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Discussion Starter · #1 ·
With lag free low presure turbos already available, from big mfrs, with warranties any everything, Why are people still holding out for Superchargers?

Just wondering.
 

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There are always plusses and minuses to each form of forced induction, and I personally have no problems with turbos. i like them a lot, but as I said, they all have plusses and minuses.

First off, when you look at a "lag free" turbo, you are either a)still going to have lag, even though it will be greatly reduced, or b) run into a turbocharger that is to small and runs out of steam up top.

But, since you asked, I feel there are several reasons that my customers are anxiously awaiting the supercharger.

A centrifugal supercharger is far more efficient in regard to heating of the compressed air than any other form of forced induction. Therefore, you do not lose as much hp of the compressed air due to the air molecules heating up during compression.

Any supercharger, even a centrifugal is truly lag free. Any rpm, when you push the throttle down you will get immediate positive manifold pressure.

One of the arguments I hear is that superchargers take engine power to operate, while a turbo is "free energy" that is wasted anyway. This is not true either. When you place a turbo in the exhaust path you are placing a HUGE restriction in the path of the exhaust gases as well, which creates backpressure. Backpressure, despite what you have read or heard, is a BAD thing. Go ask racing engine designers how much packpressure they tune into their exhaust systems. Work is the key to horsepower, anytime engine work is lost to doing something else, that work can no longer go to the wheels. When the backpressure of a turbo is created, the engine must work to push those exhaust gases backwards. Granted, monster uppipes with no cats, and turbo back exhausts that allow the turbo to spin more freely allowing the gases to flow better, but there is still restriction, therefore, lost horsepower. Perhaps not as much as is lost in the belt, but it is definately not "free."

Another reason that I feel the DNT supercharger kit that is coming out will compete quite well with similiar boost range turbo kits is weight. The kit should easily weight 40 lbs less than a turbo kit.

Also, when you say that the kits are warrantied, what are you speaking of...that the parts are warrantied. All of the parts in our kits will be warrantied. I am not aware of any aftermarket turbo kit warrantied against damaging a car though. As a matter of fact, most state in the literature that comes with the kits that they are not responsible for damage resulting form improper installation etc. etc.

A supercharger kit should be a great deal easier to install and maintain than a turbo kit as well.

Than of course, the only "complete" turbo kit I am aware of is the AVO sport kit, which I believe you sell. The price on this kit is over $4000. The price on the supercharger kit that so many of the members of this community are waiting for will sell for under $3500, hopefully closer to the $3000 mark. The extra money will pay for the upgraded clutch they need, plus a little.


Then of course there is the other, less technical reason that I believe so many of my customers have waited and are still waiting. There are lots of people who just want to be different; to follow a different path. To be honest, that is why myself, Jerry, and later on, Porter, started down this path. We wanted something different. Who ever heard of a Subaru with a centrifugal supercharger? Well, now it is a reality, and there are more to come soon.

Sometimes what happens to a car is not all based on dollars and hp numbers. Sometimes it is based on a sound, a look someone likes, or just an urge to be unique. But it is nice to know that if my customers want the sound of a blower, the uniqueness, and they like the price of the kits, they will still have a good deal of horsepower to back it up...with no lag (for real)

Kent
DNT Performance

This was not intended as a flame, this was intended to provide my opinions to the question you asked.
 

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RSS Hottie
'00 RS
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Well since I've been involved with the sc v. turbo debate for some time now, I'll elaborate on Kents post.

The supercharger and kit Kent has put together is exactly what I want, that goes for most of us. Keep in mind he's kept us updated for over a year on this board and asked us what we wanted for a kit and put just that together.

The only reason I can add pro-sc is that rarely a turbo kit is ever a kit. I don't need to spend 3k on a turbo "kit" and then spend another 3k on what I need to run it and keep my car from falling apart/ While DNTs kit with have everything but the clutch required to run the kit. In a price range I can afford.
 

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RSS Hottie
'00 RS
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Angel said:
Well since I've been involved with the sc v. turbo debate for some time now, I'll elaborate on Kents post.

The supercharger and kit Kent has put together is exactly what I want, that goes for most of us. Keep in mind he's kept us updated for over a year on this board and asked us what we wanted for a kit and put just that together.

The only reason I can add pro-sc is that rarely a turbo kit is ever a kit. I don't need to spend 3k on a turbo "kit" and then spend another 3k on what I need to run it and keep my car from falling apart/ While DNTs kit with have everything but the clutch required to run the kit. In a price range I can afford.
P.S. who sells this lag free, warrantied turbo kit?
 
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Discussion Starter · #5 ·
"The only reason I can add pro-sc is that rarely a turbo kit is ever a kit. I don't need to spend 3k on a turbo "kit" and then spend another 3k on what I need to run it and keep my car from falling apart/ While DNTs kit with have everything but the clutch required to run the kit. In a price range I can afford."


AVO has COMPLETE turbo kit. no extras, 'cept clutch , needed. I do not know who you have had to deal with in the past. I assure you AVO is complete. Has warranty on parts defects. 'Lag Free' means very little lag. About the same amount of lag as a supercharger.(you should drive this thing) With 6psi by 2300 AVO should have about the same performance.


I had intended this to be a thread about Turbo vs. S/C in general not AVO vs DNT. There are others working on superchargers as well as others with turbos.
:boxer:
 

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i'll chime in because i'm not selling anything or looking to buy. I think both Rallitek and Templar have stated their positions quite well and this really is an old debate, so I'll just stick to my dorky guns. One really cool thing about a turbo (note, from a very dorky point of view) is its efficency. Like Templar noted, it is a restriction in the exhaust and this isn't the best, certainly. However, in alot of cars, nearly half the energy produced in the combustion chamber waves goodbye as it hurls past the exhaust valves. The cool thing about a turbo, even if its not being used for high performance uses, is that it exploits this otherwise wasted source of energy and uses it to compress air to feed to the engine making it much, much more effiecent. a supercharger just can't compete with this. those belts on the funny cars and such sap more hp then my engine makes :eek: obviously, on a street set-up, this is not so pronounced but its still there, making the whole system less elegant through the old dork goggles. if you have the money, a really nice turbo will be making plenty of boost by the time you need it. when during a race of any kind will you be bellow 2300rpm, especially with the gears on a RS? and if you have enough money to often replace your very expensive, snazzy turbo, there's always anti-lag :biggest: then again, there is a L with a s/c 2.5 that rally-x's out of chicago. very, very fast.
 

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RSS Hottie
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RalliTek said:
[BAVO has COMPLETE turbo kit. no extras, 'cept clutch , needed. I do not know who you have had to deal with in the past. I assure you AVO is complete. Has warranty on parts defects. 'Lag Free' means very little lag. About the same amount of lag as a supercharger.(you should drive this thing) With 6psi by 2300 AVO should have about the same performance.


I had intended this to be a thread about Turbo vs. S/C in general not AVO vs DNT. There are others working on superchargers as well as others with turbos.
:boxer: [/B]
I'm not trying to compare the 2 companies I used DNT as an example because aside from the rimmer kits, he is the closest to having a kit done. Yes other people are trying to come up with sc kits, but they aren't letting me be involved in what I'm paying for aside from a "we're working on a sc project', and I know how much money I'm spending with this kit.

Did you see larry's rant thread about why noone is buying turbos, very similar to this? check it out on the other board it may answer some of your questions better.

My personal choice is not to turbo a 2.5, even at low psi, it's just not reliable on that block in my eyes. I'd do a wrx engine swap first.

I'm sure others can give you better reasons then just cause they want to be different.

I'd really like to see a low lag turbo that's reliable on a 2.5 block. Who has one on? Show me the numbers for it. Turbos just aren't selling as well anymore because of all the people with rs-t problems. You're gonna have to prove the AVO kit is reliable. Send me one and I will test it out.:)


Another thing is while so many are "wroking on turbo/sc kits" Not many ever finish, think about the market you're selling to... 2.5rs

You run into alot of issues between year with these cars not to mention the fact that they're just aren't alot of them out there.


So yeah I wasn't trying to make this a DNT v AVO thing, I use examples that are available to me to compare.
 
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Discussion Starter · #8 ·
Anyone have any drag racing experience? I have always built road/rally cars. Seems like the big V8 guys run S/C. The import drag cars runs turbos. Any thoughts why no turbo dragsters? Why no blowers sticking out of Hondas?(or at least very few of each type)

sean
 

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Well, there are several reasons for both. One of the biggest reasons that none of the top fuel guys run turbos is that turbine powered superchargers (turbochargers) are illegal in top fuel and most of the other big displacement classes. Of course, twin screw and centrifugal supercahrgers are also illegal. Mainly so there cannot be too much variance in the cars. The monster superchargers that are on the big, ultra fast drag cars usually require several hundred horsepower just to run, however, they produce enough boost that the cars are producing thousands (plural) of horsepower. Even if the turbine powered, or centrifugal units were legal, which tehy were at one time; the cars would probably still be running the huge roots blowers, or maybe twin-screw type, because of the massive, instant, high levels of boost they produce. A turbo large enough to produce the Horsepower numbers these cars are producing would have a large amount of lag as well, which these racers don't want. Also, if you look at the exhaust designs of these cars, it would be difficult to fit a turbo in the design, and allow anywhere near the exhaust flow required to keep that ugly backpressure from showing up.


The smaller import classes run turbos because of the incredible high hp needed would require a MASSIVE blower. The tiny, high reving engines that they are equipped with do not really have the torque necessary to turn a blower of the size they would need.
 

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RalliTek said:
Anyone have any drag racing experience? I have always built road/rally cars. Seems like the big V8 guys run S/C. The import drag cars runs turbos. Any thoughts why no turbo dragsters? Why no blowers sticking out of Hondas?(or at least very few of each type)

sean
Check out the 1/4 mile forum..alot of us drag race...imports domestics and there's even one or 2 guys on here that race dragsters.

They'd be happy to answer some of the more tech. questions associated with drag racing on a larger scale then what most of us are able to do.
 

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This is an example:

If it takes 30hp to run a compressor via the crank shaft it will only take 5hp to run a compressor via a turbine off the exhaust gasses.

This used to be the case but now with the newer technology the energy required to run a compressor via the crank is a lot lower.

I personally don't like the idea of a centrifical super charger. IMHO the only way to go is screw type or roots.

There are quite a few civics running around with the Jackson Racing supercharger which is roots type IIRC and the Vortech kit that is centrifical. I hear more about the supercharged civics than I do about the turbo'd variety.

Templar, there wouldnt be much of a problem using four turbos on a massive engine making that type of power.

I believe the biggest reason why people are interested in the supercharger is because it is different.



-Chav
 

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Meany Head
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I'm personaly interested in an SC (like Templars kit) for 2 primary reasons... Reliable and Simple. The Centrifugal SC can be installed before the Throttle Body (Like a Turbo), so it's install is nice a easy. And the fact that there is no messing with the exhaust, the install is much simpler than a Turbo also. Plus, it's well known that a Centrifugal SC is very reliable at producing bost. I don't care about producing the max amount of possible power out of my stock EJ25, I just want more, and I want it to be simple.
 

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Best part of the S/C kit?

It's a feature that came in later on, actually, perhaps almost on accident on Templar's part. The S/C they're planning to use has it's own oil resevoir, no more welding oil pans, no more worrying about oil pressure, oil feeds, oil type compatibility between engine and induction compressor. S/C oil reservoir blows chunks and dumps it's oil? Engine isn't bone dry. You lose your air intake, and hopefully nothing worse, so your engine goes limp, but that's always better than seizing..

The S/C kit, in theory, seems a much simpler install than a turbo. Templar also took the time to make sure the S/C fits in "empty" space, if I recall. Most Turbo kits out there require some hardware relocation. Usually the cruise control, again if i'm recalling correctly.

The heat efficiency is really the only technical advantage I could give you. The efficiency rates that Rotrex I believe it is are claiming are pretty flippin amazing in the compression world.
 
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Discussion Starter · #14 ·
If the S/C option has relaibility and simplicity , why are all the WRC cars turbo? Why are there all kinds of turbo kits and no S/C kits available? I think the S/C would have the torque advantage. You just don't see belt drive induction in road racing very often. Any thoughts?
 

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relating street cars to race cars is folley. a race car is purpose built to a set of rules (rules which usually frown upon un natrual induction). a street car has to be much more variable in its duties, but isn't nearly constrainted (except on budget). its apples and oranges.

WRC cars use turbos, and no one is going to argue that a turbo isn't more effiecent then a supercharger. but WRC cars also have $100,000 engines. not to mention anti-lag, which takes care of that whole lag issue once you're moving. at the same time though, they have a nasty little 32mm turbo inlet restrictor to prevent them from developing too much hp. when turbos were unrestricted (group B basically) they made lots of hp and had horrible lag, leading Lancia to employ both induction methods on the Delta S4. granted, technology has come a long way in reducing lag, so i doubt you would ever see this again. F1 turbo cars were the same way. they made 1000bhp/liter in qualifing trim but have very, very peaky power bands and huge lag. once again, i think alot of that could be reduced these days (look at the Champ cars back before they sucked). and then some racing series allow either one (with various penalties generally associated). Look at the Speed World Challenge. you have a twin turbo S4 duking it out with a supercharged NSX. if they didn't get weight penalties or have inlet size restrcitions or boost level restrictions, everybody would be running a turbo because you can make absurd amounts of power with it and lag has become much less of an issue these days. for low boost/restricted applications, a supercharger can prove to be quite potent.
 

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Well since I'm one of the few out there with a s/c I'll throw in my opinion and experiences.

I went with s/c for a few reasons. I liked the idea of being different from other FI 2.5rs out there. The install was straight forward very easy. The boost is always there, I get boost the second I hit the pedal. No messing with oil lines, etc. I like the general sound better then a turbo blow-off. Also no psi spikes which love to blow motors to kindom come. So there you go.

Now I driven a highly mod turbo rs as well, be it was an auto. It was, i believe around 300+ at the wheels. It was hp limited only by the fact the fuel injectors were maxed out already. Anyway that car was a different animal from mine. It would just hit boost and wammo your head is in the back of the seat. In my s/c it would just move whenever I hit the gas, no waiting at all. I liked the s/c feel more for the street/normal driving. It just makes the car more powerful and gives it that sweet big engine feel.

I plan on getting some hp numbers later in the sping time, just to show you what to expect from a well tuned rs with 6psi.

MadMax:checkit:
 
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Discussion Starter · #18 ·
MadMax,
Got any pics of that beast? I would love to see it!
I went with AVO Turbo set up. I have driven one of those older turbos, I know about the lag you guys are talking about. I have factory turbo cars with terrible lag too. My high compression / low boost turbo set up has no lag, boost comes on at 1500rpm , 6psi by 2300. full vacuum to full boost like an n/a car. (I am sure no one will believe me, If you are in Portland, Or. you can check it out) Now the turbo is small enough to run out of steam by 320hp(290hp now), so we can't build a monster out of this setup. Drives like a dream on the street though. No electronic boost controller to spike. No patchwork electronics that run on the edge. Just like the S/C kit Templar is building, if you do it right, it will last.
IMHO: No matter how we add boost to the RS, let's do it. Kill the WRX ! Kill the EVO ! Bring on all competitors!

Sean
 

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here is a shot of my setup. I seen your setup and kits, and though they were one of the nicest out there. I wish I could afford two RS, then i have one s/c and one turbo'd.

Lol give me your rs :biggest:

MadMax
 
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