Thinking about rebuilding the top of my motor, since the bottom end will never die. Going with a mild clean up on the stock heads, intake, and tb. I will probably chose a LT1 cam and EBL.

1) Should I gasket match the intake and heads to a large port size?
2) Which type of valve seals do I want, so that I don't burn them up and get white smoke on start up?
3) Should I use a thinner head gasket to bump up compression?

 

I hate to have to say this, but you're wasting your time. Just build a 350. Even a used one will be better than what you have. The 305 doesn't have very much potential.

 

If his bottom end is good he can still make a 300hp 305 TBI. Both set-ups will require larger injectors and tuning but he may not want the cost of the 350 shortblock. Both Dewey and Fast355 would beg to differ that a 305 is worthless. FWIW.

1. The stock port size is fine. The heads need work in the runners, bowls and some tweaking on the swirl ramp. I would use a stock intake gasket and port match to that (if needed).

2. Unless you have had the valve guides cut I would run stock replacement valve seals. Your intake valve seals should be positive and you should only have a rubber oring on the exhaust. You can run positive seals on both intake and exhaust but with an LT1 cam you will need to measure for clearance. Going past .480" lift on stock valve guides will not allow you to run positve valve seals.

3. Many people run a .015 head gasket. A little bump in compression is always good but I would refer to Fast355 and Dewey316 for their opinions (to my knowledge they run this size).

 

I didn't say a 305 is worthless, in fact, I built one a few years ago that had really good torque and about 250 HP.

Thinner head gaskets are good to tighten the quench distance. Stock engines typically have quite a bit of deck clearance and running a .015" head gasket is a good way to improve quench which lessons detonation potential and increases compression. My only suggestion to someone using a head gasket that is that thin is to ensure that your block and heads are straight enough so tht a .015" head gasket will seal. If you have quite a bit of warpage, you might be better off just running a composite type head gasket to ensure you don't end up with a head gasket leak.

Stock 305 heads are really rough, a cam with increased lift without too much duration will help big time. Liek thea above poster suggested, a clean up of the rough ports and bowls will probably net a significant improvement.

I won't call a 305 worthless, but just don't go too far. I invested way too much money in my 305 back in the day and I would have been better off just buying a 350, if for nothing else, because the heads flow better over 4000 RPM and that gives a pretty serious improvement in horsepower.

 

1) Gasket matching doesn't increase flow much. It's only relevant for very high-reving motors (which a hydraulic roller lifter motor like yours will never be). If you want to do it, and if you're careful, you probably won't do any harm ...but you won't get much (if any) gains out of it.

3) That cam allows you to bump the compression up with your stock heads. Even with the thinnest gasket you could get you'd still be under 9.7:1 CR and be safe with an LT1 cam.

With headers and exhaust, ultimate TBI mods and injectors and fuel pump to match, you'd probably get an extra 65 hp over your stock L03 ...somewhere around 275 fwhp. Don't forget the chip tuning or you're wasting your time. All in all, it's well worth doing.

And, by the way, get used to the "you should just get a 350" crap - it's the standard response you get from many people around here if you ask a question about any small-block other than a 350. In any case, there are a few 350 hp 305 owners on here (and yes, we are all aware that there are 350s that make more than that for just as cheap or cheaper).

 

I know that the 350 would net more power, but the 305 is still alive. I'm trying to do this as budget as possible. I was running a modified ecm for a whlie but I'm going to convert to EBL when I get some cash.

I have some cheap flowtech headers and y-pipe going into 3" pipe into SLP dual/ dual exhaust. I have already upgraded to a tpi fuel pump. With adjustable fuel pressure can I get away with 350 injectors (55 lbs)?

I've read tbi posts for the past two years, I think its becoming the time to start acting.

 

At 20 lbs/sq inch the 55 lb injectors can flow about 68 lb/hr. At 0.85 volumetric efficiency that makes about 275 hp ...so you should be fine.

 

hey,
my L03 pretty much flies, its fairly quick. its completely stock and fairly pleased with it. it could use a slight power boost but nothing drastic. it get excellent gas millage 24+ MPG, doesnt burn any oil. its also a very reliable engine, the fact that it is slightly underpowered means you cant really kill it by beating on too easily. if i could make what the stock LB9 gets, that should be easily accomplished, i will be very happy. you're not going to get anywhere near 24+MPG overall combined highway/city with a 1st gen 350(pre LT1). a 305 will deliver great millage which keeps money in my pocket. how fast do you really need to go? where i live state speed limit is 65 mph. so spend your money wisely rebuild the L03 and spend a few hundred on performance upgrades im not saying that a 350 is a bad motor, its a great motor but with gas prices up around $3/gal you have to put fuel economy into consideration. eventually i would like to improve exuast, get a better air cleaner assembly, and get a hypertech performance chip. if i ever got a reman L03 i would make sure i used better heads and cam. you can also get a high performance TBI unit avaible through holley on summitracing.com, and an improved flow intake.

 

ad356,

I agree with everything that you said. I'm building a 350 at the moment, but I have a lot of respect for the 305 guys ...actually, I've got a big itch to put together a 305 myself (perhaps a 305 bored and stroked out to 334).

The L03 is an extremely durable motor. I have a friend who has a 1988 L03 with over 400,000 miles on it. It pulls a heavy van around and has never been properly cared for (no regular maintenance, oil changes, etc.).

The amount of 305 bashing on these internet discussion boards is unreal ...you'll get everything from "the bore is too small for the stroke", "there's too much valve shrouding" to "the 305 is a worthless turd".

Actually, the stroke to bore ratio of the 305 is the same as for a 383 and a LS1 (346 CID). The stock 1.84" 305 intake valves are larger proportionally than 1.94" valves on a 350, and 1.94" intake valves on a 305 are proportionately larger than 2.02" valves on a 350 or 383, and also proportionately larger than 2.00" valves on the LS1. The 1.50" exhaust valves on a 305 are larger proportionally than 1.6" valves on a 350 or 383, and even larger than 1.55" exhaust valves on a LS1. And any shrouding problems that come up if bigger valves are installed (like 1.94" valves) then they can be relatively easily fixed.

Also, for a street car, there really is no need for a motor with a lower stroke to bore ratio (which is part of the reason why GM replaced the 350 with such a motor - the LS1). Street engines generally should make their best power in the idle to 5500 rpm range and a stroke to bore ratio of 0.93 (the 305, 383 and LS1) is perfect for making torque in this range. In addition, the hydraulic roller lifters in these cars limit their revving potential to a little over 6000 rpm anyway. So, the L03 is actually ideal, internally, for making power in this range.

Of course, I'm not debating that the 350 is a bigger and more powerful motor, but nothing says that the 305 isn't a great base for a strong street machine.

 

I am glad someone finally agrees with me. Now that mw66nova has run middle 12s with a NA 305 people may change their minds. I made great power with my 305 and could get 23 MPG on the highway in a 5,500# aerodynamic brick. My 350 is touching 20 MPG, but it doesn't achieve it nearly as easily.

You also have to remember that the 305 has lighter pistons, light crankshaft counter weights, and less overall rotating mass meaning it will turn more RPM with less stress and be snappier.

I recently put a pair of worked over ZZ4 heads onto my old 312 in place of the cracked heads that were on it. With the Crane roller cam that was in it, aluminum LG4 intake, worked over Q-Jet, 1 7/8 x 3.5" headers, and a recurved HEI, it made 410 FWHP @ 6,500 and 385 ft/lbs @ 4,750 with over 300 ft/lbs from 2,400-6,800. With the idle mixture/speed/timing tweaked it was capable of 15 in/hg of vacuum (very TBI friendly to tune) and it ran dead smooth. I was thinking it would make around 390 HP, the dyno operators laughed with the way it idled and said I would be lucky to get 300. They ate their words soon after. It is not in a vehicle yet, but I am thinking of replacing the TBI 4.3 in my 1988 GMC Jimmy with it. If RBob would only let me Beta test dual 2 bbl TBIs or a 4bbl TBI with his modified EBL ECM (Hint RBob, are you listening).

 

I also think that, historically, the 305's reputation has suffered because it was introduced during the mid-1970s as a low-output motor ...but all of the small blocks of that era were low-output motors. And then, when GM finally developed suitable technology to keep emissions in check, the 305 got replaced by the 350 in all the higher output vehicles. So, GM never really made a truly good performing 305 from the factory - that did a lot to hurt the 305's credibility as a performance engine.

Also, many people have tended to throw 350 parts at the 305 and expect it to repsond the same. Of course, it doesn't, so the 305 gets tagged as a "lame duck". Really, all of Chev's factory high-output small blocks, and also the one's that people have modified the most, have a 4.00" bore (302, 327, 350). So, the nuances of getting performance from a 3.736" bore is much less known and considered by many as non-existent. So, the 305 gets hit with all kinds of mocked-up reasons as to why it can't perform - "I wasted lots of money on a 305 and it was a turd, so I scrapped it and got a 350." Of course, when we see people with 350+ hp 305s it becomes obvious that the 305 can perform and if somebody spent money on a 305 and couldn't get anything from it, then, obviously, they were doing something wrong.

Of course, we all know "there's no replacement for displacement", but in the low-to-mid rpm ranges (and, obviously, even over 6000) the 305 can, cube-for-cube, holds it's own with any V-8 motor on the street. That's not to say that a bigger motor isn't better ...but that doesn't discount the 305's ability to perform very well in it own CID class.

 

Exactly, so swaping to a 350, or simply selecting a 350 block when rebuild time comes can be worth more than 50 HP. You just can't do that with very many other parts. It's much cheaper to rebuild a 350 as well. I wouldn't necessarily swap a perfectly running 305 for a 350, but when upgrading the 305 I would make sure all my speed parts would work well with the 350 as well.

So yeah performance can be had from a 305, just don't kid yourself into thinking it would be a better choice over a 350 unless that extra couple MPG is worth it to you.

 

With the inefficiency of 305 heads, I'd even question that.

 

With a few exceptions, 305 heads are no more "inefficient" than any other stock small block heads ...and any "inefficiency" can be easily remedied with a DIY port and polish job. The number of convenient head options on the market for 305s is certainly limited compared to 4.000" bore motors, but options are there.

 

Factory 305 heads are some of the worst flowing SBC smog heads ever produced. You can decide to spend your money on them if you like, but I wouldn't spend a dime.

 

You can get them for cheap as dirt and port them out yourself to flow as well as some Vortecs. The non-swirl versions can flow 220 on the intake and 160 on the exhaust with DIY home porting and polishing. That's better than stock LT1 heads, and plenty for what most 305s will be breathing. The swirls will be weaker on the intake but better on the exhaust. There are several members on here making well over 300 hp with factory 305 heads.

 

I don't necessarily agree with that statement. The 601, 416, 081, and Vortec 305 heads will outflow many of the 1.94/1.50 heads used on 60s era 327/350 engines IN STOCK form!

205-210 intake and 130-135 on the exhaust on the 601s in particular. They have the same chamber shape as a 492 head but with 52-53 CC chambers.
-

 

Fast355,

Do you think it's possible for me to port the hell out of my 601s and get the exhaust side up in the 180 range? I was crunching some numbers and playing with some simulations (just got some new software) and my set-up doesn't seem to gain anything past 240 on the intake and 180 on the exhaust side, so going to FlowTechs would be an awful expensive jump for a few cfm.

I think getting 240 on the intake shouldn't be a problem. I know 160 on the exhaust is quite do-able (I probably have that now), but I'm hoping with some under-sized stems and back-cuts on the valves I might be able to get 180.

If I can get the 180 I'll be able to get the motor back together and in the car this summer ...or I might take the money that I won't spend on heads and stroke it out to 334. Expensive game to play with a 305, I know, but I'm concurrently building a 350 and would love to see what I can get from the 305.

 

I spent approximately 6 hours on my set when I did them. Most of my work went into the exhaust side with only like 10-15 minutes spent on each intake port. They were at 224/160. IMO, 180 is possible on these heads. It ran great with a Comp Xtreme energy 274.

 

You do realize that absolutly no one will know what block your running right? Externally there are no clues other than some grimmy casting numbers on the back of the block. If you want to drop more money on building a 334 than what it would take to build a 383 more power to ya.

I gave up a long time ago trying to be different, I found out it's much cheaper and rewarding to do what makes me happy personally. Hence the reason I auto-x a land yaht like my monte. It'll never win anything, but I enjoy it and it's fun for me. If it's fun knowing you made power with a 305, great more power to ya, but I know I would have more fun with the extra 50 HP.

 

I have to agree that if it's simply bang-for-the-buck, then you'd be a fool not to build a 383 for the same (or less) money.

But for me, there's simply something about keeping the original block that came in the car ...especially when it can be made to perform. With the right thought and investment I don't see why a 334 can't make 375 hp in a very street-friendly manner. Of course, the same amount of money spent on a 383 would probably make 450 hp (in the same rpm range).

But, on the street, 375 hp is a VERY respectable, and fast machine ...and, in the case of a 334, it comes in a very unique package that still retains it's matching numbers. That might not be important now, but in 10 years or more, when these cars start getting rarer, a matching numbers car (305 or not) will probably be worth more than one with 75 more hp. It is to me right now.

So, if performance alone is the issue then nobody can argue that building a 334 is a very cost-ineffective way of doing things ...but in the context of the total car and it's intended purpose as a street machine, then I think a 334 has definite merit. I know it's not a popular viewpoint, but it's where I'm coming from. I hate ditching any original small block when it has potential ...and down the road, it might not be such a bad investment. Again, it all comes down to what you have in mind for your car.

Having said that, I wish mine came from the factory with a 427.

 

How is it numbers matching if you have changed the crankshaft? You do realize that there are numbers on a crankshaft, right?

 

The block, heads, intake manifold, exhaust manifolds, alternator, water pump and carburetor (or FI) are the major engine components that are used to determine "matching numbers". Of course, strickly speaking, changing the crank does "ruin" the true authenticity of a car, but for practical purposes, it doesn't "ruin" matching numbers ...changing the heads, headers, intake, etc. does that ...but these are bolt-ons that can easily be replaced with matching numbers components if necessary, and are generally not taken as serious infractions to the "matching numbers" designation as changing the block.

 

Don't let anybody tell you the 305 isn't worth building. Mine is making "about" 360 horses and 360 ft-lbs. Enough to make the high 12's (when I can get the traction, that is). Of course, I built up just about every part of it that's buildable. And to get that much out of it, I pretty much ruined it's low-speed manners.But I still get 24 mpg out of it, as long as I'm running over 70 mph. Below that, it spits and backfires. Too much cam.Anyway, it CAN be done. You can accomplish most anything you put your mind to, if you do your homework and do the work right.My next motor, a small-block 400, is an attempt to keep the 12's, get the street manners back, AND keep the gas mileage. That's another one that "they" say can't be done.You never really know for sure until you try it yourself.

 

With the right head work, headers, exhaust, intake, ROLLER CAM, and tuning you can get 370-400 FWHP out of a street-able 305. I was still getting 18 MPG in a 5,500 lbs brick and making 301 RWHP through open cut-outs.

 

Just because you can make power with a 305 doesn't mean it's "worth" building. "Worth" to me has more to do with HP per dollar spent. It's "worth" building on a 305 up untill it needs the bottom end freshened, the it's "worth" going to a 350.

For the last time NO ONE IS SAYING YOU CAN"T MAKE POWER WITH A 305, you can. You can just make more power with a 350 for less money.

 

This is the argument I have been having with myself for weeks. Im starting to plan an engine build. Im shooting for a N/A engine rating of about 400+ hp. Then Im going to spray it a little(100-150, maybe not so little). My overall goal with my car, is 11s, and low 11s if I can. Everyone, and I mean everyone, from the 4th gen owners, and the mustang guys HATE the L03. I get more hate from Ls1 owners over my engine than the 5.0 mustang guys. It makes me want to build a little 305, just to shut them up. Granted, the 350 would make more, for less, but anyone can call and order a 400 hp 350, from an engine builder. So, Im stuck arguing with myself. Either build a cheap, easy 350(like everyone else), or do a little more work, spend a little more money, and keep the 305. Noone will know, but me, but its a pride thing. Im just tired of all the "305s are crap, they are worthless" BS. Its not an Ls1, so its junk. Its a smog motor built in he 80s. But its still a V8.

 

I hate to have to say this to you, but that's really pushing the limits of what's practical (and possible) in a hydraulic roller 305. If you pick a cam with fast ramp rates (which takes advantage of the hydraulic roller lifters) then you'll be limited to about 6000 rpm before valve float occurs. You can install a rev-kit which will allow a few more hundred rpms, but 6500 (or so) is still pushing the danger zone for most hr cams. I'm not saying there can't be exceptions, but as a practical limit, 6000 rpm is about the most I'd try to push the hr 305 (or 350, or Ford's 302).

At a practical 5500 rpm, your 305 is going to be pushed to make much more than 350 hp without juice or a supercharger. An equally prepared 350 will make about 400 hp at around 5500 rpm.

LS1s and 302s are also limited to the idle-to-6000 rpm range. The Ford 302 is a short-stroke, large-bore combination, which means it's more ideally suited for higher-rpm operation - which it can never perform safely because of its lifter design (at least since 1985). In the idle-to-6000 rpm range the 302 has no performance advantage over the 305. Of course, the LS1 does.

People who hate the 305 are typically people who either have a bigger motor or a 302. People with bigger motors often bash 305 owners simply because they're "bullies" and have insecurity problems. 302 owners typically bash the 305 because they desperately enjoy pretending that they have a better motor, and they use out-dated and irrelevant "facts" to back it up.

 

Ahh, the arguement that refuses to rest. I truly believe that people make the same mistake with camshaft selection, as they do when determining block selection. Most people buy a camshaft, without thoroughly researching it, then try to build the rest of the valvetrain, trying to accomodate their selection....

Same goes for the anemic "305". People decide to build it, then throw whatever parts at it that they can... in the attempt to do battle against it's older brother, the mighty "350". As far as I'm concerned, that's the wrong approach.

Symmetry (not just in the valvetrain) is very key when deciding which engine to go with. Suspension, gearing... and vehicle weight, are huge issues to consider. It's not the "305" that refuses to run 11's naturally aspirated, it's the situation that it's in, which holds it back from doing so.

I remember seeing some crazy swaps with the LB9 engines, finding themselves worked over the right way, then being shoe-horned into a very lightweight, RWD, Import. These guys seem to have no trouble at all running the numbers that you're all after (10's & 11s), because they have a much more clearer understanding in reference to the principle of power to weight.

 

I would be willing to accept 325-350 hp, to keep the L03. Then spray it with a 100 shot. That would still net me 12 or 11s, done right. And I would drop my overall goal to low 12s, just to keep the L03, and hush the naysayers. Im sure the information is here, on how to accomplish a good 350 hp L03, but its a bit scattered, and the best example I could find, was carburated. At any rate, Ill keep digging, but its rather hard to sort thru all the info, and skip all the irrelevant stuff, especially when you dont know that much about engines really. Dont get me wrong, I can find my way around, and can do quite a bit, but Ive never built a V8. Ill buy my rockers in a few days, and start saving for a tuner. Maybe by the time I get the tune down to an average tune, Ill feel more confident about building an engine. I just hate the idea of having to jump on the "throw away the 305" bandwagon, just because of the lack of interest in the aftermarket.

 

The aftermaret is already there, you just have to know how to piece the project together. Regardless of engine size, as we all know, all power comes from the head and cam combination. Don't simply shoot for a cam that will net you the best "peak" numbers, focus on making power under the curve as well. The rest is all in the suspension, gearing (stall, for the auto's) and weight for you're F-Body....

 

Thanks for the (unusual) words of comfort. Most are just like, "junk it".

I would even pay for a custom cam, if itll work better. And even bore/stroke the motor. I wanted to build the 305 at first, but then everyone trashed on it, so I started second guessing it. I know a bunch of you guys run fast with 305s. And Ill get the suspension worked out, but Im wanting to improve the engine first. Im tired of 16s. The car is looking to good to run with civics. I guess I need to break out the desk top dyno, and start running numbers.

 

These are the very same people that will recommend over-camming an engine. If you want to build the 305, I say go for it. Mind you, you will always make more power with more cubes (more cubes = more torque), that's a fact... but again, power to weight!

Yes, without a doubt, a custom cam will work better. Never go with a "commercial" cam, even from the top names. Have someone grind you a cam that will cater to you're own specific needs, and the types of "lobes" being utilized today are very key. Contact the people at Thunder Racing, and they'll be glad to help you out on you're selection!

You'll get there, don't worry. First order of business is deciding which system you're going to go with, and stay with. Will you stay with the TBI, will you rip it off and throw on a Carb, or have you been considering TPI. This alone will help you determine which valvetrain to be contemplating.

I myself always wanted to see a 305 being built up with the "baby" LT1 intake. This, accompanied with the right heads, and custom camshaft (remember, lobe selection is very key), and proper tuning ability.... and she'll freaking scream!

 

Im set on TBI. Period. No carb, or TPI. Even if I go with a bigger engine, itll be TBI.

Cams are always a big point of mystery, as are heads(to me anyway). I can only copy what someone else has done. Im not an engineer, and Im on a smaller budget than alot of you guys. But, I guess thats something we all face. Im just anxious to go fast. And I hate to keep asking the same questions you guys have answered a hundred times. I guess when I get the money to start spending, Ill start asking around.

 

Learning to tune is essential then...

Use the time that you spend saving for the necessary valvetrain to understand how everything works. Don't use the term "small budget" as an excuse to buy the first commercial cam that you find on a discount. If you want to make power, you need to spend the money where it counts!

Camshafts are a balancing act. Heads need to flow, as well as help dictate compression levels... in which too, are very key when determining camshat selection (referring to dynamic compression).

Are you kidding? Ask away, that's why we're all here. This is a wonderful hobby, and sharing is the most rewarding part of it!

 

Few more questions

1) Should I use the lifters from the lt1 cam, if I can buy them together? Or just use stock?
2) Reusing stock pushrods and rockers is fine and keeps me on budget, correct?
3) The head bolts need to be replaced, correct?
4) Are there online pictures of the rough spots of the heads that need cleaned up?
5) What places on the intake manifold should I clean up?

 

if it makes a diffrence, mine is making ~415fwhp based on the ET and weight. it's got GREAT street manners and i drive it everyday i can. i love the car. i've managed 16mpg in town and 22 on the highway, and that's with a 650 cfm holley doubler pumper.

 

I believe that HP output, mine dyno'd very similarly a while back. My main difference was the LG4 intake, Q-Jet, and smaller cam (it is smaller, but it is also a roller which makes a big difference in area under the curve).

You've got to love long duration EFI cams with virtually no overlap or negative overlap.

Comp Xtreme EFI retrofit roller P# 280XFI-HR13
Advertised -280*/288* Duration
.050--------230*/236* Duration
Lift(1.6:1)--.576"/.570"
LSA---------113*
ICL---------108*

Here is the DD2000 graph, the real curve is very similar (need to dig it out so I can graph the chart in Excel and post it.

Cam sound on my engine "test stand", through a pair of Flowmaster 50 Series Delta Flows and headers.

 

Well, I couldn't get the sound loaded on the Host, so I had to make it into a short movie. This is version # 2 of the same engine warming up on my test Dyno in either TBI or TPI form (can't remember which). I think this was on the dyno in TBI form, but my Vortec PCM run TPI setup spent some time on this engine the same day as well.

YouTube - 400 FWHP TBI 312

 

hehe, sounds kinda like mine but i think mine idles lower. what does that one idle at? mines at a solid 750-800rpms.

 

Probably around 950 or so in that clip. The engine was stone cold.

I will look up my idle table, the CTS was around dyno cell temp, probably about 20*C.

Fully warmed up it idles around 16-17 in/hg of vacuum @ 750 RPM in Park/Neutral. 60 MAP is about 12.3 in/hg of vacuum, but it was also burn your eyes rich as it was warming up due to the fact that I used a .BIN for my L82 cammed 305 with ported 081s on it. The aluminum heads like alot more timing, especially at idle. After some tuning, it corrected the problem.

BTW, that little RPM spike after coming down from the steady 2,000ish RPM was all the IAC and further shows how lacking my tune was, even on the 68th burn.

 

415 hp @ 6500 rpm in a "streetable" 305 ...that's 1.36 hp per cubic inch ...a very respectable accomplishment with a motor that people love to hate so much.

I'm building two motors at the moment ...a 350 and a 305 (L03). I'm planning on about 350 hp with the 305. I'm estimating that I had a little over 275 hp from it last year. This year (probably next year before everything is tuned and completed) I'm re-working the 601 heads again (1.94" and 1.6" ferrea valves and serious porting), going with a higher compression ratio (flat top hypereutectic pistons) and bigger headers (1 3/4"). It might get a steel crank and forged rods too, but that's not critical ...and it will remain TBI.

Gladstoneiroc....

1) You can use your stock roller lifters - they're fine.
2) You can re-use your stock rockers and pushrods. If you want extra insurance you can get a set of cheap Comp Cams hardened pushrods ($35 I think), but most people are fine with an LT1 cam and stock pushrods.
3) You should get new head bolts. Old bolts stretch and fatigue. It's always a good idea to replace head bolts when you remove the heads (unless you put them on new very recently).
4) There are many online pictures of home porting jobs. Check the Standard Abrasives website and do a search on this forum.
5) Any places that have rough edges and obvious areas that would cause turbulance and flow obstruction. On a motor making power below 6000 RPM you don't need to worry about doing a lot of work to the intake runners. Just look and feel with your finger. Remember, you don't want to enlarge the cross sectional area of the runners, just smooth out the imperfections.

 

My old engine with the milder crane roller cam, ported 081s, and less stall ran a 15.1 @ 95 mph consistantly in my 5,300# G20. I am currently running this engine through a simulator that I have found pretty accurate.

Here is the results of the simulation, I think that it would go quicker given the fact that the simulation assumes WOT from the second it starts. It predicts a 60' of 2.48s, I have achieved a 1.98 fairly consistantly with my 350, and 2.18 with the old 305. It just models tons of tire spin (through the mid-range of 2nd with P295/50/R17s!)

0060'----2.48s
0330'----6.41s @ 58.93 mph
0660'----9.60s @ 80.15 mph
1320'----14.61 @ 98.77 mph
0-60-----6.3s
0-100----15.2s
5-60-----6.1s
20-80----8.0s
40-70----4.5s
Top------144 MPH
City------11.9 MPG
Highway--16.0 MPG
Combined-13.4 MPG

You don't even want to know what it has predicted for my 4,200 lbs GMC Jimmy.

Try a 13.4 @ 105.4! I am relisticly hoping to see a low 14 to high 13 in it.

Given the right lower-end, right valvetrain, and enough driver, this engine would want a 3,000 stall and a 7,000 rpm WOT shift-point. I pulled this one up to 6,800 on the dyno, atleast a dozen pulls. The CHIP was tuned pretty well for WOT from 1,500-5,500 or so, then it went way rich. I tweaked the warm idle pretty well too. It still needs lots of tuning when it goes into the vehicle though, mostly for part-throttle driveability as WOT power is awesome.

 

why do people still build gas guzzler 350's? i met someone the other day at napa who had a 1992 camaro rs 305 very similar to my car. he dumped that poor innocent 305 for a guzzler 350. he wasnt even driving the car it was sitting at home in his driveway. he was driving a crapp scion(i dont care for them at all). my question for him was what was the point of replacing that 305 with a 350(it was a strong 305, not worn out anyway). he said it didnt have enough power. well i bet that scoin doesnt have enough power either. in fact i bet that 305 runs circles around that scion with very little work and maintaining fuel millage. that 305 may not get quite as much fuel millage as the scion but i bet its close. what was the point of getting a 350 that he couldnt afford to drive every day? i will drive my camaro every summer day and i will rebuild it forever. i bought my car do drive not a driveway queen. i respected him for owning a third gen but thought he was a fool and contradiction for driving that factory bling jap car. im an american and i am very proud that we built great fantasic products like the third gen. the japanise dont know how to build a car with that kind of soul.
by they way it was 305 bashing day at napa, even the parts counter guy said he would never drive anything powered by a 305. i think the 305 is a fantasic engine and i have seen many run for many many many miles.

 

LOL, I used to work for Autozone. If I couldn't get something there, I was off to Orielly. It was usually something minor, window motor, blower motor, parts for other projects, etc. The guys there were 305 haters. When I was a little younger, I'd leave a nasty patch of rubber in their parking lot when they laughed at my 305.

YouTube - Van Burnout

 

I'm not an American, but I'm still proud of you for the small block.

I've have a friend whose run into this several times. He called a machine shop to ask about balancing a rotating assembly. He told the guy it was a 305 and the first thing the guy said was, "Ooooooo ...not a good idea ...not a good motor." Then he went into a spiel explaining why the Ford 302 was an excellent motor, but the 305 is one of the worst motors ever built ...my friend was quite offended because the guy spoke to him as if he was a little child that didn't know anything about cars.

Another time I called a machine shop myself and asked about getting the seats in my heads cut for larger valves. I was referring to 350 heads at the time, but out of curiousity I also asked about getting larger valve seats cut for 305 heads. He said, "Ahhhhhh ...I wouldn't bother doing any work on a 305. That's not a good high-performance motor." He explained to me about how a lot of young kids (implying that's what I am) get ripped off because they buy Camaros with 305s and they don't know the difference.

I find it ironic because these guys usually know next to nothing about actual motor design and dynamics, yet they explain to me why I should buy a 350 4-barrel (if they don't know that I already have a 350 - if they do know it they tell me that fuel injection is crap and I should get a carb). They usually say some typical slander that the 305 has a bad stroke:bore ratio or the valves are shrouded or the rods are too short for such a small bore. Of course, it's all pure nonsense. Fact is, most of these guys have never attempted to mod a 305, and the ones that have didn't know enough about engine building to be successful.

The simple fact is: If there was a problem with the 305's design/construction, then it would be evidenced by a drop in volumetric efficiency as the rpm climb. Fast355 and mm66nova (plus others) both have 305 motors producing volumetric efficiencies of 0.87 or greater at above 6000 rpm. My 305 was making close to 1 hp per cube at 5000 rpm before I took it out ...later this year (hopefully) it will be making 350 hp at 5500 rpm - that's a volumetric efficiency of about 0.88. A VE above 0.87 at over 5500 rpm indicates no valve shrouding or problems of any other sort. 305 bashing is based on bull****. The only logical argument against the 305 is that it is simply too small ...but much bigger than the 4 and 6 cylinders that people sink their money into everyday.

 

well...to be honest, people build "gas guzzlin'" 350's cause they make much more efficient power, and most of those guys just want to go fast instead of doing all the research on putting together a well thought out 305. while i'm not getting the MPG you guys are with my carb, i think that 16/22 is pretty decent with my 305 HOWEVER, while the 350 that i had in the car could make the gas dissappear much quicker than the 305 when laid on, the 350 still managed 15/21 for gas mileage and was .4 quicker than my best pass ever with the 305 and i had some serious traction issues with an open diff and no lca relocation brackets on my spare rearend that i was using since i grenaded the good rearend. on the fastest pass with the 305, i had the suspension totally squared around and the posi back in her. i wished i could go to a taller rear gear now, but i don't know how it's gonna act when i get my power adder on it...so i'm gonna mess with tire size instead.

 

Which is exactly why I put a 350 into my G20. I needed torque down low, lots of it. The 305 was about 60 ft/lbs short in that area. My 350 is loaded with torque, even though it is slower. I just don't have to rev the 350 up to 5,000+ getting on the highway.

 

If your running a carburetor, sure, 350's can be considered gas guzzler's. But with the advent of fuel injection, this has since been proven to no longer be the case. This guy that you met, who swapped to the 350, maybe he's looking for more power under the curve, as opposed to peak. If this is the case, then I would agree with his swap. There is no substitute for cubic inches when it comes to making more low and mid range torque....

 

i would consider an LT1 swap in my car but only if i could find one resonably. good luck on that. the LT1 will get similar gas millage as my L03, if not better. it is truely an amazing engine and its too bad that it didnt come around until the 4th gen. it would be awesome to have one in a third gen stock.