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Discussion Starter · #1 ·
I've been searching and reading up on supercharging and turbocharging, but one thing I seem to keep missing is what happens to a CAI if you boost? I imagine your CAI is even more important then, right? The reason I ask is: I'm leaning toward supercharging, but can I go ahead and do my CAI mod first (like a HS)? Will I have to get rid of my HS to make room for the SC? Thanks for any input, folks. (Not that it should make any difference, I have a '96 V6 MTX with about 41k miles.)
 

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If you go SC or Turbo you can use your CAI for a nice drain pipe extension, door holder opener or whatever. Turbo and SC are both forced air induction (FAI) systems, they cram the air into the engine and you feed her more fuel, open up the exhaust, etc. to make more horsies. :D
 

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actually, with FI you would cool the air with an intercooler... so yes, a new door handle... or maybe an antenna protector or something...LOL
 

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Discussion Starter · #4 ·
so where does the air get in...

thanks for the replies. i guess i didn't ask the question correctly. from where does the TC or SC draw air? through a CAI located somewhere else?
 

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it pulls the air through a filter, then blows it out through the intercooler, and then to the manifold...
 

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Basically what they are trying to say is that if you actually spend money on a pre-made CAI it won't be ablet o bolt on to the new in with a supercharger. The only kit out for a supercharger for our cars puts the SC where the battery is so you can see that the CAI wouldn't be able to fit any more. Most of the time you end up with a short pipe with the filter on it attached directly to the SC. Yes, a source of cold air is important but the SC is heating the air up as it compresses it adn it really should be cooled down by being run through an intercooler after going through the SC for beast results, depending on boost levels.
 

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Discussion Starter · #7 ·
thanks everyone.

what about life expectancy? how much wear and tear on the engine i can expect (if i boost to 5 to 7 psi)? i know that's a pretty open-ended question, but with regular maintenance, it is reasonable to expect to keep my engine for another 4 to 5 years? (presently, i have about 41k miles, and i don't race. i just want an increase in HP and overall performance.) and speaking of maintenance, how much (percentage wise) of the total installed cost would you all estimate is needed for the maintenance? also, what needs to be maintained? thanks in advance for any answers! (anybody :zzz: yet?)
 

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if you intercool, you can run a given boost more reliably.

5PSI intercooled should let you keep your engine running strong for at least 4 years...

as far as maintainance goes, im not sure about that one...
 

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if you think that question was stupid....what is the differance between TC and SC? what are the differant advatages betweeen the two? which one gives more HP? any and all info would be great.(if you cant tell i am new to this kind of thing and i want to know what i am doing.)
 

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xeon said:
CAI= Cold Air Induction
or Cold Air Intake.

Intake is an item while induction is a method.
 

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chris carmichael said:
if you think that question was stupid....what is the differance between TC and SC? what are the differant advatages betweeen the two? which one gives more HP? any and all info would be great.(if you cant tell i am new to this kind of thing and i want to know what i am doing.)
well...

Turbo:

Forces air into the engine by means of a turbine powered by a shaft which is connected to another turbine which is powered by the exhuast gases.

the shaft rides on a bearing and therefore needs oil supply.

overboost is prevented by a wastegate which is usually operated by an actuator hooked to a vacuum line. the wastegate opens and lets the exhaust gases bypass the exhaust turbine. also when engine speed decreases, overboost can occur and this is prevented by means of a Blow-Off Valve (BOV) which is on the intake plenum. when proper conditions occur the valve opens by means of electronics, vacuum, or the intake pressure itself, and releases pressure. this pressure is sometimes released into the unpressurized (before the turbo) intake and the drawn in again by the turbo. turbos generally have a higher boost pressure but move a smaller volume of air than S/C. this setup usually requires and definately runs better on low compression pistons (in the range of 7:1-8.5:1)

A Supercharger:

(centrifugal)
is driven by a belt, chain, or gears by the crankshaft. there is only a single turbine. oil is usually not necessary. because the turbine is driven by the crankshaft, the S/C is always pressurizing the intake plenum whereas the turbo takes time to "spool up" because turbine movement is not proportional with engine speed. there is a short period of time when there is a vacuum in the intake and the turbine speed is slower then nominal. overboost is prevented by putting the proper size pulley on the S/C.

there are other types of superchargers like the top-mount, which sits in place or on top on the intake manifold. the same concepts apply but the air is forced into the engine is a slightly different manner. rather than a turbine, there are fin-like stuctures that squeeze (IYW) the air into the engine. with this style you can do what is called "roots style" supercharging, in which the carburator sits on top of the supercharger and compresses the air AND the vaporized gasoline. this is illegal for street use but provides big time power gains. supercharging can be used with most compression ratios and its easy to use NO2 in conjunction with it, while in order to NOS a T/C'd engine, it has to be tuned VERY well.

there is one other type of supercharger but i dont know what its called or how it works. the above two methods are the most common. superchargers run better than turbos on high volume engines while turbos are more of an import fan favorite with the PPPSSSSSSHHHHHHHH of the BOV during shifts the whine of the spool up to intimidate other street racers.

anyone, feel free to add to this or correct any of my inaccuracies. ive never gone FI on an engine that didnt have it already and have never built a performance engine that was intended to be used with either (except my own, which isnt supercharged because i know of none that is in production phase but was designed to handle one). the most experience as far as hands-on that ive had is swapping out turbos and rebuilding them with tweaked turbines.

have fun...
 

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Discussion Starter · #14 ·
Stage36 said:
there is one other type of supercharger but i dont know what its called or how it works.
The other type is the positive displacement (PD) supercharger, like the eaton supercharger. the vortech is centrifugal. i think a PD is the way i will go. incidentally, knight turbos has both vortech and eaton. basically i got the following info from a now defunct website (http://ackthud.com/shawnfoggg/cs_vs_pd.html), but to summarize ... "the amount of airflow a centrifugal sc delivers increases roughly at a square of its driven speed. The PD is also called fixed displacement and produces air flow increases linearly with the RPM and should maintain full boost throughout the rev band. a centrifugally s/c car is going to feel very peaky b/c the boost delivery varies, but the PD supercharged car is mostly going to just feel like a much larger engine." (which is what i want). centrifugals, on the plus side, are smaller and are much easier to fit under the hood. oh, and also, i read somehwere that TC are quieter (besides the BOV) because SCs introduce more pulleys and belts. (makes sense, but to me unverified).

hope this helps.
 

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what i called top mount is PD... roots means placing the carb on top of the charger...

thanks for the PD clarification though.

and yes, a blower is louder, especially when driven by gears. a centrifugal not so much as a PD, because the PD, when used on a high dispalcement engine is driven by a 2"+ wide belt...
 
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