ok, maybe not easy, but definitely doable, and for not a lot of money.

I've just finished going all the way back to the beginning and reading the tbi posts.

it looks like the answer to the 305 was here some time ago and got lost.

as i went through the posts, i came across a number of references to a great article in the october and november 1989 issues of hot rod magazine where they took an '89 rs 305 tbi 5 speed, didn't touch the short block, changed cam, heads, intake, headers exhaust, gears, etc., and went 14.30s on street tires. they added 97 hp and almost 100 lbs. ft. of torque with careful parts selection and tuning. there was too much low end torque and they spun the tires badly. additional tuning would certainly have put them in the high 13s.

one thing that becomes clear when reading the articles is how critical parts selection is.

i found the pdf files for the articles on a member's homepage. here are the addresses. copy and paste them into a new browser. i don't know why, but they won't work if you just click on them.

http://members.tripod.com/GRK_Taz/tech/camaro.pdf

http://members.tripod.com/GRK_Taz/tech/camaro2.pdf

the keys to the car were the cam, the adapter for the tbi unit to the intake and the chip. unfortunately, the company that did the work (traco engineering), no longer exists. i've tracked down one of the people involved, but haven't gotten a reply to my emails yet.

the articles didn't give the specs on the cam, which they said were critical. at the time, traco was marketing the cam and didn't want to give the secret away. same with the adapter. they tried the performer tbi and the holley adapter to use tbi with a regular performer intake and found them wanting, so they made their own adapter and offered it for sale.

the only mod they made to the actual tbi unit was to switch to 350 injectors. it's obvious from looking at their success that all the debate over 454 units or holley 670s is superfluos ... you can do it with minimal modification to the stock tbi.

looking at the hp and torque graphs, i think they would have been better off with a single plane intake rather than a dual plane to cut some off-idle torque so it could launch. they may have had too much gear, too. i think the car would have launched better with 3.42s rather than 3.73s.

the heads they used were ported vette aluminum ones. i don't think world products torker sr 305s were available at the time. i'd either use those or shaved vortecs. i like the vortecs better because they'll swap to a 400 later, although i'll have to use a thick-azz head gasket to make up for having to shave them to work on the 305.

i think finding the specs to that cam, where to get that tbi intake adapter (or at least a template of it) and finding out what they did with the chip are critical to making this work. there are plenty of posts on here from people doing similar mods and not going nearly as fast. it's obvious that the 305/tbi combination is extremely sensitive, with a very small "sweet spot" to make serious power.

now, i've seen the posts from the guys about the "13 second challenge" and i'm sure they'll cry "foul" over the head swap, but i think it's crazy to spend a bunch of money porting and polishing 305 heads when you can buy better flowing aftermarket heads off the shelf for nearly the same money or less. my old grand dad used to say: "you can chrome plate a turd, but all you'll have is a shiny turd". i think 305 heads suck. any money put into them is money just thrown away.

i'd like to get some help running down more information on the combo in that article. make it a tbi board project or something. it's depressing to see people doing so much to their cars to run 15s and high 14s when that article shows the expensive mistakes they're making. i'd like to use that article as the basis for a series of tech articles to point tbi newbies to so they can save themselves grief and wasted money.

thoughts anyone?

 

once ti gets warm and tracks start openign you are gonna start seeing a few 13second 305's on teh board. there are a bunch fo people working on it and a fw even doing it with teh stock heads.
that article was teh best proof ever that most of teh major magazines don't know jack about any type of fuel injection or how to take advantage of anything but a 350. they had way too much cam, no chip, and the wrong injectors. pretty much a worthless article.

later
tim

 

hey look at that

 

well, that's the fastest stock shortblock/stock tbi unit i've seen yet. if you'd read the articles, you'd know they did have a custom chip. you'd also know that traco engineering, the company that did the work, was one of the first companies to delve deeply into getting more power out of modern efi. while they specialized in tpi (and made huge power with it), they appear to have done a pretty good job with the tbi, too.

sneer all you like, but 300 hp and over 300 lbs. ft. torque from a dish-piston, stock shortblock 305 looks pretty good to me. no chopping up the tbi unit. no bigger fuel pump or adjustable fuel pressure regulator, just simple, basic, well thought out bolt on mods to go faster than any similarly equipped 305 i've seen. what are you getting out of yours, and with what mods? consider how much more might be in that combination with better airflow from the tbi, fuel pressure adjustments and better cam timing.

i got an email from a guy this morning who said they were right about the intake manifolds. he put a performer tbi and a regular performer with an adapter on it on a flow bench and got significantly better results from the adapted performer.

and too much cam? any cam that makes that kind of power, idles smoothly and runs well during daily driving can't be too much cam. again, what kind of power are you making? and with what?

dude, why are you always on the attack? in going through all the posts on the tbi forum, i've learned more about tbi in a short time than i would have thought possible, but i've also seen you, again and again, ridicule anyone who dared to disagree with you. this is a discussion board ... discussion. look into it.

 

Do you honestly think you can justify coming on here and telling a moderator that has been here as long as Nj speeder that he doesn't know what he's talking about when you've registered on this site a month ago? This article was talked about a while back I recall a thread on it. NJ was right about what he said don't be so quick to come on here and start telling people with far more experience and knowledge of TBI's that they are wrong and you're right because you've learned oh so much in your month of experience. He is not "always on the attack" either, he happens to be one of the first ones on the board that will answer guys questions and help them out, and I'd like for guys like that to keep posting their answers and not stray away from posting on the board or something because of unjustified attacks by rookie members.

 

let me go through this piece by piece for you.

i went quicker on a stock short block than they did, and mine still had a stock cam in it and stock chip in teh ecm.

300 hp from a 305 is nto an amazing accomplishment. stocker guys have been doing it since the dark smog days of teh mids 70's, sorry if i am not impressed after 20 years of development.

on a flow bench you will see a gain in flow from an adapted manifold most likely because all teh adaptors out there have 2inch bores, the performer tbi has a stock 1 11/16th bore. that is a lto of difference in area to let air in.

if you look around on almost any small block related board you will see that since the late 80's technology on dual pattern cams has come a long way. most people today are running with teh same hp adn much smaller cams in teh car because modern ramp technology allows the cam to create cyl pressure instead of leaving it all up to the piston.

i tell people things the way i see it. if i come off a bit too harsh for you soemtimes i am sorry. but this is the way i talk to everyone who knows me and this is the way i have talked on this board for a very long time.

later
tim

 

1. while i have only been on this board for a month, i have been building daily driven, fast street cars for more than 20 years. i'll never try to pass myself off as an expert mechanic or engineer, but i'm certainly not a 15 year old who doesn't know know a fuel injector from a fuel pump, either.

2. when i bought my current car, i wanted to do something different, so i specifically looked for a tbi. the difference between me 20 years ago and me today is that i do a lot of research before i start making any changes. that research led me to this board. early on, i started a thread asking for advice on making the tbi work, how much horsepower and cubic inches tbi can support and whether it would be cheaper/smarter to swap to tpi or a carb. there were some pretty good posts in response to that, but, as soon as someone said they thought the tbi was junk and i should switch to a carb, nj speeder shut the thread down, saying "there's no place on this board for that kind of discussion". whoah .... read the tpi board or the carb board. they have those kinds of discussions all the time. no one was being flamed, no one was using bad language; he shut it down simply because he didn't like the opinions expressed. i emailed him and told him i'd been getting good information from those posts and didn't understand why he'd shut it down. he never responded.

3. over the next couple of days, i noticed newbies such as myself coming on and asking the same questions over and over. figuring that was frustrating to people who'd been here for awhile, i decided to go back to the very beginning and learn more about tbi before i asked more dumb questions or voiced uninformed opinions. while doing that, i noticed nj speeder time and again shutting down threads simply because people dared post opinions he didn't agree with or hammering anyone who said something he didn't like.

4. look at his response to my post:

"that article was teh best proof ever that most of teh major magazines don't know jack about any type of fuel injection or how to take advantage of anything but a 350."

first, the people from the magazine didn't do the work. they took the car to traco engineering, a company with a long history of building powerful racing engines. they were a dominant force in can-am racing for years, for example. they were also one of the first major engineering firms to work at making serious power with gm electronic fuel injection. before arizona speed & marine or t.p.i. specialties did it, traco was building 450+ hp tpi engines and selling them. 300+ hp and 300+ lbs. ft. of torque from a stock short block tbi 305 sure seems to indicate not only interest, but success at taking advantage of something besides a 350.

"they had way too much cam, no chip, and the wrong injectors."

while they wouldn't give the full specs on the cam, the article described it as having "4.80-inch lift like the new chevy 350 h-o's hydraulic roller, but with less duration and a different lobe separation to be compatible with the 305 tbi setup" how could anyone know from that whether they had too much cam or not? half the people on this board are running more lift than that. also, they did have a chip. they even cautioned that their chip was programmed specifically for this application and would probably not work with different components. the injectors they used were 350 tbi injectors. you regularly see people on here suggesting that very swap. more importantly, if they have the engine on a dyno and the 350 injectors make more power than the 305's injectors, how can they be wrong?


"pretty much a worthless article."

first, he was completely wrong on the cam, chip and injectors. second, how can an article that shows an intelligent use of simple mods that anyone could duplicate in their back yard that puts an '89 f body in the low 14s be worthless? does he have a better way? a proven better way? if so, give it, don't just arbitrarily dismiss something that obviously works.

these were experienced engineers with a long track-record of success at building powerful engines who took the 305, put it on a dyno, put numerous combinations to the test and published the results. then they put it back in the car, took it to the track, and laid down times that i'd venture to say very few, if any people on this board with comparable setups could duplicate.

how many people have gone out and bought tbi performer intakes who might not have if they'd known professionals had tested it against a standard performer with an adapter on a dyno and found it wanting? i wouldn't.

the bottom line is that this is a discussion board. there are often many ways to reach an end; often there is no one "right" way. that's the fun of the discussion and debate.

i thought a moderator's primary duty was to make sure people followed the terms of service of the board. i never knew disagreeing with the moderator or offering a different point of view violated those terms of service.

i've owned 3 small block street cars that i drove daily and could drive to the drag strip in the same street trim i drove every day, pull up to the line, uncork 12 second runs (on horsepower) and drive home. on one of them, i could hit the nitrous and run 11.70s ... then drive it home. i may be new to tbi, but at least i took the trouble to read the posts from the beginning before i began offering my opinions. regardless of what i have to offer, however, my understanding is that i'm able to express my opinion here as long as i don't violate the terms of service, regardless of how intelligent or stupid they may be. is disagreeing with nj speeder is a tos violation? someone please correct me if it is.

 

disagreeign with me is not only allowed btu encouraged. sinc eyou are new here you will nto know what i do when i have to shut threads down. after i close thread i go back and take otu all the arguments adn flaming that goes on in them. that is the only way that i close a thread. when i have a problem with the way a thread is going i will contact teh parties that are at teh root of my concern and let them know and ask them to help correct teh siutuation. teh job of a moderator is nto to sit by and hope no fights break out, it is to help keep topics on point and moving as well.
i only have about half the time into racing adn working on cars as you, but i have had enough tiem to work on several streetable 10, 11, and 12 second cars. some with power adders and soem with out, some fuel injected and soem carb.
to only get to 300hp on all those parts to me is terrible. soemthign was seriously lackin in the combo, and that article has been poured over on this board enough tiems for me to be very confident in my position.
you don't need 350 injectors to run low 14's. you don't need .480 lift to run low 14's. you don't need a custom chip to run low 14's. if i had access to all the dyno time and chip burning that they did i can imagine my car woudl have been a long way into teh 13's, but since i am on a much lower budget, i had to settle for 14.2's on a stock cam, chip, adn injectors(i had a AFPR).

later
tim

 

tim,

i was writing my last post when you posted this one. i didn't see it till after i posted.

i respect your opinion. while we may still disagree, you're at least giving reasons rather than just being outright dismissive. that gives me the opportunity to consider your reasons and maybe learn something from them.

"i went quicker on a stock short block than they did, and mine still had a stock cam in it and stock chip in teh ecm."

you went faster than 14.20s on a stock short block with a stock cam and chip? i'd love to know how you did that. i see so many people on here swapping induction, intakes, exhaust, gears, etc. and still running 16s and 15s. that and the reading i've done elsewhere have lead me to believe the heads and cam on the 305 are virtually worthless.

at one point, i'd decided to just dump the 305 and the tbi and swap to a 400 with a tpi. i've since decided i like the tbi and want to stay with it, no matter what engine i eventually end up with. that article also made me curious as to what i could get out of the 305. at some point my 90,000 mile 305 short block will give up the ghost and i'll almost surely swap in something else, but, in the meantime, i want to see what i can get it to do.

"300 hp from a 305 is nto an amazing accomplishment. stocker guys have been doing it since the dark smog days of teh mids 70's, sorry if i am not impressed after 20 years of development."

today, i'd agree with you, but that project was done almost 14 years ago. again, looking at what people on here are trying, that project made more hp than a lot of people here have been able to. i want to find out exactly what they did and what parts they used, then hopefully apply 14 years of technological improvement to my setup.

"on a flow bench you will see a gain in flow from an adapted manifold most likely because all teh adaptors out there have 2inch bores, the performer tbi has a stock 1 11/16th bore. that is a lto of difference in area to let air in."

the bottom line still is that the adapted manifold flows better. beyond that, the adapter they made flowed better than those commercially available. in the picture of the adapter in the article, they had the holes covered. i'm guessing there was something about the shape of the openings that made it work better. maybe it's where the tbi unit is mounted on the plate (further forward or further back than the holley?). regardless of what the difference(s) are, it seems worth the effort to find out.

"if you look around on almost any small block related board you will see that since the late 80's technology on dual pattern cams has come a long way. most people today are running with teh same hp adn much smaller cams in teh car because modern ramp technology allows the cam to create cyl pressure instead of leaving it all up to the piston."

i agree. my point is that they made more power than most thought possible at the time with that cam. i want to know how it was different from what other cams were available at the time, then hope those differences apply to today's technology.

i think virtually everyone on here would admit that the 305 tbi setup has been largely ignored by the performance industry. when something appears to work, it makes sense to dig up as much as possible on it.

i'm applying the "measure twice, cut once" theory to my car. before i change anything, i want to learn as much as possible. i've dug up article after article in magazine archives where they made similar mods to 305 tbis, ran 15s and declared success. this is the first i've seen with basic, non-exotic mods that gave that sort of result. i want to find out why.

 

my combo was:
*edelbrock performer centerbolt heads, 2.02/1.60 valves, 60cc chamber, and i think they are liek a 175 port(that is from memory, i may be wrong) they were out fo the box and onto the car
*comp cams 1.6 roller tipped rockers, these were very nce and seemed to maek teh power carry a lto further through the rpm band.
*performer tbi intake, out of teh box and onto the engine, never touched.
*edelbrock "iroc" headers, 1 5/8 primary, 3inch collector, 3inch y-pipe, cat eliminator pipe, borla adjsut able cat back(what an overpriced POS the borla was)
*dana44 rear(firehawk rear) wiht posi and 3.54 gears. this is a spot that i feel i gave a lot up. teh gears were good enough for a gain, but a bit more gear woudl ahve been way better. if i had it to do again i woudl prolly chose 4.10's
*transgo shift kit, 2000stall convertor. teh convertor was another weak spot. 2000 is nto enough to get a good gain. for a stock/mild motor a 2600 stall woudl be a much better improvement
*ultimate tbi mods adn diy afpr(later i got a JET afpr in trade for soem work i did, it was much easier to use) i woudl have liked to go back and do that tb over again. it was teh first one i ever did and later on i made much nicer ones after i had doen 3 or 4 of them.

the suspension was mostly oriented towards drag racing, big brakes, giant sway bars, eibach pro kit springs, and bilstein shocks are not teh best thing for drag racing, but i had hoosier quick time pros to make up for that.

the car woudl cut very low 1.9 60ft's all day long adn run in teh 96 mph area consistantly. i knwo that with any number of minor adjsut ments ti woudl have been well into teh 13's, teh chip woudl have been a huge gain all by itself.
much like i am sure you can do since you have been in teh game so long, i tuned the car by sound, sight, adn smell. i messed with teh fuel pressure and timing until i got the best times out fo it and then just left it there. the car idled liek crap cause it was too rich and by teh end fo teh 1/4 it woudl be leaning out because the injector rate was too soft. i coudl also feel teh car lay down because the timing table was too weak since the addition of the 1.6 rockers gave it more duration at .050.

if i had it all to do over again, i woudl avoid getting caght up in the hype that the stock heads are a waste of time. they are far from teh worst ever and are very capable of feeding a 305 enough air to get above 97mph(the traditional breaking point for getting into teh 13's). teh stock cam is a complete joke though. replacing it with a stock L98 or LT1 cam has been shown a bunch of times to be worth a ton of power. i think soemoen got liek 4 or 5 mph of trap speed from an LT1 cam wiht out any other changes.

later
tim

 

"the car idled liek crap cause it was too rich and by teh end fo teh 1/4 it woudl be leaning out because the injector rate was too soft."

would a vacuum adjustable fuel pressure regulator have helped with that?

 

Hey Njspeeder i dont know if you remember Im the kid that had the 89 formula tbi 350. I finished 4th last year bracket racing at the nats. I got a question though when you were running low 14's did you still have your ps pump and your heat and all that good stuff cause i remember you telling me that you took all that stuff out. Not trying to proove you wrong or right just askin

PS NJSpeeder knows his stuff i talked to him a couple times in person.

 

I found the article interesting to read and haven't seen it on here since I've been reading the TBI boards a lot (~6 months). I like the fact that a mag. published using the TPI cat and header kits for a TBI application which should be made as a sticky on here along with the fact they were running a stock TBI unit which should also be made a sticky that the 670 unit should NOT be your 1st mod. It also the first baseline test on TBI car I've read which gives people a time to strive for before doing any mods other than general maintence. I think it was around 16 flat @ 85 mph.

I don't understand NJspeeders thoughts about the "unknown" cam being too large, I thought the dyno charts looked great IMO.

When the search works again you will find a bunch of people going for 13's on the stock heads (like me). I know back then they didn't have vortec heads, but I don't think the stock corvette heads are that good choice in stock form considering they made similar power as the iron headed f-body engines. I bet they would've got the same results with TPI heads or LG4 heads (I trapped 96 mph in my 305 TPI w/ its stock cam and heads in a much heavier car), which would've save them a lot of money.

All this got me thinking maybe we should have sticky on here for first mods to be done to a 305 TBI.

Get car in a good like new tune.
Air Intake
Headers and exhaust
Gears and posi
mild Cam and valve springs
suspension

And throw in custom chip tuning, VAFPR, and aftermarket intake manifold in there somewhere too.

After all that then I think different heads(due to cost and labor reasons) and a larger TBI unit and inj. are needed top make more power.