ok today i'm going to be posting tons of ?? on different boards cuz i want to learn something today at work (thurdays are always slow) so here it goes


everyone knows the well know saying "there is no replacement for displacement" but what does they really mean? i mean i know how a motor work i have watched step by step how it is done and i'm pretty sure i cous built my own motor if i had the room. i have put in a cam by my self on my motor so i know all about the vavle train (the heart of the motor) but someone help me out what is the big deal is.

i'll let Mr.Vader answer this one, since he's so much smarter than me, better looking to, and i know he loves it when someone ask for him by name.

See what you've done? You've hurt ugly ede's feelings

Displacement is in reference to Cubic Inches.

C'mon now ede...you don't type ugly

LoL i just like his name.....I am your Father!

All it means is, the bigger the "explosion" in each cylinder, the more power we can obviously produce.
the best way i could put it is, you can only stuff so much gun powder into one of those mini firecrackers (imports) before you have to upgrade to a M-80 (small block)....or a stick of dynamite (big block)to make anykind of serious power

Hey Mike.. Well you're gunna have to be a little more specific on that question.. Are you wanting to know how the displacement effects performance or how displacement is figured or what? There's all kinds of ways to answer that, the higher the displacement (cubic inches), the more compression, larger combustion chamber volume, etc. etc.

To figure C.I.D. just multiply-
Stroke x Bore x Bore x .7854 x cylinders (8 if it's a v8)= Cubic Inch Displacement

well i guess what made me thin to ask his ?? is that i read some place that by adding a twin tubro it makes your displacemant grow by 100%

Displacement =

bore X bore X stroke X 8 X 0.786 = CI's

(above answer) X 16.38 = CC's

It wouldn't make your displacement grow by 100%. The only way to do that is double the size of the motor. Perhaps they meant it would be equal to doubling the displacement... In other words a 350 with twin turbo would be equal to 700 c.i.d., in terms of horsepower, torque and compression... But don't quote me on that because I've never cared enough about turbochargers to even want to learn about them.. I'm just saying that is what they were possibly trying to imply.. You read it, not me

This would be a good time for a TRUE dragracer to comment on this. My uncle Bob, is currently leading the nation in the Summit IHRA super series points race for division 3. So, since he's a mopar man, you'll have to settle for my answer instead. LOL
"There no replacement for displacement" I've said this to MANY of imports at the track. Basically what this means is.....
A larger displacement motor has capabilities that exceed the smaller ones in many ways. Where you can really feel this difference is at 'top end'. Ex. When your doing about 80 or more and put it to the floor. A vehicle(assuming its setup right) with larger displacement will "Take OFF" at a high mph better than a (lets say) honda civic. Also, consider this. A 305 can be built pretty tough, but I've heard theres this "Brick Wall" effect just over 300hp where its EXTREMELY tough to get more power. A 350 30-over with a 4.030 bore seems to have almost an infinite amount of power potential with all kinds of various combinations from turbo's to supercharges, N/A to Nitrous. You could do this to a 305, but those motors seem to die quicker 'cause they can't handle all that stress.

The botton line is, the more space there is(in the cylinders), the more fuel/air can go in, more fuel means bigger "fire" or "explosion".....which is why most Big Blocks dont have to rev to the moon to make so much power