In regards to superchargers or turbochargers compared to N/A engines,

Say your car with boost has a CR of like, 11:1 (this is a random number). Does this create more power than an N/A car with the same CR? I'm having a hard time picturing it if cylinder pressure is the same, why it would be more powerful.

11:1 with boost is like playing with a hand grenade.

The supercharged or turbocharged engine makes its power because of having more air and fuel in the cylinders, not just because of the pressure in the cylinders.

I think he meant the effective ratio is 11:1, meaning 8:1 compression an "X" psi of boost.

Jody

ok ....... If the compressed pressure in both engines were the same (just before ignition), the supercharged engine would still have more air/fuel mixture in the cylinders and would make the most power.

hands down turbo's and blowers make more power than almost any conventional buildup that can be done.

Sometimes they are alot more work, alot more money, but often not.
Get it done by someone right or do it right yourself and your golden.
a friend of mine installed a 66mm turbo w/ intercooler @ 7psi on a 331 SB ford and made over 500 rwhp & tq with his clutch slipping the entire time.

I busted my arse to try to get 500rwhp streetably out of a chassis dyno and I missed the mark by more than the ever pessimistic myself expected.
If you all you want is power, and could care less about looks, a good turbo or blower setup will smoke most of the NA cars (I am generalizing, not trying to start a fight ok...), but they can be a headache if you don't know what you're doing. One more thing to go wrong is the way I see it.
Besides-- what are you gonna do with 750rwhp on the street? Kill yourself? Unless your racing, whats the point?

matt

11:1 and then supercharged. kapow!! ;) If you are thinking about using a power adder, why not use nitrous? I know "amateurs don't use nitrous oxide....you've got a heavy foot, you'll blow yourself to pieces" - Fast and the furious
LMAO :D . It's the best way to go IMO for a power adder.....especially if you don't have tons of $$$. Like myself. ;) But a turbo'd V8 is certainly something that can cause you to drool. ;) :D

Nitrous is not that cheap!!!..if you figure 4-500 for a cheap set up..than 50 bucks a fill up for N20..maybe 7 passes per bottle...thats 28 bucks a mile!!!!! Then if you add the "learning curve" expenses(pistons,rings,heads,blocks,carbs,hoods..e tc..)

is it true that if you start with a CR ratio of 7:1 and end up with 11:1 with aluminum heads you'll make more power than starting with 9:1 and end up with 11:1 using a blower.

also when does the engine reach 11:1 ? at 4,000 rpm at 6,000 rpm or right from idle with blowers ?

just pikin brains.
Lance

OR you could know what your doing....unlike most poeple.....from the start and do things right. Just a thought. lol I dont know why people are hung up on nitrous being bad...but I guess it doesn't really matter. It's initially less than running a turbo/turbo's or a supercharger. I mean you can't get a decent supercharger set up for less than $2500 or so. (as far as i know) But I don't really want to start a debate. But you can get a lot more than 7 runs on a bottle. Just saying.

but with a NA you always have tha power there, you don't have to feel up a bottle when you want to use it.

Cubic inches help too when you are not blown!!!

But as always, the great eqalizer(Sp?) is boost!!

550 plus inch standard deck BB's aren't out of reason now that you can buy any one of several big bore taking aftermarket blocks..

pdq67

Like I said...I don't want to start a debate on nitrous. It's just my opinion that N20 is a good choice for a power adder. Naturally there are other choices, and really it just depends on what you are working with. I mean if you have a 502 or some mild - rather built BB you don't need any power adders whatsoever to get some killer power. But for people like me, running a .040 327, nitrous can be a very beautiful thing. It's cheap (in my opinion), fun to use, can really surprise people during a race, reliable when done properly, and keeps you from having to run a higher compression engine, or engine with some other power adder when you don't really need the power. Yes...I know, you can regulate boost when driving a supercharged or turbo car. Just my opinion.