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I'll stick with my Minnam turbo/Shiv/Own creation setup that I have now. Why mess with something that already works.
 

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I don't think that THAT many people are jumping on the bandwagon, i think a lot of people have been waiting for a supercharger kit that works and doesn't require permanent modification to your vehicle, they are just getting excited now that there are a few kits nearing completion.
 

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aaah,. those young'ins that don't remember rimmer. now where's my cane? matlock is on in twenty minutes.
 

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Everyone is indeed jumping on the SC bandwagon. Why? This is my question.


What makes a supercharger so much more likeable than a turbo setup? Is it the name; supercharger, does it sound cooler?

Does everyone who wants a supercharger think that their engine is less likely to blow up than a turbo-engine?

For those of you who do think that, you have something coming. Turbo's and SC's in the end do the exact same thing, increase the amount of pressure in each cylinder. If anyone thinks a supercharger does it in a safer way, then you are sorely mistaken.

Maybe its just the fact that no one (that I know of) has ever blown a 2.5L motor with a supercharger. Once people do start doing this, I am sure mindsets will begin to change and people will come to the conclusion that you have to be just as careful with a SC as you do with a turbo.

I don't mean to nag, but how many problems have you had with your car 5252? Tranny out something like 5 times, a few less for the engine, right? To make the power you really want your going to need a larger unit, right (the M-62 just isn't cutting it)? Same thing with the SC's. When people want to start making huge power (and they will) they are going to realize the Rotrex unit that came with the kit just insn't suffice anymore. Well, for as much as I know about SC and bracketry, I am guessing its gonna require a whole new bracket be made to house the larger unit (has this issure been addressed in the thread?). Its not quite as easy as a turbo, where you pull some lines, undo some bolts, and drop the new larger unit in.

We'll see.


Graham


- Its not that I don't like SC's, I just believe some people are misled by a supercharger over a turbo.
 

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what Graham said is correct.

i have something to add to SC. just remember that you are taking away some power to make more power vs. TC, you are just recycling your exhausted energy.

jz
 

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"I don't mean to nag, but how many problems have you had with your car 5252? Tranny out something like 5 times, a few less for the engine, right? "
Right. but not because of overboost. the engine started with an oil leak. then a blown head gasket that was a design flaw on something experimental. i can't remember the third prob. the trans is a chalak dog box that had problems with 1. selector fork geometry. 2. i tried it without the interlock mechanism. 3. chalak neglected to tell me to relieve the case so the interlock mechanism would clear. 4 rear main seal looksee for leaks. etc.
"To make the power you really want your going to need a larger unit, right (the M-62 just isn't cutting it)? " I think changing to a snail cased or rotrex twin will be easy to poke into the same spot, roughly. i know a fabricator with a pipe bender etc. and i like the idea of a shaft driven snail cased blower. besides, it's pretty stout at ten lbs. i have yet to dyno it.
"What makes a supercharger so much more likeable than a turbo setup? Is it the name; supercharger, does it sound cooler?" hell yeah.
1. everybody and their dog has a turbo. 2. torque. not horsepower. 3. chicks dig superchargers. :)
"Turbo's and SC's in the end do the exact same thing," in two different places. a turbo hooks up at the top and ramps up. a blower hooks up at just off idle and falls off at the top. this is very useful in traffic. a turbo gives you top end and for some reason unknown to me this is very useful in England. ( they covet top end and don't understand our yank taste for torque and dragracing and such) one last point any belt derived boost over eight-ten lbs will fuxor your trans. this is where the project gets expensive. and is probably the biggest difference.

:):)
 

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i am not here to support one over the other. my philosophy is one of each! too bad you're in fla. i think you could use a ride in the frankenscooby.:) :)
i just stuffed in some really nice sparco torino knockoffs.
 

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and wizb, "yeah and a turbocharger sounds better"
sorry dude my three inch exhaust has no turbo impeller to munch up the exhaust note. so i would have to disagree. after hearing all motor cars and turbo cars on the dyno and at the strip...... the buick grand nationals sounded pretty gnarley but.... if you mean the blowoff valve, they can only be heard in traffic. they get drowned out at the strip.:)
 

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Kent's S/C will be less of a pain to install. No up/down pipes. No oil return line, I don't have to worry about boost adjustments.

I like an S/C for the following reasons:

1. Kent's sounds easy to install.
2. I want to be different. To many Turbos running around.
3. I love the whine of a S/C.
4. No modifications to my exhaust system.
5. Pop the hood and instead of "oh it's another turbo" it's "is that a super charger!?".
6. See #2.

I know exactly what I am in for and the possible outcome of adding more power. I have been waiting patiently for someone to create a kit. I could have 300hp possibilities for going turbo but turbo's are becoming so main stream now. Again. I want to be different.

It all comes down to personal preference. Nothing wrong with those wanting to chose an S/C over a turbo.
 

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First of all, your stereotyping turbochargers. I don't think your familiar with my turbo setup. Its custom, utilizing an RHB5 VF-10 Legacy turbo. Undersized for a 2.5L? Yes. Full boost by 2100 RPM? Yes. 5252, I don't need to tell YOU that there are ways to make turbo cars spool at quite low RPM.....;)

If you rode in my car, your first reaction would be......SUPERCHARGER, this guy has a SUPERCHARGER! Right up until you hear the BOV, that is.

Fact is, my car runs out of power up top, much like a blower. But, I make huge torque (quite a bit more than HP as well, from guys who have same setups) mid-range and down-low. When I accelerate from a light, for instance, the SECOND I release the clutch the turbo is spooling, and its VERY audible. I have never, and hopefully never will experience boost lag, its ALWAYS there the second I need it.

Enough about my car, I'm just using it as an example. Your right, there are many turbocharged cars out there, but there's a reason for it. Greater efficiency. There's no valid argument that using energy (velocity of exhaust gas) to create more power is not more efficient than drawing power from the engine via crank to create boost. When speaking of cars, friction is not our friend, the less the better. This is a fact.

5252, I live in Texas now, not FL, so maybe someday I will get the chance to see your beast, and get a ride.

Your debacle with creating more boost just sounds like too much of a hassle for someone like myself. Having to have new pipes bent, possibly a new casing is simply just not as easy as replacing turbo. I'm calling it now, this is something that will become of concern about Templars kit in the future, more boost.

Does a supercharger sound cooler? Now thats simply personal preference. I think I need to get a sound clip of my car. People just go crazy after they hear it. The only thing I can think of is the Puegot 206 WRC, sounds very similar to that, just louder! (Its because its so small).......:D


spshultz: I don't doubt it will be less of pain to install, in the short run that is. My friend, you WILL get the boost bug. It happened to 5252, its happening to me, it happens to everyone. Your gonna want more power, the question is will be able to get it without having to replace your blower?

You say turbo's are mainstream. Not in RS's. My educated guess is no more than 200 RS Turbo's in the US. Is this mainstream to you?

No modifications to your exhaust system? What are you talking about? Do you plan on keeping the stock 1 3/4" piece of crap? Just FYI, the turbo kits on the market today don't require mods to the exhaust, all you have to do is bolt up an aftermarket unit to the midpipe/downpipe (not sure, mine is custom).

ALL reactions to my car (because there are so few RS Turbo's) are enthusiastic, everyone turns their head for a good looking RS-T. It might help that mine is custom.

If you want to stay exclusive, do a turbo and a supercharger......:D . Soon enough there are going to be S/C RS's running around, and most all of them will be the same DNT Performance kit.


I'm enjoying this debate......:)


Graham
 

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Geeze. I didn't mean to start a war or anything. I just was pointing out what i''ve been seeing. I am excited too about the s/c kits about to come out. On another note, this is probably the most replies i ever got on my of my threads.
 

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this isn't war. this is just about what everyone feels about TC and SC.

Your right, there are many turbocharged cars out there, but there's a reason for it. Greater efficiency. There's no valid argument that using energy (velocity of exhaust gas) to create more power is not more efficient than drawing power from the engine via crank to create boost. When speaking of cars, friction is not our friend, the less the better. This is a fact.
i totally agree on that. i guess i lean more towards a TC. it doesn't really make a lot of sense to me in robbing away 20hp from the crank to power the blower, and making an extra 50hp (might be wrong on the numbers, but you get my idea). on the other hand, turbocharging doesn't rob the car of any power, but it'll make that 50hp easily.

but it is true that it is based on personal perference. i have driven a MR2SC (13 or so psi), and a RX7 Turbo II (17psi). i actually love both. the MR2 is great for city driving. i remember, right off the line, HOLY SHIT 10psi. it's pretty hard for a turbocharged car to see 10psi just like that, not impossible, but hard. only problem, the boost went to 14psi, and it sorta stay there. great off the line punch, but that was it. on the other hand, the RX7 TurboII just got more and more exciting at higher RPMs. after 4.5krpm, the turbo would just scream and throw me back into the seat. i guess there are pros and cons about both TC and SC. yea, like what graham said, let the debating begin!

jz
 

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I don't mean to dispell the notion that the power to turn the turbo is free, but...

One cause of the inefficiency comes from the fact that the power to spin the turbine is not free. Having a turbine in the exhaust flow increases the restriction in the exhaust. This means that on the exhaust stroke, the engine has to push against a higher back-pressure. This subtracts a little bit of power from the cylinders that are firing at the same time.
This is from an article on how turbos work.

Also if you are using a centrifguel SC (which is primarily a belt driven turbo), I have a hard time believing it takes 20hp away from the crank to turn it, if this true then so does the alternater and AC unit. Please feel free to correct me if I am wrong on this.

I do agree that for those that will eventually get boost hungry an SC is not the answer, but for those that will be happy with 4 to 7psi of boost the SC option will be an easier way to go, plus don't forget all the added torque you get.

Just wanted to chime in with my 2-cents.
 

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i was just putting numbers in as examples. i doubt it takes like 20hp to power a SC.


jz
 

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OK, I can understand that. I can also understand why some would prefer a turbo system over a supercharger. I think there is a deffinite place for both systems un the Subie aftermarket. Personally since we are building a rally car I would prefer a SC for what it offers. Dispite what some might think HP is not everything especially in the dirt/gravel.

PS. The dialog on this board has really started to come around as of late. I would really like to see this board become what that other board (now full of Honda/Acura converts - will not name it) once was...
 

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I have never said that I disliked turbos. Deadbolt and I originally decided to put a centrifugal supercharger on the 2.5 because no one had done it. Next week, I will be the first. There are many arguments over which is better, turbo or supercharger, and then you can get into centrifugal, roots, whipple arguments on the supercharger end of it.

All systems have pros and cons.

Turbos are the easiest systems to increase boost on, and they have less parasitic loss than a supercharger...however, they still do have parasitic loss (just not as much) and they are more difficult to manage with basic engine management. Scooby South ran a Minnam stage II for some time with no trouble, then one day boost spike and pop...there went #3.

Roots type blowers have the best boost response and most instant power of any forced induction system. The drawback is that they have horrible adiabatic efficiency, which means that they heat the air a lot more than physics demands for the compression they give you. Therefore they can be very prone to detonation if you are not extremely careful with the
Whipple chargers, or Autorotors, work in a similiar manner to Roots type blowers but are more efficient. They still fall way short of the efficiency of a turbo or centrifugal blower.

Centrifugal blowers have the highest efficiency of any form of forced induction. The boost is not "instant on" like a roots or whipple style, but there is still no lag. If the engine is turning, they are providing some, albeit a small amount, of positive manifold pressure. They are easy to install and will be lighter than a roots or whipple system, and even lighter than a turbo system. However, once a turbo spools, it can pretty much maintain max boost throughout the remainder of the rpm range. A centrifugal supercharger simply provides more and more boost the faster it turns, therefore, max boost is only achieved at the rev limiter. However this drawback does make fuel and iginition control much easier to tune because they can be done based on RPM.

Another benefit to the supercharger can be found on a tight race course such as in autocross. I have witnessed almost every turbo car I have ever seen autocross lose boost when entering turns that don't require a downshift. With a supercharger, the boost is there and so is the power. Even a centrifugal supercharger will be turning boost.

The main reason we decided to go with the centrifugal is that we felt it would be an excellent match for the 2.2 and 2.5 engine. The powerband is extremely narrow, although torquey. Highway cruising is generally done at 2700 to 3000 rpm, depending on speed, and the Rev limit is only at 6250. With a centrifugal supercharger there will be a usable amount of boost anywhere in the powerband, but there will be no dangers of boost spike, and the risks of detonation will be greatly reduced due to the increased efficiency of the centrifugal unit.
 
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