JPL87SS

hi i'm looking to buy a camaro prolly in about a year or two but right now i'm trying to learn everything i can about what to do to it to make it go fast for not very much money so my question is is it possible to make over 300 hp outs of a 305 tbi for under $1500?
any info would be appreciated.thank you

Inwo

Sure, take out the tbi, take out the 305, put in a real engine like a 350 and some decent heads/cam and a carb. No problem.

Mark A Shields

Why get TBI? If you want to keep the orginal motor I would look into TPI, a 350 if you can afford it.

89ProchargedROC

buy a TBI, convert to carb, spray the **** out of it

you'll easily have 300hp

JPL87SS

is anybody gonna take me seriously?i want to leave it tbi but buy a better tbi unit i think there's one from holley that has 42% more flow and i want to have the 305 1 beacause better gas mileage 2 insurance purposes and three because it'd be unique and it has potential i just need to know how i can do it with out spending too much money

jdrobley

don't waste your money on the holley unit... especially if you are looking to make 300 horses. the stock one should do. a better cam and exhaust system should get you there. also check out the free mods and other ideas under the tech articles. if you really want some opinions, go chumming in the tbi board. just take everything with a grain of salt.

jess

TBI305Camaro

with heads/cam/intake/custom chips and a modded TBI you still wouldnt be at 300hp...if you want to make 300 hp youll either have to do all the above (already way over your budget) and spray or it will have to be a 350...

dont get a TBI car unless you come across a really good deal or something. its really not a great system.

Mark A Shields

You'll prolly get more mpg with TPI, and there's not much if any difference between 305-350 mpg.

I don't think insurance will change either, basically you have a V8 either way.

Yeah, cam and exhaust will get you no where near 300HP, and don't TBIs come with sucky swirl port heads.

SSC

"is anybody gonna take me seriously?i want to leave it tbi but buy a better tbi unit i think there's one from holley that has 42% more flow and i want to have the 305 1 beacause better gas mileage 2 insurance purposes and three because it'd be unique and it has potential i just need to know how i can do it with out spending too much money"


The truth is for all the porposes you stated and your goals 300HP from a 305 aren’t realistic, doable but not realistic.
A hundred hp gain with your 305 is gonna take "as mentioned " a high lift cam, real heads "there goes the good gas mileage" a new intake that will support the new needs, and a exhaust system to expel all this new gas. You end up with a 10mpg 300 hp 305, IMO because I have one in my 91 GMC, not worth it!

An engine swap does not increase insurance. Hypothetically speaking "if it did" who's gonna say, "Hi Mr. Insurance man, I just replaced the 200hp lO3 engine in my car with a 300hp 350," any one? No one knows what engine you have unless you come out front and say, "Ive got a 350." Note; claiming a 350-383-400 is a 305 is a good thing.

RJR99SS

well a 300+ hp 305 tbi can be done....but if cost is a problem, dont even think about it.

it'd take a total engine rebuild, and some heavy modification to the original tbi.

everyone is right that if you just put a carbed 350 in you'd get 300+ for under 1500. its not the most elegant option....but it works...

HrdRockA4305

You're insurance won't change. They don't know if you swap engines, and you don't have to tell them. They just go by what your VIN says. You could have an early Iron Duke car with a 454 in it, and pay the insurance rate of the I-4.

Pukka

250 - 275 HP is much more realistic if you still want to keep it as a daily driver. It can and has been achieved. Whats more realistic is that you won't get it done for less than $1500, even if you do the labor yourself. Just my .02

scauffiel

One of the car mags did a 305 build up that got 325HP out of it - for just a bit under $1600 (IIRC). I have the article up on my site HERE.

Steve

JPL87SS

wow thanks for that article but now my only questions are. . . . . . .how much mileage do you think i'll get and how hard is it to convert to carb from tbi? thanks again

Mark A Shields

You'll need a vacuum adv. distributor and take care of the TC LU with carb.

RJR99SS

milage is definatly going to be out the door with that setup, they completly blocked off the egr if you didnt notice. I'd say about 10 mpg is a good estimate...

84TransAm

Just because you've got no EGR (or any emissions devices for that matter) doesn't necessarily mean you'll get bad gas mileage. I'm running NO emissions devices, [nor an EGR unit] and get 23 mpg

JPL87SS

cool thanks :-)

ME Leigh

I also get a bout 20-25 mpg on the highway when i baby it and keep it under 60 mph.

ME Leigh

I also would say just convert the tbi over to a carb, its much eaiser to build power that way. Get rid of all the emission equipment, and get an new intake ( i recommend a weiand stealth) and a pre-cpu distributor. I would also get "hedman hedders" and some good heads.

ME Leigh

Here are some more 305 build-ups http://www.inter-scape.com/ray/305buildup.htm

TBI305Camaro

I plan on getting a brand new lo5 (1500$) putting a larger cam in, adding a edelbrock intake and a holley bet it will be very drivable and probably wont do half bad on gas. plus ill have the insurance of knowing i have a brand new engine so it should last another 14 years if im lucky pretty sure the 108k 700r4 wont tho. getting ready to throw in a tranny cooler. hopefully i can squeeze every last mile out of her before i have to get another.

JPL87SS

what size exaust should i get because i was planning on a 3" but i heard that it would be hard to hide and i would bottom out alot and wouldn't 3 inch be kinda extreme anyway?thanks

scauffiel

Okay then, a couple of things:

You want to (a) go fast, (b) for under $1500 and (c) you want it to sip gas.

Choose two.

Some guys have real good luck with carbs, some don't. I converted from TBI to Carb and went from 18 mpg on a 305 to 11mpg on a 383. I've got luck, but it's all bad as far as mileage is concerned.

Gee, that looks familiar.

I have a single 3" exhaust for my 450HP mill and it cost me around $300 for it to be built for my car and if you noticed in the magazine article that they used dual three inch pipes through Flowmasters you would probably realize that it isn't that extreme and you can't see my exhaust unless you get under the car and who are you hiding it from anyways and I don't bottom out on my exhaust unless I'm driving like an idiot over speedbumps in which case I deserve to have my exhaust smashed and maybe you should consider using punctuation instead of the word 'and'.

I think the "MESSAGE" that should be spread around and I mean REALLY spread around (maybe make it the motto for thirdgen.org, maybe make new members type it out 100 times before being allowed to post - j/k) is:

Speed COSTS. How fast do you want to SPEND?

S.

E-Z Rollin

Anyone thatdoesn't think you can make 300 hp with a 305 sbc and for $1500 needs to re-think it! It's been done with a set of pocket ported H.O. GM 305 heads,9.5:1 compression and a streetable cam.

JPL87SS

Hey,sorry about my punctuation,grammar ,and stuff like that.I know how,but i just kinda forget about most the time on the internet.Anyway how mouch would the whole exaust set up cost? headers, 3" pipe,and cat-back system.

burnoutrpm

the switch from tbi to carb is a breeze!!!!!its just a matter of a lot of time spent dion it. piece of cake

Mark A Shields

Don't listen to the people that said not to get 3". An exhaust shop told me it wasn't worth it. It was very worth it. I don't bottom out ever, unless I have like 3 people in the back seat over a speed bump. There's a sound clip of my exhaust in my signature , the cat-back cost me $200.

Sitting Bull

Yeah, I agree. It will depend to a certain degree what sort of shape the 305 is in but it is not hard with $1500--especially if you shop the ads for good used gear AND can do most of the wrenching yourself.

Slade1

http://www.goingfaster.com/spo/praisetbi.html

This should tell you everything you need to know about TBI.

http://www.goingfaster.com/spo/325_h...chevrolet.html

Here's the build up cost in today's guide
Comp Cams xtreme energy 262 $169.99
World Torquer heads $314.99
Performer EGR $212.99
Hooker headers $349.99

this alone with labor should be $1500 but would gain a lot.

A TBI uses less fuel than a TPI, I'll take that challenge up anyday in terms of efficiency. A TPI pulses ALL injectors to spray at the same time. Now we all now each cylinder needs fuel and air at different times, and although this is a step up from TBI, a TPI wastes more fuel than a TBI, but a TPI has more fuel to work with when power is needed. Do not confuse TPI with GM's wonderchild SFI which is the evolution of TPI where each injector is pulsed when the individual cylinder needs fuel and air. I'm not saying TBI can make more power than a TPI setup, I just state its more efficient with fuel than a TPI. I can get 22-24 mpg out of my TBI and do mid 15's on a pretty much stock setup, the same can't be said for TPI or 350. It's only worse with the higher ci engines, as there is always a trade off. Jump from 305 to 350 and you get more acceleration, less fuel mileage. So you have to choose what you want...

Do you want a daily driver or a drag racer?
Do you want economy or power?
Street/strip or middle of both?

You want more power, get a 350 and do the equivalent mods. You can pull up to 400 HP with that, its not a difficult choice.

You want a street machine that can do the strip and take you to work 5 days a week, do the 305.

You worry about insurance... why get a camaro?

From the sound of it you are concerned about the money, don't let anyone tell you you can't make a decent powerhouse out of a 305, because the truth is you can and there are many 305 owners to prove it. When I think of 350, I think of LS6. She's not even a real 350... 347 ci and pushes out 400ft/lb of torque from the factory. Now that is an engine of beauty. You flow air in/out better AND get better mileage AND get more power. The LS6 doesn't add more ci... she takes some away... she simply does something better than any old 350 could do, and that is flow air in and out better. So with that in mind, a 305 can make decent power. Its all possible. Anyone that says a 305 can't make real power because its displacement is less and ONLY getting more displacement is better, I say LS6 and disprove that.

TBI305Camaro

only reason the ls6 can do it is because of technology. the more technology progresses the more MPG and power we will get...look at 4cyl now. some are pushing 250hp NA. hell thats not bad. an old carbed 350 is not going to be nearly as efficient as the ls6 but if you want to go fast you will spend money on gas and stuff will break...you start pushing 400hp and stuff will break. thats just how it is. thats why im just gonna build me a mild 350 that i can drive everyday. yeah i wont get great milage but thats not what im worried about. The car is paid for so i have plenty of gas money. maybe someday when i can get a second car then the camaro will become a race car but for now id rather look good and run good.

ChrisFormula355

If you wanna go REALLY cheap and fast......get some Lg4 305 heads and port the snot out of them........get a RPM intake and carb, extreme energy 262 cam, and the usual performance components like headers and gears and such......and you'll have a little screamer. But yes the mileage will suck Tim Burgess has a 305 with these sorta mods and ported stock heads with TPI and I think he runs somewhere around 13.3 @101 on the motor. My girlfriends camaro runs 98MPH in the 1/4 with stock swirl port L03 305 heads........and I"m putting some extensively ported Lg4 heads on it in a week or two to see how much HP they are really worth.........All in all though you are better off putting in a good cheap 350 short block with decent heads and make more power for less money.

TBI305Camaro

seems like there are sopme quick LG4s out there but hardly any quick lo3s...i dont think its the heads as much as the induction. If for some reason i decide not to get the 350 a carb will go in the TBIs place along with a cam and world heads

cort351w

Slade, you do know that 305's suck because of how their displacement is made, not because of their displacement, don't you. (This is why the 5.0 is a good motor and the dz302 was a good motor.)

Not to be a dick, but how did we get on the subject of the LS6 (which is a 346, BTW)? The other thing to remember (and not to take anything away from the motor, but...) is that the Z06 (and the few ZL1's) has a six speed tranny. The second overdrive is good for mileage.

Also, a properly tuned tpi can get LS1-league mileage. You may want to check out the diy prom board and do a search for Glenn91L98GTA, TRAXION, or Grumpy. Glen is getting 30mpg on the highway, and traxion and grumpy are probably right up there with him.

SlowStangEater

JP...........300 horses for under 1500 is not likely. Unless you can do all your own work and find some great deals. Besides, once you get 300 horses, you are going to have no traction and thats were it counts. I hate hearing it.....but swapping a 350 is your best best. Its gonna give you enough horses to satisfy you and its best for DOLLAR to PERFORMANCE.

Slade1

As far as mileage is concerned, that's city I am referring to as of late. I haven't tested highway yet (had nowhere to go lately) since the porting and underpulleys and have been doing only city driving (work and stuff). Last highway drive I've done had me doing 120 miles off <1/4 tank and considering my tank only holds 12.5 gallons that's pushing to almost 40 mpg highway. I'll be conservative and say 35mpg though since I was only doing 70 mph. (Yeah I know I got a freaking small tank, but it was reconditioned and baffled at least). I think I could get more out of it if I went to a better coil, rotor, and wires as that is still stock on my car. I think also with a bit more with efficient programming on my chip, since that's stock as well. So as far as milage is concerned I think I can outdo most of you. Now RPM for RPM a 350 with the same ratio and tranny as me will burn more fuel. It's a fact. Anyday a 350 will make more power, but acceleration up, fuel economy down. That is a scientific fact, all laws of physics state when you increase acceleration, you use more force and that uses more fuel to get that force. A 350 gets you more power.

On to the subject of LS6 motor, yeah we know the gearing in the Z06 has 2 overdrives, but I wasn't referring to that in terms of mileage. It will help, but a better designed engine still has better mileage. The LS6 advantage for fuel economy over the previous generation is

Better intake more air flows though that
Better fuel injection
Sequential fuel injection is key here
You can't change TPI's design flaws no matter what tuning you do to the ECM.
It will still shoot fuel for all injectors (8) all at the same time and only 1 cylinder per pulse will be ready for intake, the rest will meet with either a closed or semi-open valve. this is not to say that it won't have a decent amount of fuel per cylinder, it just its not proper timing and that is inefficient and GM knew this and designed its evolution, the SFI.

The air it takes in gets severely heated by the intake plenum. Even with ram air and cold air induction, it still meets up with that problem. Hence ice at the strips for all you TPI users. The TPI was never designed for fuel efficiency, it was designed for power.. raw power. That's why you use it, you never wanted economy when you got it, you wanted power. So be happy with the power you got. A carb has the worst economy of the lot and no matter what you do to that thing, it'll never reach the same level as FI.

As far as the 305 is concerned its an economy V8, the 350 is a power V8. Take your choice. The 305's displacement is only off on the bore vs the 350. The 350 and 305 share the same stroke. All 305's were shafted and got crappy cams, manifold, heads, and headers. The 350's got shafted too, just not as much as the 305 did. This is why the 305 sees boosts as much as 50 hp from a cam alone. This is why a 305 will see 100 hp jumps from an intake/exhaust and cam. GM probably knew they could make a 305 and 350 so close in performance that they couldn't sell the 350 as a performance motor. Take the 305 TPI and 350 TPI, why in ***'s name is there only a 15 ft/lb increase in torque and 10hp gain??? Each year there is a 350 and 305 compare the numbers. Then look at the drop that TBI/Carb gets. That's not solely because of the fuel system, but because of heads, cam, intake, exhaust. When the 305 got the same stuff as the 350 it got a whole lot better. when you build up a 305 and 350 exactly the same, you'll find that the extra 50 cubes aren't worth even 50 more ft/lbs of torque over the 305. In the end a 350 will beat a 305, just not by much.

Ricktpi

It's been stated before & I will have to state it again. The 350 will make more HP & torque for 2 reasons:
1. It can utilize larger valves & have full flow around the valve without shrouding from being too close to the cylinder wall (as in a 305) This is also why 5.0 Ford with a 4" bore will make close to 350 Chevy power.
2.Due to the larger bore on the 350, each inch of stroke will pull more combustion charge than a 305.
The 305 wasn't shafted, it just was never designed to be a performance engine. It was designed to be a low rpm power/ high fuel milage V8, some 26 years ago.
Slade, your "essays" here & on other boards indicate your info comes from reading magazines & not real world experience.

E-Z Rollin

Excuse me! I believe the ? was can I make 300 hp with a 305 for $1500? Not will it be easier to swap in a 350,which seems to b e the pat answer whenever someone ask about a 305. Yes, the 350 in a better bore / stroke than a 305 and should be the foundation if serious hp is a goal,but 300hp is can be made with a 305 for $1500 and yes you will have to do most of the work yourself. Porting a HO set of 305 heads isn;t all that difficult[saves $$$] that can be spent on good cam,exhaust. Also, the TBI setup can be up graded to hp specs, I may have some info on that, I'll check.

SlowStangEater

Ive asked this question myself but Im glad people told me their opinions. I learned lots. This guy is obviously looking for POWER and not Economy. To do all the Bullsh*t with a 305 you have to take the engine out. So while its out why not put in a 350. Im not a fan of the 350 but it does create much more horsepower and its going to give you more power each time you upgrade something than a 305 would. Everyone in TGO knows Im a 305TBI guy.............but the simple truth is that if its cheap power you are looking for then a 350 is the better solution. Its not the only solution..... So its just a matter of what this guy wants.....So by us giving our opinions.........He may find something out that he didnt know and be grateful.

But anyways......I wish you luck with this car and hope you get the power you are looking for........And I hope I get my new rearend soon!.


89 RS ..........Recently rearended by the only Hispanic Guy from Idaho. j/k

TBI305Camaro

id say a set of world heads, lt1 cam, edelbrock intake would make about 300 with a 50hp shot of NAAAWWWW ( ) you will have to have a new chip of course. Im considering just putting world heads, cam (larger than lt1), edelbrock intake and holley carb on mine and maybe a edelbrock n2o kit. That would probably be less work than simply swapping in a 350 and make good power. like i said earlier my car is driven everyday, not just every weekend.

019890Fbird0

What is a LS6 in it slipped my mind in a conversation last night im just wondering

evil t/a

Not even remotely close to being the truth.

A. The GM 305 and 350 tpi's were only close because gm saddled them both with a TPI system made for a 305. And the torue differnce ranges between 35 and 40 ft/lbs not 15.


B. If you do the same mods on both engine the gap gets wider and wider . Do the smae mods on a Ford 302 and a 305 and the 302 will make more power. As someone said earlier the 305 made its displacment in the wrong way , it has the same stroke as a 350 but has a smaller bore , so it cant outrev it because it cant take it enough air. In the end the 350 wins by ALOT.



C. The drivel emminating from the some on TBI board is rediculous and anyone looking for an honest answer should stay away from there.

D. Tpi makes more power than TBI . Period. All dyno , ET , and mph numbers have proven this time and time again. Ask some of the MANY members here that have converted from TBI to Carb or TPI if they are slower than before.

F. 100 hp jumps from intake exhaust and cam on a 305? Bwahahaha , yeah if the intake is a BLOWER.

G. If you want economy buy a 4cyl Honda , in terms of perfomance the economy argument is what ricers fall back on when they know that they are beat at every other angle.

evil t/a

Oh and if every TBI'er that used those links knew the sorce of those links you would feel mighty silly.