Truck (92) | 129 | 57229 | (none) | 17091045, 17091046, 17112557, 17112567 | TJ27 Blue/Black 90#

Cheers!

AJ_92RS

See..... right there you are NOT answering the original question.

You can stick with NJSpeeder and JPrevost all you want with TBI, because it can make descent HP. That's a gimme.

The quote above just proves that HP/$$ ratio... carb wins. You're talking like it can be done for the same cost, but it can't.

Read my last post again and answer the question, and try not to "defend" TBI when nobody's knockin' it.

Dominic Sorresso

You read the post. I was making 320+ HP using the stock injectors. That's why I said IF. And whatever you save buying a carb goes right down the venturis for gas mileage. They aren't anywhere near as much fun tuning either. But, hey, this is a free country. Knock yourself out.

iroczrockz

Well If you plan to use them that is ok. I was just wondering. I think I might need them but I haven't done any tuning yet. I have 61# injectors now and they are "matched". With the thermomaster chip I have for a 305 in a 350, the motor runs lean at cruising speeds all the time. At WOT it is ok it runs at the normal mark (air/fuel gauge). BUT, If I can, I would like to skip the expensive middle stages of tuning a chip then getting bigger injectors and doing it again. Know what I mean? What size motor did you use them in?

Pablo

iTrader: (1)

Hey NJSPEEDER.. just out of curiosity, how many chips have you ever programmed?

NJ SPEEDER

i don't do chips. i live near jprevost, he shows me all teh neat new toys and how they work when he is home from school. i am getting an old laptop, so i will prolly be burning chips by spring.

later
tim

Dominic Sorresso

IROC,

If you are saying that at WOT the normal mark is 14.7:1, that's too lean. You should be down in the 12's. Good way to grenade a motor. Both the 80# and 90# injectors were for my 350 Xfire. If you are interested in the injectors, send me an email.

iroczrockz

I don't understand what you mean by 14.7:1. I haven't got a lap top and I have never burned any chips. I am really a greenhorn when it comes to the computer. I understand it won't be that expensive to get into programming my own chips but that is really my weakpoint.

The only way I have to tell it is running rich or lean is my air/fuel gauge. I was thinking it would be wiser to get bigger injectors and then get a custom eprom, instead of getting an eprom and then injectors and getting another eprom. What do you think?