i need help deciding...
i've been to countless sites trying to determine which is better. i can't decide. there are limited choices available now, but there are a few popping up.
climax racing has a supercharger available.
xs engineering had a phatty custom turbo on a blue IS(like mine) that put (i think) 470hp to the rear wheels.
i think he had quite a few other goodies on that puppy.
turbos wear your engine and cost more to maintain.
superchargers don't have any lag time, and they are a little more "engine-friendly."
do you need an intercooler with a supercharger? or is it just an added bonus?

the more i find out, the more confused i get!

lastly, after adding all these goodies, when should i look into strengthening my hardware (ie. camshaft, pistons, heads, tranny, backend.....THE LIST GOES ON!)
where can i find all this tech data?

 

it seems like its a win-win situation

 

ok - here is my understanding of the ups and downs of turbo/super charging - someone correct my mistakes, bc im sure i don't fully understand all this

turbo chargers spin the turbine off of exhaust, so they don't kick in until the engines RPM get up a little bit(hence the turbo lag). turbo chargers tend to put up more Peak HP, but your powerband is not as balanced

super chargers are powered and don't use exhaust, but the increase in power is not as dramatic, but supplies for a broader powerband, and more even leveled.

intercoolers just cool the air because cold air is more dense with oxygen, and better for the engine, thus amplifying the effect of the super/turbo charger, but i do not think its necessary....

hope this helps a little/doesn't make me sound like an idiot

 

Here's my 2 cents

Supercharger for the IS is available- area 51, if you want power to come in all the time (belt driven) then get a supercharger.
Turbo the power kicks in at higher RPM's (turbo lag)

With the IS tranny being auto (until next yr) here are the pros and cons, the trubo might me easier on the engine because it will never really spool up until high RPMs and since the auto shifts low during normal driving there will be little additional wear and tear on the engine.

however, then your really not using the turbo to its full, unless you e shift all the time and keep the revs up.
the supercharger will give you more power lower rpm's but maybe more wear and tear (stress on engine) but the power will always be there.
I looked into both and still have not made up my mind, I like both , like the sound of a s charger and the sound of the turbo as well.

The next step would be to research the power increases to rwhp and if the tranny will handle it. Cause the tranny sucks as it is....

 

ok well turbos do give you more top end and the LAG so to speak is the time it takes the turbo to spool off the exhaust gases that run the turbo. Superchargers are run off a pulley system that connects to the belts in the front of your motor. There are ups and downs to both, to get into that is like knit picking, basically if you can find a good setup for either the turbo or SC you wont have to many problems at all.. I chose a SC but it will be puttin out alot of high end as well as the low end also, toyomoto and XS setups are very nice and proven to put out gobs of power. TURBOIS's car the blue one was dynoed at 415 at the rear wheels, the black IS from toyomoto with motor work and extensive tuning is puttin out High 500's at the rear wheels which is now prolly more like 600's. Yes the XS car did have some problems with the tranny which they have pretty much figured out now, Toyomoto is using a Haltech standalone computer for engine management so they had not problems at all with shifting whatsoever with minor tranny mods(IE valve bodies). I opted for both torque converter and valve bodies and possibly race clutches for my setup with SRT, I will be lookin for 450-500 at the rear wheels and in the winter go for the big numbers. As far as engine mods go you will prolly want to start with pistons rods ect.. after you are hittin high 400's to be safe, that is your call and the tuners call tho.

As far as the intercooler goes you cannot have enough cold air in your motor,this is what your motor wants to make more power, so if you are lookin to get a high HP setup by all means get an intercooler.

hope this helps you alittle. make sure you talk to all th tuners before hand so you are comfortable with them before you shell out all that cash and good luck... XS TOYOMOTO AND SRT I have all talked to and they are all on the level, i break it down this way, if you live in Cali go to XS NO DOUBT!!! FL or southern east coast call up toyomoto, and if you live midatlantic or north call up SRT they are in MD. you wont be dissappointed by any of there setups....

good luck Brian

 

For the average person, its hard to justify pullin the engine to rebuild, I am going to do it but hey.. area 51 has bolt on super charger boost 7-9 on pump, pick up a little power, this might be the way to go for the less than average tuner..... you need dIS also....

 

yep simple bolt on forced induction like the area 51 and SRT stage1-2 SC is prolly the best way to go for most ppl... you can do it your self and not worry about building your motor..

 

thanks everyone!

fairuza --- you mentioned a racing clutch...did you hold out for the 2002 5spd?

 

nope racing clutches auto trans still have clutches in them jsut a differ type of clutch....

 

I think when you consider installing a forced induction system (FI) you need to determine the ultimate goal of your project. You also need to consider the next important question - driveability.

Are you trying to create an hp monster for the track (drags or road course) then a turbo w/a lot of boost, intercooled, upgraded fuel delivery system, internal mods, possibly stand alone engine management.

Are you trying to just improve the power curve of the factory? Probably one of those stage I or stage II systems, either turbo or centrifugal s/c by the reputable companies mentioned on this board.

Turbos are generally more efficient than superchargers because they do not create any parasitic drag on the engine. So when you use a s/c, you lose some power to make power. The turbo just uses rubbish from the engine (exhaust stream gases) to create the power, it is not tied into the rotation of the engine.

Both systems benefit from intercoolers. Whenever you compress air to a higher degree than ambient, you heat it. Hotter air is less beneficial for the engine (less efficient). Intercoolings main benefit is too cool the intake charge of compressed air before it reaches the engine.

Personally, my goals are as follows. I want a system with broad usable power, reliability and not necessarily monster hp. I'm considering some type of Eaton/roots blower when one is available. This type of system has been sucessfully used in OEM applications by TRD and other car makers.

Find out what you want out of your car, don't just think of output numbers, then decide what type of system fits those needs.

 

I agree with risk once again... all depends on end goals and your application....me I will be using a Vortech type blower... but with much better efficiency...

 

how much punishment can the IS's stock engine/drivetrain take?
if i were to put a stage 1 blower from SRT, with an intercooler, plus maybe a greddy exhaust (or at least a bad-*** cat back system), would that require changing valve stems, piston rods, crankshafts...etc.?
i figure i'd throw a torque converter (maybe the dragon?) on her. but the blower and exhaust are my top priorities.
i'm new at this, and i'm still in my "research phase". the way my financial situation lies, i may be here for a while!
thanks again for the replies everyone!

 

nah u will be fine till about stage 4-5 then you want to fo your motor... you proly will want to lower your compression after stage 3 you can do a gasket spacer if need be...

 

You know what would really be helpful is if these FI manufacturers could state what boost levels will be at each stage.

By telling me that I woundn't need internal mods until stage 4 doesn't really tell me anything.

 

well srt stage 1 is around 4-5 stage 2 4-6 intercooled stage 3 8-10 intercooled and stage 4 10-what ever you want/..... dont hold me to these numbers but they are damn close to what the setups are