I have a stock 305 with carb injection. My question is I am wanting a 3-400 hp car without nos is this possible with a 305, and what is a rough estimate on h o wmuch it would cost and would it be cheaper for a 350 thanks.

 

Talk to TOM84L69..if you can get a hold of him he has a 305 with a litle work done to it mostyl stock that has 300-325 horse. he ported and milled the heads put headers and exhaust and a BIG cam. IT is better to do a 350 but then you have to do a motor swap.

 

ok thanks alot yah i want a 350 but i cant exactly go out and buy one "money is tight" so i thought if possible id supe up my 305 and get nos .

 

Check out my post "We all know 305's can't run".

Obviously, I'm running a 305. On desktop dyno, it equates to about 360 HP @ 6000 at the crank. That's with CC carb, and a cam that won't send it into fits. I have yet to hear of anyone achieving 400 HP out of a CC 305 without spray.

Reality is, it is cheaper to get 400 equines out of a NA 350 than it is getting it from a NA 305. You don't have to get as wild with the 350 to get the same total output because the HP/CID can be lower. And, high-po 350 parts are cheaper than like 305 parts - and better stuff is out there for 350's.

I will say you can have a 305 that will outrun equal money spent on a 350. But, that's only because the things that make the 305 run better would also be required to make the 350 run better. At a certain point, though, the 350 starts to take over (I'm probably at that point).

 

yah well i was thinking I can always sell my 305 to someone down the road, Im just getting into cars erally so i thought of just trying to build up what ig ot first mainly to play around witht he kids here who think they got fast cars but i do have around 900 to spend on it so i though i could atleast get 300-350 hp shoul dbe better than 170

 

$750 for exhaust (you need it from the heads to the rear bumper), $135 for a computer compatible cam & lifters - you've spent all your money (there's always things like gaskets, hoses, antifreeze, etc., that you need when doing a job like this, too). You haven't touched the heads, and you at least need new valve springs. If you don't have to worry about emissions, you can save a few bucks by getting non-emissions headers and no cat, but that won't be enough to buy heads (although you might be able to do a home porting job on your stock heads - don't forget you'll need to have the valves ground when you're done, perhaps guides as well).

I'm not trying to discourage you, just understand what you're in for up front. Exhaust is a must-do, cam is a must-do, valve springs must go along with cam - but 300 HP isn't a reasonable goal for $900 and a 305. "The power is in the heads" is often repeated on these boards, and those alone is close to your stated budget.

 

What if i were to supercharge it/ Exhaust and other minor stuff how muchw ould this give me?

 

T bird,

You said you're on a tight budget, but then you're throwing around superchargers and such.....those are big bucks to get it done right.

Car craft did an LG4 build up (wimpy 305) and did get 400 horsepower. I also have another link at home where someone got 400 horsepower out of a 305. Where either of these very streetable, not really.

The car craft project did it without NOS, but they bumped the compression up to something like 10.5:1 by replacing the pistons, they took a set of Vortec heads and had them milled, slapped a Victor Jr. intake on there (single plane, NOT streetable), had hook supercompetition long tube headers, no cat system, and a fairly large cam.

They spent about 2 grand on the engine, which isn't too bad, but they of course had all of the equipment and tools to do everything themselves. That car would NOT be street drivable. Ever try driving a car like that on the road.......it sucks!

There are a couple of 305's on the message boards here that are getting ridiculously huge amounts of horsepower. Look up Willie, he's a moderator on the History/Restoration board. His 87 dynoed around 460 rear wheel horsepower, passes emissions, and is a daily driver. It's taken him a lot of time, effort and I'm sure $ to accomplish what he's done. It's nothing that he's just thrown together like you're suggesting you'd like to do.

What year is your car? That's a good place to start.

 

guess ill save my money just wanted to know how much a 350 is gonna save me in the long run...........

 

I thought that they only got 330hp out of that test.

http://www.fl-thirdgen.org/325-305sbcbuildup.html

 

Iroc,

My BAD! You're right. I must have gotten the two of them mixed up. When I get home I'll post the link to the 400 hp build up. I was thinking of one and writing about another.

I used to have a link to a site where someone had scanned in the article that Car Craft did, but the link doesn't work anymore!

BUMMER!

Point still is, and this is a highly debated subject....if you already have a 305 in good condition, and you're not looking to build a 400 hp monster, you can get it done cheaper with the 305---because you're saving yourself the cost of buying a new block! Now if you have to start from scratch, might as well start with a 350.

But you've already got a 305......exhaust, ignition, intake, carb (induction), cam and heads. Same formula for any car. Then you work on suspension.

I've done mine a little backwards....I've yet to slap on an exhaust system. All I have is a Flowmaster muffler and everything else except for heads!

 

i'd like to know what would make you think it wasn't possible to make 400hp out of a 305.

 

Nobody said it wasn't possible. The two things that were said were: 1) Haven't seen it done with computer controls (w/o power adders); and 2) the results aren't very streetable.

 

I believe that 400 hp 305 was with AFR 190's, a carb, and like 224/230 cam or bigger. No where near a street engine and the stock bottom end failed during the dyno tests. I'm sure someone knows that link, it has 3 build ups on it for 305s.

 

since we got the topic of 305 buildup i am looking at the same thing but am more or less looking at NOT getting 300HP but make the car quicker while adding some horse power.
Right now i have a 305 with a 4 barrel Carb, stock 2.73 gears, stock exhaust.....the engine was rebuilt 14 months ago (about 12K miles) with stock stuff as far as i know cause i was really tight on money
Currently i am looking at Edelbrock headers, hooker cat back, and a high flow cat....
I am also kicking around the idea of putting in a posi with 3.42 gears
i guess im running roughly 190HP stock, how much more will headers and the new exhaust give me? and a K&N? i have had some people tell me it'll be a noticeable amount of 20-30HP and other people have told me it won't help me much unless i do work to the engine. Will an open air element or dual snorkle be worth the hassel and cost to put in? (all of this i would be doing myself so cost is strict parts)
now the gears i was told that 3.73 was too big for what my engine is producing and 3.42 would be better and my differential is a stock non-posi POS so is the posi and 3.42 gears compared to the 2.73 gears going to make quite a big difference in speed with the added power from redoing the entire exhaust and possibly dual snorkle and K&N?
the posi im looking at is an Auburn posi unit 26 spline, is this a good unit or should i go with an eaton?
I'm looking to spend less than $1000 on all this and from what i can tell this is the best for my limit and i am going to see about installing the differential and gears myself otherwise that right there is $1000 without even touching the exhaust.
if someone could answer any of my many questions here it would help me out a lot and im sure it will also help out TBird get started since he's on a budget as well.
I'm not looking to push 300horses but what i'd like is a noticeable and measureably faster car.....right now a mustang GT takes me to town cause im all bone stock...a friend of mine has a 67 mustang with a 289 and 3.55 posi rear and smokes everyone but the 4th gen camaros, he also has a cat back exhaust, im looking to get somewhere close to this (his engine is stock although he did get a better carb)....ah by the way its a daily driver but i dont think the 3.42 gears will kill my gas mileage too much or at least not as much as the 3.73's

thanks for any help or suggestions
and Tbird i know how you feel

 

Here is the link that I think you are looking for, has various build ups for the 305 TBI. At the bottom of the page.
Buld up

 

well nos will help to so i guess ill get a 75 shot i found it for 400 bucks

 

here is how to make 400 hp from the good old L69 .. (All gm crates should be named after sex acts .. haha )

 

Try here http://www.angelfire.com/nb/thirdgen/tech.htm

It tells how to get some ponies from a mule motor.

 

five 7 kid. read the post topic and read his question. he wants to know if it is possible and i'd like to know why he would have the idea it wouldn't be. btw tbird, what is carb injection?

 

desktop dyno tells me 379hp at the crank with my config

 

Whoever was responsible in the making of Desktop Dyno should be shot.

 

Sometimes the question not asked is the one that really needs to be answered.

There was no talk about this being a show car or strip-only car. From the dialogue, one can easily conclude we're discussing a daily driver here.

"Carb injection" is what a guy who admits he's just getting into cars says when he means "carb induction".

Those who take the results as gospel need some learnin'.

Taking the results, multiplying them by .8, plugging that into Drag Strip Simulator produces times fairly consistent with what we run up here.

 

These programs are only as smart as the people who develop them.

With desktop dyno my car should be making 340hp at the flywheel sure