I own a 305 TPI and was just wondering seeing as there is a 15% size difference in the 305 vs. 350 does that mean that with exact same parts a 350 will make only 15% more power
ex. 305hp vs.350hp thats 1 hp/ci
ex2 335.5 vs. 385 thats a 1.1 hp/ci
and so on and so forth or am i missing something ?

 

being short no! there is a lot more than the size. the cyliders are smaller in a 305 so it actually shrouds the valves. giving the 350 an advantage in that alone not to mention the extra displacment the 350 has on top of that.

 

An advantage in what high RPM, low RPM, all over the power band
is a 350 block stronger?

 

Team FTS wrote:
"An advantage in what high RPM, low RPM, all over the power band is a 350 block stronger?"

The 350 is strangled by the TPI system stock from GM which accounts for a portion of why the 350 only makes a few more HP than the 305. The 350 has a real grunt at low RPMs but looses power at a lower RPM (4600-4800)over the 305's 4800-5000 RPMs.

 

Sorry I should have been clearer I don't mean stock, I mean mod for mod two motors built with the same parts same intake, cam heads exhaust you know working in the same power band and what-not, will there theoretically be a 15% power difference or will it be more pronounced that the 350 is "better"

 

Theoretically, yes, however, in the real world, theory only goes so far.

If you take two engines, with identical setups, the engine with more displacement will make more power. Will this be proprotionate to engine size? Probably not. However, if you OPTIMIZE the setup to the specific engine, you will make more power. (matching parts to build power/torque in the same rpm range, heads, cam, intake, etc.) This can be taken to real extremes as well....... Just depends on what you want from your engine, and how much you are willing to spend on it. Dollar for dollar, you will get more performance from the larger engine.

Nothing replaces displacement.....

There is no substitute for cubic inches........

And a number of other old adages that I will not go into.....

 

Thanks that just what I wanted to know dollar for dollar I know 350 is more powerful but if ultimate power is not what you are going for the 305 should handle that task, but yes dollar for dollar the 350 wins but if you already own a healthy 305 why scrap it?