Dont waste your money get a 350 or 400.

 

i'd suggest opening up the exhaust if u havent done so yet...get headers,y-pipe,cat-back.after you do that open up the intake system with a new air cleaner or cold air kit then after that maybe a chip or something...good luck

 

or what orangecrush says

 

im ripping out a 305 to put in a 400. dont waste youre time. ive dove so many minor mods to my motor, wasted hundreds of dollars and hours. no replacement for displacement. good luck!

 

how to get the most horsepower.. id say to build a turbo system is the way you will be able to get most ponies per cube on gasoline, on pump gasoline you are limited to about 100-120 horsepower/liter, which figures out to between 500 and 600 horses on your 305. I think everyone here agrees that those numbers are far more than your tranny (th200?), or engine will ever stand up to. but also that turbo systems might be a little more hastle than you want to get your self into, it can however be done relatively cheaply, : http://www.2quicknovas.com/turbos.html

a set of t-3 comp trim 60, exhausst a/r.63 from the junkyard (found on thunderbirds and svo mustange in the mid 80´s)should work fine up to 16 psi, putting you about 450-500 HP. and if you do like scott you should be able to bo it for under 1500$ albeit with a lot of work..

but if you are not prepaired take on that task and go that route id have to agree with the other posts. and just add displacement.

 

Here are a few links on 305 builds. These will give you an idea of what it takes, and what you get in the end.

<a href="http://www.goingfaster.com/spo/290hp305.html" target="_blank">http://www.goingfaster.com/spo/290hp305.html</a>

<a href="http://members.optushome.com.au/iroc-z/mods/320hp305/325hp305.htm" target="_blank">http://members.optushome.com.au/iroc-z/mods/320hp305/325hp305.htm</a>

<a href="http://www.goingfaster.com/spo/343hp305.html" target="_blank">http://www.goingfaster.com/spo/343hp305.html</a>

<a href="http://www.hioutput.com/tech/400hp/400hp.html" target="_blank">http://www.hioutput.com/tech/400hp/400hp.html</a>

As you can see, you can make more power. The high horse builds have compression ratios and cams that would make the motor a pain on the street. An "All Motor" street 305 with respectable horsepower will be quite a challenge. It's easy to get 400 hp from a 350 these days. Streetable and pump gas friendly. You can do the bolt on thing with your 305, and then transfer those parts to the 350 you build. Turbos, blowers, or nitrous will be your big horsepower items on a 305. Somewhere in the 400hp range is where you will start having duribility problems with the stock 305 bottom end. Dan