have 305 NEED MORE POWER

i have a 1983 Caprice Classic 305 and this car in general is pretty weak. Is there any cheap way to get more HP? The only thing i can think of doing that is somewhat cheap is to put in a true duel exhaust or a racing cam of some type. Is there anybody that has done either of these two things that can tell me what type of cam or exhaust they used? Even better can anyone recommend anything else i could do that would still be fairly cheap?

Niether of the above will really help. The problem is low-end - the 305 really doesn't have much. It can be made to, but a 350 can be made to make the same power for less $$$.

Even a completely stock 350 will have a very significant difference in power and accelleration. Gears wouldn't be a bad idea either.

Niether of the above will really help. The problem is low-end - the 305 really doesn't have much. It can be made to, but a 350 can be made to make the same power for less $$$.M

alright so now that im sure the 350 would make a significant difference. how much would a 350 swap cost "i'll do the labor myself" and where could i get one. Most importantly will there be a need to buy any new components "like an ecu" also?

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alright so now that im sure the 350 would make a significant difference. how much would a 350 swap cost "i'll do the labor myself" and where could i get one. Most importantly will there be a need to buy any new components "like an ecu" also?

Depends on where you get a suitable used engine. If you live near an Ecology or a Pick-n-'Pull, you can get the entire engine including the belts and what the belts drive, for less than two hundred, provided you pull it.

As far as the ECM, since your engine is carbureted, don't worry about it. My police package came from the factory with a 305 in it. I installed a 350 out of another car I had, dropped it in and ran with it. Over 3 years and 60,000 miles later, the 305 ECM is still running strong. You might find a little better performance with a 305 carb ECM running on a 350 - due to the fact that the spark advance curve tables are a little more aggressive on the 305 ROM.

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Your 1983 should have a TH700R4 in it if it's got OD, or a TH350 if it doesn't. In the case of the TH350, you don't have to worry about the 350 as the tranny will handle it just fine. With a 700R4, I'd get a suitable donor transmission from a newer car (1987-1993 TH700R4/4L60 - not 4L60E). If your car has a TH350, you might want to consider the newer TH700R4/4L60 just for the economy. If you do wind up going from a TH350 to a TH700R4, you will also need to get a suitable driveshaft and crossmember.

At one of those junkyards I mentioned, you can get the entire outfit for less than $400.

I was considering doing a 350 swap eventually, being as how the 305's dont have that much power potential, but i dont want to decrease gas mileage

You can actually make a 305 go if you're willing to try aftermarket heads (such as the World Castings S/R Torquer 305 heads) and some cam and exhaust upgrades. It is, after all, a Small Block Chevrolet and it will respond to Small Block Chevrolet upgrades.

The point is, a 350 can respond to the same mods and get more power. However, a 350 is about 5% less efficient than a 305 in the same car, from an economy standpoint. This may or may not matter - in my case, the lower MPG was a tradeoff well worth it from a power standpoint.

I'm considering a compromise on my next build, however -

I'm thinking that the engine to replace the 350 in my 9C1 will be an updated, fuel injected 327. Should be about the same power-wise as the engine I have now, with the economy benefits of 23 less CID and EFI.

Added that if I came across one relatively cheap, the new (in a manner of speaking) LS-series Vortec 325 (5.3) is a screaming powerhouse in stock form and that would go over very well in my car.

I like the idea of vortec, I've tossed that idea around in my head a few times.... could aftermarket (or even stock) vortec heads be installed onto a a '92 block and successfully use the same 1992 if I could find a manifold to fit the votec head geometry TBI? Also how do vortec heads do with a supercharger... I'm still kind of hanging onto the whole "blown" engine idea for the future.

Two different types of Vortec engines here - the one I am referring to is the LS1-based Gen III engine, the one you're thinking of is a Gen I or standard small block. Those cylinder heads will bolt right on any old small block, the only thing you'd have to worry about is the intake. However, there is a good aftermarket for intakes for those heads - you can even get a carb intake for them that allows you to retain your standard ECM setup. A full-bore Vortec 5.7 will require its OBDII PCM.

Would vortec heads with a stock OBD1 ECM and stock (or even modified) TBI even be worth it? How much of a power difference could there really be?

The issue is whether or not they make an L03/L05 style intake that works with Vortec heads. If they do, then you're home free. I do know they make a Vortec intake that works with the carb and distributor that I have, such that I could put a set of Vortecs on my own car if I was so inclined (and I just might be).

The Vortec head generally has the same flow characteristics as the cast iron LT1 head, but can be used on older small blocks (whereas the LT1 head only fits LT1 or L99 blocks). How much power you gain from them is subjective - many factors so I can't tell you how much you will pick up, but you will pick up top end.

Well, I guess thats something I will have to research when the time comes. Until then, a bone stock TBI 4 bolt 350 it is. Hopefully the dual exhaust and headers will at least give me a few more ft/lbs.

maybe a dumb question, but is it possible to put a supercharger on these engines?

Of course, but if you leave the engine stock it will drastically shorten it's life.

i have a 1983 Caprice Classic 305 and this car in general is pretty weak. Is there any cheap way to get more HP? The only thing i can think of doing that is somewhat cheap is to put in a true duel exhaust or a racing cam of some type. Is there anybody that has done either of these two things that can tell me what type of cam or exhaust they used? Even better can anyone recommend anything else i could do that would still be fairly cheap?
this is a good engine for this vehicle wt. but the exhaust and air intake is restricted. with cat removed and dual exhaust installed at a custom exhaust shop with cherry mufflers and a larger air intake on the carb with ram air then adjust the transmission detent cable for less downshifting on the highway you will soon realize that you need rear stabilizer bars. also make sure that the fuel pump and small gas fiter in the carb is replaced. this has been a problem rust in fuel restricting gas flow....

Niether of the above will really help. The problem is low-end - the 305 really doesn't have much. It can be made to, but a 350 can be made to make the same power for less $$$. You have never removed the stock exhaust and installed duals, cat removed, obviously. I have in this year, model, it is a huge difference.

You have never removed the stock exhaust and installed duals, cat removed, obviously. I have in this year, model, it is a huge difference.

I am so glad that you know more than someone who has been building race-ready engines for over 20 years now. I never would have otherwise known.

I will not apologize for my sarcasm, and you're going to find this reply to be rather harsh toward you.

First off, let me educate you on something. An engine is a big air pump. Airflow on the engine is what determines the power - airflow potential is determined by valve size and timing, as well as port volume. Guess what? The single exhaust these cars come with is optimal for the airflow potential of the stock 305! In fact, it's overkill!

You go throwing duals on the car without increasing airflow potential, and low end torque suffers as a result.

You go taking the cats off that thing, and don't ever drive it near me. First, I don't want to breathe the polluted air from it, and secondly I am bound to turn you in to the federal EPA. Guess what? That can cost you $25,000.

If you want to do it right, you install a bigger* cam, and better flowing heads. You then turn to the intake, and then to the exhaust. Keep it reasonable - too much and performance + economy goes south.

In the end, you're deluding yourself if you think that simply throwing on duals increases performance. It may make it sound better, but duals in and of themselves aren't worth much without the aforementioned upgrades.

Now, before again coming off with that condescending, know-it-all attitude, it would help to know more about what it is you're talking about - both on your standpoint and mine, before opening your mouth (or fingers in this case).

*Keep the cam size realistic - this is one way you can have performance surely hit the floor. At least it'll idle nice!

this is a good engine for this vehicle wt. but the exhaust and air intake is restricted. with cat removed and dual exhaust installed at a custom exhaust shop with cherry mufflers and a larger air intake on the carb with ram air then adjust the transmission detent cable for less downshifting on the highway you will soon realize that you need rear stabilizer bars. also make sure that the fuel pump and small gas fiter in the carb is replaced. this has been a problem rust in fuel restricting gas flow....

Thanks, thats really gunna help out later on when i get the money. I dont think i want to spend the time experimenting with a whole engine swap so now i know where that moneys goin. I just wanted a little more hp but while keepin it cheap and easy at the same time

A reasonably good way to get a power an mileage improvement is to increase compression. The 1983 305 likely had dished pistons, 64cc or larger heads, and a static CR of around 8.0:1. If things are really going badly for you, they might even be '997 heads with 76cc chambers, delivering a paltry 7.75:1 static CR. The original cylinder head castings on your engine were likely either the '997s, '801, or '807 heads.

With a functioning EST and fully functional E4ME feedback carburetor (the one that came with the engine) you should be able to use regular grade gasoline at 9.5:1 static ratios with no problems. If you remove a rocker cover and look between the rocker arms, you should be able to find the head casting numbers. If they are not either 14022601 or 14014416 castings, you may be able to make improvements with stock cylinder heads. Both of those heads have smaller chamber, and the '416s have much improved ports, larger intake valves, and improved chamber designs. If you can find a pair of those, freshen them up, and install them on your engine, you will at least have valves which seal, guides which don't leak (for a while), springs with the proper seat pressure, and the potential for both better flow and improved fuel mileage.

14014416 305 HO, 80-85, 58cc, 1.84-1.5, 165/59cc ports, 7 bolt ex.
14022601 267, 305 HO, 80-85, 58cc, 1.84-1.5, 7 bolt ex.

Even with dished pistons, the '416s will bump your static compression ratio from 8.0:1 to 8.6:1 If you are lucky enough to discover '997 heads with flat-top pistons, the CR will bump from 7.75:1 to 9.3:1. That would make some significant power and mileage increase.

Before you go crazy looking for heads, however, check to see what's bolted to the engine now.

i have a 1993 caprice 305 still low on miles and isnt too bad on power, but when i put a 1996 impala rear end (3.08). I ran one of my buddies that had beat me by about 2 car lengths when i was stock, and with the impala rear end i got him by a good 2 1/2 or 3 cars. And that was only about 300 dollars out of my pocket installed