I origionally wanted to swop my 305 for a 350, but the guy I bought the engine from took my money and ran. Now I am limited on the amount of funds I have available to me. I was wondering about doing a performance rebuild on my 305. Would it be cheaper than a new 350? and could I get good performance out of it? What are some things I should look at doing and how much do you think it would cost?

 

If you have to touch the short block (boring, pistons, things like that) it costs about $50 to change to a 350. There's no sense whatsoever in doing all that to a 305.

If all if that is OK, then go ahead and mod it; heads, cam, intake, exhaust, etc. are all about the same cost and all that as a 350. All of them interchange. Plus, alot of what that car needs, isn't in the engine anyway, and it would need it whether you put a 350 in or stay with the 305; total exhasut system fromt eh heads to the street, gears, converter, suspension work like subframe connectors and LCA lowering brackets, stuff like that. In fact if the existing engine works, I'd recommend spending your money on that stuff and just leave the motor alone for the time being.

 

The 305 it has is a slow 170hp. I was hoping to get closer to 300hp. I figure if I use the block I have I wouldn't have to spend the money to get a new block. Saving me around $300. I have heard there is really not much you can do to increase power in the setup I have unless you change the block setup itself. Exhaust and bolt on stuff doesn't help much in this car is what I have been told many times.

-Joel-

 

That's not strictly true; it's just that it takes an AWFUL LOT of bolt-ons to cure the weaknesses of the car as a whole.

People have a tendency to think "my car's slow, others of the same make and model but with a different motor are fast, I see old Billy Bob over there has {list motor specs here}, must be that everything under the hood has got to go, I'll build a monster motor and slap it off in there and I'll be fast". Wrong. When you start out with a car that was basically built as a gas-mileage grocery cart sacrificial lamb to CAFE, there are all sorts of things about the CAR AS A WHOLE that ultimately create obstacles to improvement.

It's a bad car (or at least, not as good as some others) to start out with as the platform for a "bolt-on" faster car. It has terrible gears and needs a torque converter desperately if it's an auto. Gears are not cheap, if you have to pay somebody to install them for you; and neither is a torque converter.

You'd need gears and a converter no matter what motor you put in it. You could put a solid-roller-cammed 572 big block in it, and you'd still need gears. That's what I mean about the CAR AS A WHOLE: a whole lot of stuff that isn't big and shiny and on top of the motor for all your friends to oooooh and aaaah over when you pop your hood, are in need of upgrades. Expensive upgrades. And the car needs them badly, such that bolt-ons are of highly limited value until you do them.

That car needs, in order of importance: exhaust, from the heads to the street, BUT NOT FOR L03; gears; a cam; heads; and chip work. Somewhere along the line it needs an air cleaner, and a torque converter about at the same time as the cam and gears if it's an auto.

The correct way to mod a CAR (not just a motor) is to identify the ONE thing that is the lowest limit to its performance. That is, the first "ceiling" you bump into while trying to go faster. Once you identify it, choose an upgrade to it that makes sense in terms of your goals and budget. Then once you do that, you'll bump into another "ceiling"; identify and upgrade that one. And so on. It is NOT to un-bolt and re-bolt big shiny things that sit up on top of the motor out in the open where everybody can see them; it is NOT to get out your Jeffrey Dahmer saw and your dykes, and start hacking wiring and hoses and A/C off of it; it is NOT to look around and see that old so-and-so has a tunnel ram and 2 4 barrel carbs on his car, and go out and buy a tunnel room and 2 4-barrels. The only way that those things will make your car any faster is by making it lighter; specifically, the driver's wallet will have experienced weight reduction.

 

RB nailed it on the head. 300hp is doable with a 305 TBI but it every part of the motor and car need attention as described above. Suspension and drivetrian aside, since these are a given, you will need to replace everything but the shortblock to achieve your goal with the 305 TBI. I would look into chip burning immediatly. If not, your mods past "bolt on" stage will leave you

 

What about this idea... Since I have to burn a new chip anyway what If I got the new LS2 Engine? How much would one of those cost? Less than $1,300? Probably not huh?

Yeah, I was planning on redoing the heads, exhaust, pretty much everything about the engine. then burn a chip. Don't ever buy an engine from a guy named Lackey on Ebay. He will Steel your money like he did with me. little stinker.

-Joel-

 

Just burn a new chip. You are looking at a $10,000 and up swap if you go with a new LS2. That is you doing the work yourself by the way.

 

OH, maybe that's not such a good Idea. What do you think it would cost to take my 305. clean up the cylenders, replace the heads with higher compression ones, new Crank Shaft, and a New Exhaust from the block to the street?

-Joel-

 

Leave the cylinders and crank alone; on the other hand, other heads and an exhaust are a GREAT idea.

Once you touch the cylinders and crank, it makes no sense to spend that money on a 305 short block; basically, your 305 stuff is just a "core" at that point; a 350 core is about $50, maybe $100. Why spend $2000 on a 305, when you can have 45 more inches for $50?

 

Just go grab a 350 shortblock out of the junkyard or something for like 50 bucks, then build up a new motor. Your 305 runs fine right?

Just save up money and build a 350, that's what I would do.

But in the mean time at least take care of your exhaust, it will switch over to the 350 anyway.

 

Im in the same problem i have a LG4 which i have already swapped out the intake manifold, the carburator and distributar making it no longer computer controlled, i have headers and exaust..and now she is running low 14's but im trying to decide if it might just be cheaper buildig a short block 350 and reusing the same aftermarket parts i just bought(to same money) before i spend 2k on rebuilding heads, new cam and seals. last think i wanna do is dump money in the top end and blow a rod out of the bottom end........i feel like i should just start fresh

 

I am taking my 305 and rebuilding it. I am porting and polishing the heads now. I have gone to 1.94 intake valvle fromthe stock 1.84 , a new crane cam (more aggressive than stock) new pistons stock and new headers and catback all this= about 280 to 300hrp and have done this for about $1000 US. It all depends on what u want out of your car. I am not racing just wanted a little to give the next mustang that pulls up thinking his car is soming other than a ford. Again I Will not pull low 14's put i will have better than stock for a minmal price.

 

Hmmmmm.... $1000 for 280 HP with a 305, or $1050 for 330 HP with a 350.... and 320 ft-lbs of torque with the 305, or 380 ft-lbs with the 350 as well..... man, I'm really struggling here....... mind if I step outside and consult my financial adviser, so I can figure out which one is the better deal? I'm not sure which one gives me the greater amount of power for my $$$$.

Build yourself a 305, and more likely than whatever it was you were trying to say about Mustangs pulling up, you'll just end up getting your a$$ handed to you; and then that 305 won't look like such a smart decision after all. You'll just be reinforcing the opinion that exists in the world at large, that 3rd gen Camaro/Firebird is just slow.

Building heads is a good idea. Building a 305 short block is not. Take it from me, I did it, and kick myself every time I drive my car now; if I had known then what I know now when I was building it, it sure as hell wouldn't be a 305 today.

 

I built my 305, its my first car and was my first motor build at age 14, it was a great learning experience, learning how to build a motor..although I would do things differently now. My plan calls for a nasty carbed 383 in a few years or so.

But I am still going to mod my car to its fullest extent to see what I can get out of it. It's a fun car and thats all that matters!!!

If you have a chance to go 350 then do it!

 

First of all u Are right about doller for doller the 350 is a better motor for the money. I did not mean to dispute that.. or anything else for that matter. RB I would never go against any advise that u would give. I have read alot about your advise and have found all of it to correct and trust worthy so don't think I am challanging your expertice. I was slimply stating if a person is not looking for the big horse power OR TO UPGRADE to big horse power a person for litlle money can make the 305 respectable.
As far as the tangs I think u give them more credit than they deserve. With my stock 200hp I held my own with them.
Any ways RB I love u man:hail: :hail:
Kelly

 

Thank you!! I try very hard to be honest, and to help people who don't have the BTDT just yet, to avoid the mistakes I've either made or seen others make, during the time I've been participating in this hobby.... which is longer than a majority of the people on this board have been alive. I don't claim to "know everything", but I've ssen ALOT of mistakes, and ALOT of how Not to make them; and believe me, it was ALOT harder to avoid them, back before we had the Internet. Newcomers to this hobby (and most others too) don't have any idea what a terrific resource the Net is.

Anyway, I've seen it happen too many times, where people say "just having this motor back like it was is enough for me"; then they do that, maybe do a great job of it even, and discover that for very little more money, they coukd have had ALOT MORE than they started out with. But then it's too late. I guess I kind of see that coming, having seen it so many times before; I don't want to see people gp through that.

This hobby usually boils down to fun per $$$. That's my specialty. Using dollars wisely so that you get the most fun with the fewest regrets later.

 

But would my 305 tbi & intake bolt up to the 350? This is something that I have been thinking about, but don't know about my tbi.
And no, I want to keep it so please don't say anything about carbs.

 

Yes they will bolt up. Everything from your 305 will transfer over to your 350. You may want to consider better parts though before you start putting stuff onto your 350. The 305 TBI pretty much had the worst possible combination of assembled parts from GM.

 

If you want to keep TBI, then get yourself a healthy 350 shortblock. Find some good heads for it. The best junkyard heads to use would be 416, 601, 081 for 305 heads (they work pretty well on a street 350) but only if your 350 has dished pistons, otherwise the compression can get too high. The BEST heads you'll find at a junkyard for a 350 is probably 083. They are the 350 TPI heads.

Of course, whatever heads are on the 350 (if they arent TBI heads) are likely better than whats on your 305 right now anyway, so you could even re-use those.

 

so i have an LG4...an if i go to a junk yard a buy a 350 head for 50 bucks....what else would i need to do...i'm such a newbie....help me out

 

DON'T use 350 heads on a 305.... it will drop your CR to about 5:1. You got it the wrong way around, you can use 305 heads on a 350 and make good power and compression.

If you have an LG4, then you have either 416 or 081 heads (depending on year) and those are good heads to keep for either your 305 or for a 350. If you do buy a 350 at the junkyard, you are probably better off to throw away the heads it comes with and put your 305 heads on it.

 

i have a 305 and i want to swap in a 350, but im just worried about getting it started and working, there is such much to deal with when you swap in a new motor. i live in california and i need to pass smog, but i don't want to buy all the efi stuff.