Well this will be my first build and im really needing advice.  I am well advised that a 305 is for sissy's but, that is what i have for the moment, and am not planning on keeping it for long. The 350 will be next.  But, i need some guidence on the proper upgrades that will make my 305 a little more radical than a stock 350, and i know it can happen because a buddy had a 305 that eat up a four bolt main with ease.  needless to say the 350 was new, but had the basic parts with a quadrajunk. So far the plan is double hump or 350 heads with a decent cam, i hear lunati makes a good one but, the question im asking is how aggresive can i get with the cam without the hassle changing the piston, rings, or anything of the sort? dont mind dumping a little money in the heads but what are my options guys? Also is msd ignitions cracked up to what i hear??  Any help with my issue would be greatly appreciated.  

Well, you aren't going to find any professionals so you will have to settle with me...

First off, especially if you plan on building a 350 later there isn't little to no purpose in putting money into a 305 now. Everyone will say that you can switch over the parts to the 350 but that's easier said then done when you don't want a half-assembled boat anchor in your backyard and it takes money to build an engine regardless of when or how you find the parts.

A 305 ruining the mains says nothing about the amount of power being made by the engine.

A worn out engine may need rings regardless of what size of cam the engine has.

Leaving the stock compression ratio does limit your cam choice but the gearing and rest of the combination will probably limit your choice to a greater extent.

Any aftermarket camshaft manufacturer will make a "decent" cam for you.  

hey GIBTg, i really appreciate the input, but your comments had nothing to do with my questions about the cam situation. Actually the motor is in decent shape but i had a problem with city pricks stealling the intake, carb, distributer,and holley fuel pump.  So i figure, since it was in that shape i mise well attempt to do a little something for the getty up and go.  And if i do go with 350 parts i beleive i would leave everything on it when i seel it.  Bump the compression on the heads and i should be able to put and aggresive cam in there right?  By the way i have an performer edelbrock intake and a 650 carb. Too much  carb?  Was hoping with the right cam and heads maybe the carb would be suitable.  

I think the first thing you should do is spend at least 6 months reading an engine building book cover to cover.  

hey im just needing a little advice for the best results from peoplel who know what might help.  If you have nothing to offer or any useful advice, just be a smartmouth to someone else.  Besides that, this is what the forum is for isnt it?, dummies like me that just need a little advise from fellas that know what their doing?  

You need more than a little advise if you think that because if an engine has four bolt main bearing caps that it should be able to smoke an engine with two bolt caps! Putting an "aggressive cam" to an engine takes a lot more prep than screwing around with a set of heads. Have you thought of intended RPM range, gearing, exhaust system, just to name a few.  

"Leave everything together when I seel it"
"Bump the compression on the heads"
"Put an aggressive cam in there"

These statements don't make any sense at all. I can't really determine what you mean or what you need help with.

If you need help picking a cam there are many things to consider, like "JW454" said, you can't just ask what "aggressive" cam can I throw in for some "getty up and go."  

I'd call Comp Cams, they have a nice selection of 305 specific cams that'll wake your motor up and make it more fun to drive as is. I'd also recommend a valvespring upgrade, and a double roller timing chain.  

COMP X-treme energy

part# 12-230-2   grind: XE250H

Not "aggressive"  but very strong low end torque.
Very quick opening lobe ramps that maximize flow without having too high a duration.  Smooth idle, great throttle response. Will work fine with stock converter will not affect vacuum for accessories.

Also keep the 305 heads.  You are not going to need the bigger valves of a "350 head" and will only lose compression due to larger combustion chambers, in most instances.  

do you really want to dump several hundred dollars into an engine that will have a hard time finding 200hp?

These guys ar trying to help you in ALL of the advise they have given, I think they are just trying to save you the dissapointment of your 305 after it is all said and done.

yes, the 305 can be a fairly "HOT" engine...but not until a lot of money, machine work and time has been put in them. We have a 305 sprint car class and they have surprised me!

be open minded....and listen to them.  

You can certainly change the cam in your engine, and if you want you can put in a big nasty cam that will make your 305 sound like a race car.  Unfortunately it will also turn your car into a turd.  I understand your desire to find multi tasker parts, that will work on the 305 and transfer over to the 350.  It is a good idea.  Do the double hump heads your thinking of have any accessory holes in them?  What 350 heads are you thinking of putting on your 305?  Do you have stock rear gears?  Is this thing going to be used mostly on the street?  If you want a lopey cam that won't require you to build the engine around it go to comps website and download their camquest software.  It's free and it will help you decide what you need to do.  Also take the time to call any of the 800 tech lines out there and discuss with them your project.  

This is for 55guy, shootnrats, and smokeshow. Sounds like you guys new somewhat what i was trying to say even with the misspelling, and it also proves, you certain guys have actually read all the items above and i appreciate the advice that has been given and will look into everything that has been mentioned.  Also i will definetly look that part number 283 john gave me, maybe now that i have a somewhat direction to look at maybe now i can get some where.  For the guys that actually gave helpfull advice, ill keep you fellas aware of whats goin on.  

GIBTG and JW454, i somewhat understand what you guys were trying to say but, man!!  Did either of you actually read anything on the posts???  Ya ya ya i misspelled a few words on em, but where in heck did ruining the maines come from?? Its not that hard to read, " a 305 smoked a 350 that was a four bolt main, with stock parts, i was just simply saying that, even though its funny, you can make a 305 outrun a stock 350. Or is it that hard to figure out that seel might have been misspelled and i maybe meant sell???  Gee i wonder what part of the motor would bump the compression ratio?? hmmmm. Tough one huh? Sorry for the sarcassim but damn!! Read befor you type, its easy, 1,2,3.  

How can you ruin a state with either a 305 or a 350?

Sorry for the sarcassim, but I just prefer straightforward English.  

Pardon me, this just came to mind.