Rgeddes09

I posted this in the engine swap forum, but I think this is a more fitting place for it...:

Has anyone read this article? I am looking to milk some more power out of my 89 TBI 305 camaro for something in the neighborhood of $2000. I was doing some research because I don't know much about engines (yet). Does anyone have any idea how much this would cost and how much time it would take realistically?


http://www.popularhotrodding.com/eng...cks/index.html

150 HP for a 305 Chevy Engine - Hate Me

Add 150 HP to the Chevy No One Likes
By Steve Dulcich


I'm not sure what's tougher, being a 305 Chevy, or being a 305 owner. It's all abuse and insults, and never any respect. Talk about building or hopping up a 305 and guys will generally shun you, or even boldly accuse you of being a fool. You'll hear, "Why mess with that junk motor? You're wasting your time." Wouldn't it be nice to lay waste on their stuff instead, with a few discrete bolt-ons? How about a bolt-on package that will add 150 crank hp, and still pull a good 13 in-hg of manifold vacuum at 850 rpm? And what if all the stuff comes in cheaper than what it would take to build the average high performance 350 short-block, and all the parts will transfer over to a larger engine and work great if you ever decide go bigger? We know there were tons of 305s built in the 1970s right through to the mid '90s, many of them in cars with definite performance undertones, most notably GM F- and G-bodies. We'll go out on a limb and presume that there are quite a few of these guys on a working man's budget who'd love to spring for a fresh up-sized engine, but have to make do with the 305 that's in it now.
No engine modification effort will be successful without giving it plenty of thought and planning. First, we really had to think about why the 305 has such a reputation as a pooch. We deduced right away that all of these engines were built during an era when horsepower took a back seat to other considerations, and were generally choked with all sorts of add-on emissions do-dads. Factory 305s came with anywhere from a low of about 130 hp, to a high water mark of 230 hp for the hot Camaro LB9 injected engines in 1990. Most 305s made right around 140-150 hp as the factory net rating, and that isn't the kind of output legends are built on. We also identified that the engine is small, and has a particularly small bore at 3.736-inches, while the stroke is the same as a 350 at 3.48-inches. The small bore is an immediate red flag to most guys; but is it really when things are looked at in proportion to the engine's size? In fact, the factory 305 bore/stoke ratio is actually slightly better than a stock 454 Chevy, and way better than any of the 4.030x4.000-inch strokers. Conjuring the Power Pack Actually, with the right heads, there is nothing inherent in the bore to stroke ratio of an engine of this displacement that will cripple cylinder filling, especially in the street rpm range of under 6,500 rpm. We had just the heads in mind for this project, the 180cc intake runner EngineQuest (EQ) replacement Vortec castings. These heads are machined for 1.94/1.50-inch valves, which are proportionally large for a 305-cube engine, and their low cost makes them a natural for a budget conscious 305 build. The flow of these castings is a major step up from restrictive stock 305 heads, and we have seen firsthand that they can support excellent output, even on a larger 350-cube engine. On a 305 engine, their 233-cfm of intake flow, if taken in proportion, would be the equivalent of running a 290-plus-cfm head on a 383 small-block combination. Our 305 should be more than happy with the flow these heads provide.
Shaver's Specialty Service supplied the EngineQuest cylinder heads, which retail for about $225 each as bare castings. We had Shaver's mill the heads a modest 0.030-inch, to reduced the chamber volume to 60cc, so that we wouldn't lose compression ratio compared to the typical production small-chamber heads used on these engines. Shaver's assembled the heads with a budget 1.94/1.50-inch valve combination, along with convention single performance springs with dampers. Later in testing, we wished we'd stepped-up to Shaver's extra-cost COMP No. 26918 beehive spring package, which would have allowed even more rpm, and possibly allowed the engine to make more peak power.
The cylinder heads from Shaver's were the cornerstone of our 305 modification plan. Besides the heads, we only intended a few other complimentary mods, intending to use a factory 305 short-block for the testing. Our 305 test engine had been stashed unused and unloved on a pallet rack at Westech Performance Group for years. It wasn't until the casting numbers at the back of the block were verified that they were even certain of what the engine was. It took considerable persuasion to build enough enthusiasm in the Westech crew for them to even consider forklifting it down. It turned out to be a low-end 305 with dished pistons and a regular flat-tappet cam. Some of the high-end 305s came with flat-top pistons for more compression ratio, as well as factory hydraulic roller cam setups. Our engine isn't ideal to show off the 305's potential, but if nothing else it does represent the typical 305 that people love to hate...(continued)

SeanW

If i was putting money into a 305 i would do so looking at parts i could later move to a 350. You can't really do wrong with a good set of heads and a cam swap.

bakes85

its amazing the amount of horsepower you can get out of an engine for a budget

I was just reading a car craft article about getting 500 HP out of a 350 for like 3 grand or something like that.

I would say just do some research and start with doing some little things.

Timinsk

iTrader: (9)

i was curious on this article too..

Rolling Thunder

Really the same basic ideas that apply to 350s apply to 305s. Getting 370 hp out of a 305 is doable as they proved. As you can see they made gains across the board from 2600-6200. However what happens below 2600 is what ide like to know. Reason is street ability. Tamer parts will lead to more low torque and on the street thats what you really want. To really explain why looking at physics for a moment Force = mass X acceleration re arranged this is acceleration = force/mass so as you can see the greatest acceleration (what gives you the feeling of being pressed into the seat) will be increased by increasing the force or decreasing the mass. Now a radical build like the one shown in that radical will decrease low end torque. Although even something like 25 ftlbs may not seem like much when you multiply that out by the gear ratios it becomes a large sacrifice at the wheels which in turn lowers the acceleration in the low end where you typically are on the street. For racing yea peek hp numbers are great but for everyone else not so much. Now you might say that when you look at there graph they made improvements all the way across the board but again if you built it differently you could make much stronger gains in the low end. Then theres the fact there peek hp was at 6.2k rpms who runs up that high on a factory motor? Again because you max RPM is like 5.5k you've sacrificed some of the lower end gains you could have had to build power at an RPM you cant get to. Then there's legality to consider some of those parts at least are not legal for street use in your car. Long story short although you could replicate there build and i agree with alot of the parts they chose i wouldnt build a motor like that for street use. How much it would cost to do? That varies by where you get parts and who does the work ect. Although all the parts are easily accessible from places like summit racing so when you decide what you want you can simply look up the prices. With 2k you could do a lot on a budget build like new vortec heads cam intake probably even a set of headers. Although again i wouldn't replicate that build personally.

bakes85

yeah, thats the problem with these type of builds, they aren't very tame or stable at idling from what I have read.

Rolling Thunder

Yea thats the issue with a lot of magazine builds. They look great on paper but not so much in practice for your average joe. Unless your really experianced in the matter you dont really know what to expect and the magazines I dont think really go into that enough. Course then again if you were really that experience in the matter you probably wouldn't be getting you builds from a magazine then either. That being said its not really there fault. I mean who would be truely interested in reading a article about a 280 hp 305? I know i wouldnt flip and pick up the nearest copy lol. That being said though a lot of thoes kinds of build will leave u with a car thats more fun and "feels" faster due to the greater low end torque. Best of all it could be very pratical as high performance dosnt necessarily mean bad gas mileage and even street legal.

ScorchedBird12

What would happen if I ran this with a TPI setup? I noticed they ran a carb.

Fast355

iTrader: (2)

Apparantly you don't race much. I have run stock lower ends well up over 6,000 RPM and the only failure I have experienced yet is a spun rod bearing in a chevrolet 305 with 200K on it at the time. Even my 5,600 lbs dodge ram only spends a moment under 2,500 rpm when you really lean into the throttle. The stock torque converter stalls around 2,400, the truck leaves a touch soft, but any more torque to the wheels would just make it that much easier to spin, however the bulk of the power is between 4,500-6,500 on this truck and it is well into the 13s in the 1/4.

http://www.youtube.com/watch?v=nlDqoeayqBI

http://www.youtube.com/watch?v=uEvDiVKZ_1Q

Torque gets you moving, HP and Gearing is what makes you run down the 1320 well.

freaky

the only time my car is under 2500 rpm's is cruising down the interstate .(1850 rpm's @80 mph ) i shift mine manually around town an on back country roads . i try to keep mine in the powerband of the motor . overdrive is for the highway ! i'm sure somebody's gonna say that shifting manually will tear up a tranny but i been beating this 700r4 completly stock tranny ( 169000 miles ) like this for 3 years an she's doing fine .