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J.D. Jim A 10-24-2004 19:19:34 209.163.43.60 11518 Report to Moderator	Just got a 305 Small Block for a '91 Caprice, Any tips or tricks to get some cheap horsepower out of it? [Reply]  [No Email]
Jegs 800-345-4545 11-20-2004 08:18:05 209.193.79.11 11727 Report to Moderator	Re: More power out of a Chevy Small Block in reply to J.D. Jim A, 10-24-2004 19:19:34   Headers..... yes. BUT, buy a Comp Cam Magnum 270 duration - 470 lift - 224 @ .050 . will really wake it up and not be too much hot-rodish. The cam in all stock motors are a little to wimpy, and the BEST thing to any little small block will be a camshaft upgrade. Good luck.   [Reply]  [No Email]
Ron in Nebr 10-31-2004 22:21:39 65.169.97.32 11583 Report to Moderator	Re: More power out of a Chevy Small Block in reply to J.D. Jim A, 10-24-2004 19:19:34   The other posts were right, there's no replacement for displacement. But since you want to work with what you have, there are some things that can be done. The 305's were underpowered, due to a poor bore/stroke ratio mainly(small bore and long stroke), but also because the bore was so small that the heads had to use fairly small valves and they were shrouded by the cylinder wall. Depending on what year it is(is the motor out of a '91 Caprice or is that what you're putting it into?), the crank could have either a one or a two peice rear seal. The 305 crank and rods would not be any weaker than the same year 350 crank and rods, since they're made from the same material. Granted, they would not be nearly as strong as the crank and rods out of, say, an early 70's 350 out of a Z-28, but they'd be plenty strong for just a mild power improvement. The 305 used the same stroke as a 350, and apart from a slight difference in balance due to the smaller pistons, the 305 crank is almost visually identical to a 350 crank. Since you said you wanted "cheap" power, your best bet is to just do the old standard hot rodding tricks to help it breath better- improve the exhaust system(duals, free flowing mufflers, headers), get more air in(free flowing air filter), and if money allows put in a better cam. Keep in mind that this is a small engine, so a cam that's fairly mild in a 350 might be too much for the 305. Your best bet would probably be an "off-road" or "high tourqe" grind. Be sure to put new lifters on any new cam. Also get a quality aftermarket timing chain, since the stock ones were noted for not being degreed right for best power. If a cam is too expensive, a cheaper substitue would be a set of 1.6 ratio rockerarms. These would open the valves faster and farther than stock and give a bit more airflow. You can also add an aftermarket intake manifold for a bit more airflow, but with the limited amount of air going through the 305 heads this probably wouldnt help as much as it would on a larger engine. Finally, unless it's computer controlled, you can get a kit to speed up the mechanical advance in the distributor, and then also play with advancing the timing a little. Be cautious here though, since the 305's had a tendancy to be prone to detonation, which will kill it fast. Remember, regardless of what size it is or what brand, an engine's basically just an air pump, and anything you can do to help get air into and out of it easier will make more power. Also, and I havent yet mentioned it, if you get alot more air goint through the engine, you'll also need a corresponding increase in fuel, which means richer jets if you have a carb or playing with the computer if it's injected.   [Reply]  [No Email]
Gene Davis (Ga.) 10-24-2004 22:23:18 66.82.9.30 11520 Report to Moderator	Re: More power out of a Chevy Small Block in reply to J.D. Jim A, 10-24-2004 19:19:34   Cheapest way to get h.p. out of a 305 is to trade it for a 350! These engines aren't noted for anything great in the way of performance in this neck of the woods.   [Reply]  [No Email]
Jon H 10-25-2004 14:53:45 69.26.17.115 11526 Report to Moderator	Re: Re: More power out of a Chevy Small Block in reply to Gene Davis (Ga.), 10-24-2004 22:23:18   I think Gene is right,the best way to hop up a 305 is to replace it with a 350. I have read several hop up articles saying that a 305 has lighter duty crank,rods,pistons than a 350 and do not live long if pushed harder than stock.   [Reply]  [No Email]
J.D. Jim A. 10-25-2004 18:29:21 209.163.30.30 11527 Report to Moderator	Re: Re: Re: More power out of a Chevy Small Block in reply to Jon H, 10-25-2004 14:53:45   Yeah, that's true, but I've got the 305. Any tricks?   [Reply]  [No Email]
db 10-25-2004 19:25:50 205.188.113.6 11528 Report to Moderator	Re: Re: Re: Re: More power out of a Chevy Small Bl in reply to J.D. Jim A., 10-25-2004 18:29:21   Hi, It depends on how much you want to spend. The easiest way is to put a set of headers on it. Then easy but quite a bit more expensive is a higher performance aftermarket carburetor. Something cheaper than a carburetor, but more work is a higher performance camshaft. In the later 1980.s they chenged to roller lifters, I had them on my 1988 305. But the others are right about the strength of the engine, especially the crankshaft. The crankshafts are nodular iron, but there are steel crankshafts that are better performance. The crankshaft will be harder to find because it is the one piece seal. There are aftermarket crankshafts like Scat or Eagle to look into. The 305 is low on power, but when I went from a Plymouth minivan to a 1988 Caprice I was used to flooring the gas pedal on the Plymouth and waiting for the squirrels to start running in their drum, well, I floored it, and shot across an intersection when I meant to turn left. Fortunately I was the only one there. But they don't live long when they work a lot. A year after I got the car I got a 5 by 8 utility trailer and started hauling scrap metal. It didn't take long to wear out the bearings. I rebuilt the engine, and it took about a year to need another crankshaft, and insteqd I got a 1975 GMC one ton with a 350. The GMC has enough to do what I want. To make a long story short, it should work good for driving as a passenger car, but don't expect it to be a truck. I would start with a set of headers, and maybe dual exhaust and a pair of mufflers that will make it breathe a little easier, and maybe sound a little better.   [Reply]  [No Email]
Jon H 10-26-2004 11:30:22 69.26.18.52 11529 Report to Moderator	Re: Re: Re: Re: Re: More power out of a Chevy Smal in reply to db, 10-25-2004 19:25:50   I agree with db,a set of small primary tube street headers are about the most bang for your bucks. A little more torque and HP plus a good chance of gaining a bit of fuel economy. With a non electronic carb you may have to rich up the primary jets/metering rods 1 step richer,as headers tend to lean out the mixture. If fuel injected or electronic carb,make sure the header has provisions for the oxygen sensor.without it your mpg will go way down. also if the oxygen sensor is the 1 wire type and has 50,000 or more miles,replace it. I just replaced the dead oxygen sensor on a 92-454 pickup and gained nearly an extra 100 miles per tankfull with a $20 0xygen sensor. When they die they tell the computer to go to the full rich setting.   [Reply]  [No Email]