compression ratio VS forced induction

[tortzorz]

lets say u have a car with compression ratio 10;1, running 1bar
does that make the effective compression ratio 20:1? (obviously a little less due to heat etc) but is that what happens?

how come turbos can run such high boost?
if running 1 bar = doubling the compression ratio, wouldnt they detonate?
or that what an intercooler does, essentially bring the heat down to a level comparable to say 11:1 or whatever compression ratio would correspond to no detonation

and lastly, on old turbo cars with no intercooler, arent u just effectively trading off CR for boost?

e.g if u had 2 models of car, one turbo and one n/a
the turbo had CR of 8.5:1, the n/a 10.5:1
since theres no intercooler, wouldnt the amount of boost u can run depend directly on heat/compression?
so if u culd run a maximum of 10.5:1 on the n/a before detonation, wouldnt the amount of boost u can run develop 10.5:1 dynamic compression before detonation?

i understand that forcing air into an engine is better than drawing it in becoz of decrease of fuel:air ratio and stuff
but is that the only advantage? i would think turbo lag would b a big enuff disadvantage to offset that forced air advantage

plz feel free to elaborate on ur explanation if ive left anything out or u just want to speak ur mind, were all here to learn

[Zgringo]

First off compression is how a engine makes power. Without compression it's like pouring gas on the ground, it just sit's there and burns.The higher the compression the higher the power. Cams, porting, tuned exhaust, bigger throttle body's, turbo's, superchargers ect.ect. all these tools assist in putting more air into the engine. Now we come to the compression ratio. The compression ratio is the multiplacation factor burning gas makes under pressure on the top of the piston.
Here's a example. You have 3 engines:
#1 N/A with 16:1 compression ratio
#2 supercharged with 10:1 compression ratio and 10# boost
#3 supergharged with 6:1 compression ratio and 16# boost
All things being equal what's the difference in these 3 engines and power out-put? Nothing, nada, zip. There all the same.

http://www.goodvibesracing.com/Compression%20Ratio.htm

Now we all know you can't run 16:1 compression ratio with the gas we have at the pumps, so in order to run this we have to use racing gas, alky or retard the timing or other steps to prevent detonation.
Engineer's knowing the importance of compression ratio and knowing if you put more air into the combustion chamber of a engine you raise the compression ratio and increase the power. Now we have the age of the turbo's and superchargers, plus computers and aftercoolers to control the boost. timing and to keep the inlet air cool and keep the engine alive.
One problem with Turbo's is the 8:1 compression ratio designed into the engines. Till the turbo makes enough boost to raise the compression ratio you have no power. It's called turbo lag. You can put smaller turbo's that spool-up faster but lose top end power, or use larger ones and lose the bottom end. Your choice.
One way to overcome this is to run higher static compression ratio, say 10:1 and less boost. The problem doing it this way is you need to know what your doing so you don't turn your engine into a bomb.
If you run ADI or water/alky injection you can run unGodly amounts of boost. With this and Toluene you can run 5 bars boost and make 1000HP per liter if the engine internals are strong enough.

http://performanceolds307.tripod.com/id9.html

The reason engineers installed intercoolers which are not the best but kinda do the job is they knew people are lazy and wouldn't keep there water/alky bottle full and they'ed have a problem with blown engines. Water/alky is 10 times better than a intercooler ever dreamed of.

http://www.geocities.com/rad87gn/tech/alcohol.html

Drawing air into a engine ISNT any better than blowing it in, it just allows you to make more compression than one not blown.
There's lot's of old belief's that are just that, old belief's. They have no merit and don't apply to the engineering knowledge we have today.

If it wasn't for insurance companys and the NTSB we'd have cars in the 300MPH range by now running on panther piss.
There looking out in our best interest and protecting us from the evils of a modern high performance car. Go to Europe and look at the toys driven everyday not allowed in the USA. Thanks to our great leaders they let us have a choice of what they choose and direct the auto mfg. on what they can build.