Thread: 305 small block I NEED MORE POWER!

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I have a 305 small block and it doesn't seem to have any balls. It has a Holly 600 D-pumper carb and an 350 auto trans. Does anyone have any ideas on how to improve the performance on a tight budget.

What is it in? Is all else stock?
600 carb is fine, but with an automatic a double pumper is a bit much.
Tight budget..makes it tough.
cam....if you can do the work
intake....since you;ll have it off for the cam
heads....you may be able to get good used heads cheap. Emphasis on 'good' or else it won't be cheap

It also has a 2700 Fireball torque converter. Everything else is stock I think. Doing the work myself is no problem. Cam, Intake, and heads, what kinds? any suggestions?

Thanks for the reply. Is there a web site with info for these upgrades? Where should I be lookin interms of resources?

Unfortunately thats all I got right now. I'll eventually build a cobra with a 351 but the 305 will need to do for now. Any, I'm a toolmaker by trade and my father-in-law is an auto machanic so I'm not afraid to do any mods. I don't want to get to crazy but I do believe I could be getting a little more bang for the buck.
Mark.

"The bore is a very small 3.736", which means you can't bolt any good-flowing heads onto it because the valves would hit the block deck"

That is something you need to watch out for, but there are heads that will work on 305's. The problem with the stock heads is the tiny little intake and exhaust runners - they just won't BREATHE! GM made some pretty good heads for the 305's that were used in '75 and later Z-28's. They have 1.86" dia. intake valves and much improved intake and exhaust runners, but still have the 61cc combustion chambers. They are not overly plentiful, but they are not expensive either because the valves still aren't big enough to keep all of us 350 lovers happy.

You can put 350 heads on the 305 without worry of deck interference as long as you don't open the valves too far, but most 350's have 72cc combustion chambers and anything you gain in airflow through the engine would be lost by the lower compression ratio. You can hunt for some closed chamber 350 heads or early model 327 heads, but you will pay dearly for them and then spend more money having them reconditioned. Best bet for the money would be the late-70's 305 Z28 heads.

Given that Richard's comments are emminantly true, there's no substitute for cubic inches.

However, if you're absolutely married to the 305 you need to look at World Products heads. These guys are the kings of Chev heads (let the arguments begin!) and their prices aren't too far north of high quality rebuilding costs for stock heads. Check this link: http://www.sallee-chevrolet.com/Worl...uer_Heads.html

Here's a link to a synopsis of how Car Craft built a 325hp 305: http://www.goingfaster.com/spo/325_h...chevrolet.html

Great info, thanks guys. Had the beast out tonight. Sounds like I need to get it dyno'd then start my journey. Anyone else with input?

tuned port injection...the only problem is that it will set you back about $2500...so if i were you i'd stick with gettin the motor to breathe better. if ya think bout it...it is pretty damn hard to run fast while breathing through a straw. depending on how tight of a budget your on, you could go with a roller setup, or aluminum heads...hell, maybe even both sooner or later.

Richard has the best idea for someone on a tight budget. Buy a good 350 engine and put your double pumper on it. You would have to spend a lot of cash to get a 305 to perform as good as a stock 350.

I agree with Al.....go to the nearest junkyard & take your father- in- law with you & pick out a low mile 350 for a couple of hundred bucks. LESS than you will spend on the HEADS alone ! $$$ you can spend elsewhere on your rod....Good Luck

Hey i thought i'd provide some eye candy.
But i can't post the pictures.

I put some photo's on file , just click the camera and tell me what you think.
Mark

Click on the "new reply" button at the bottom of the last post. Below the text box it says attach file. Hit the browse botton next to it and add the picture.
AL

IF THE PIC YOU POSTED IS THE COBRA WITH THE OVER PRICED PAINT JOB...YOU SHOULD CAN THE SMALL BLOCK AND STUFF IN A REAL MOTOR... FORD MADE PLENTY OF COOL BIG MOTORS THAT WOULD BE RIGHT AT HOME IN THAT CAR...YOU COULD GET A FE 390 AND DRESS IT LIKE A SIDE OILER 427 AND SCORE MORE POINTS THAN THAT CHEV....BESIDES...YOU SAY YOU HAVE NO MONEY??? THAT CAUSE YOU SPENT IT ALL ON THE PSYCODELIC PAINT JOB........BUT THATS JUST ME, DIE HARD VINTAGE MAN