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Discussion Starter #1
I get asked this frequently.
the question usually goes something like

" look Ive got a VERY LIMITED budget, which should I go for,
great heads or a good large displacement short block,
IVE only got $1500, or $2000, or $4000 to work with??"

first ID point out its foolish to buy parts you won,t want in the finnished engine, and thinking thru the progression and steps will help make sure your not stuck with a non-running car for weeks or months at a time!

well having been this route a few dozen times (personally) and many more on other guys engine combos... Id put my two cents worth in,
OBVIOUSLY youll need BOTH to maximize any combos potential, and it depends a great deal on how large a displacement increase over stock your thinking about,
now if your only going from a 350 to a 383, the heads will obviously be a good value,as better heads and a matched cam can boost the hp noticably,but if your seriously building to maximize the torque and hp in the complete project and your eventually going to build the engine to maximize the power..
and if your thinking about a serious upgrade in displacement , say from a 327, to a 427 in a sbc or a 396 to a 496-632 in a bbc,...
I ALWAYS suggest going for the large displacement short block thats well put together FIRST.
youll never make killer hp without the good heads but you can use stock heads on a well built short block to make killer low rpm tq UNTILL you can budget and save for the heads you want, ESPECIALLY on a BBC combo as the heads, even the peanut port door stop design heads, flow more than the VORTEC sbc heads ,now of course theres the potential problem of differant clearances, and compression ratios with differant pistons and combustion chambers, but if it will fit and fuction ID go FIRST for the displacement an have a driveable car with the old heads while saving for the better ones. YOULL NEED TO THINK EACH STEP THRU CAREFULLY.

lets assume youve got a 350 hp 396 in your 66 chevelle, nova or camaro, and want a killer combo.
youve saved up $3000-$4000 and its burning a hole in your pocket, now you can buy a 496 short block or killer heads and a cam, and theres little doubt that the killer heads and cam sellected correctly will make more power than your old heads and cam on the new 496 short block...but think it thru THEN WHAT?
in a few months or years as your budget allows, youll want to upgrade, if the heads and cam were sellected for the 396 its not likely that they are near ideal on a 496 with its greater displacement and lower average rpm range..
if you sellected the short block first, the heads and cam can now be sellected to match.
its simply faster and easier too swap heads on a good short block than it is to swap short blocks out at a latter date when the funds and parts become available

keep in mind the displacement and compression dictate to a large degree the torque, while the cam timing and heads flow rates effect the rpm range and peak power potential that displacement can reasonably achieve on a limited budget.

966 Posts
For the person who wants IMMEDIATE performance gains that they can actually feel and see, I would pick NEITHER as far as heads or short block. The best "instant performance" gain you can do to ANY car is to put in a stiffer rear end gear (3.73, 3,91, 4.11, etc). The problem is folks want performance AND economy. If you are running a 4 speed stick or 3 speed auto, a stiffer rear end gear will also cost you more $$$ at the gas pump. Especially because you will be "getting on it" a lot more to lay those two black skid marks that you couldn't do before :laughing:
Nothings for nothing and performance comes at a price. :thumbsup: :thumbsup: But a different rear end gear is a LOT cheaper than heads or short block.

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