ProjectPhantom

u prelude owners supercharge ur car or turbo it? if ya havent done either one what would ya like to have? or just keep it n/a? i was thinkin of doin it to my car... greedy turbo or jackson super

PWMAN

Jackson SC's suck. Either a centrifical supercharger or a turbo will be even better. Turbos always produce more torque.

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88' Dodge Shadow- 2.2L, 5 speed...a couple mods
12.37@111.75 MPH

nicotine251

i got a fmax turbo kit for my 01 prelude....its pretty cool, make sure you have a engine management system for the tuning!!!!

eckoman_pdx

Roots blowers like JS supercharger are ineffiecent, and can only run very minor boost, like 4psi, without buying their upgrades...

A cyntrifugal sc is basically the compressor part of a turbo driven by a step-up gear drive (or something similer) that is driven by a shaft. The amount of boost is directly proptional to the engine rpm, with the HP and Torque peaking @ redline. This is done to prevent compressor surge. In a turbo, which is exhaust driven, when the proper psi level is reached, the exhaust gases by-pass the turbo into the downpipe to prevent it from spinning any faster and stuffering compressor surge...this is how your turbo will say at, say, 8psi from 6200 rpm until redline and not contuine to have the boost level rise. In a cyntrifugal sc, there are no exhuast gases spinning the turbine...the shaft connected tot he crack spins the compressor. You can't disconect the shaft for the crank, gear box or belt drive once max boost is reached...this means is peak boost was achived eariler in the rpm band, the boost level would contuine to "surge" or raise. By having the boost peak @ redline, this dangerous problem is overted. However, the end result is lower torque numbers than a turbo, until peak boost at redline. This also results in significant "boost lag" (you know it better as "turbo lag." Boost lag is a better term, since is refers to the lag time that can exsist until the noticable on-set of bost occurs). A Cyntrifugal SC tends to be very laggy, with noticable boost on-set no occuring until you are a ways into the rpm band. The the peak HP numbers can be good, but this power isn't really available until farther into the RPM band.

A turbo on low boost will give you good power and torque. Moreover, running a small turbo and you properly size the turbo, you can significantly decrease or eliminate noticable boost lag. Turbo sizing can effect the response of the turbo greatly, so it is important to size the turbo properly for the app. In this case, a good small turbo should get you to an 6-8psi level safe for your motor, without much noticabe lag. It should also produce good HP and torque numbers, which are much lower in the RPM band (meaning much more usable) than the Power numbers from a Cyntrifugal SC, where they occur @ redline.

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Empty Pockets Racing Member #6
EPR Member 4 Life

Polygon

I don't own a Prelude, but I can't stand super-chargers. They are far too parasitic. Turbo-chargers are much more efficient and make power from lost power.

Turbo all the way.

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Hypsi87

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Grand National. Going fast with class.
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Member ofA.A.N.B.C- Afer against non boosted crews #2

eckoman_pdx

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Empty Pockets Racing Member #6
EPR Member 4 Life

PWMAN

Sorry Polygon but I must argue. Even though I'm for a turbo, centrifical SC's are much more advanced now. The belt drive losses are about as equal to the loss you get from a turbine housing restriction. But the reason I am for turbo is because they make more low end torque and Honda's need all they can get.

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88' Dodge Shadow- 2.2L, 5 speed...a couple mods
12.37@111.75 MPH

eckoman_pdx

I agree to a certian extent. I have my issues with cyntirfugal SC's, but they arn't the ineffieceny, as they can be as effiecent as a turbo, and are often in the 70% plus range, as the vortec centirfugal SC is around 73% precent effiecent, far more eficent than a roots based postive displacement blower like Jackson Racing. That's pretty efficent for a Cyntrifugal SC tough. However, a really good turbo is still more efficent, easily over the 72-73% of a good cyntrifugal sc like votrec.

I also prefer the turbo method to create power; use wasted energy versus a supercharger, crank driven and causing parasitic losses off the crank.

It the end, a Centrifugal SC works over a very norrow RPM band, due to the nature of it's design. It basically is a compressor side of a turbo conected to a step-up gear drive (or belt drive), which is connected to a shaft connected to the crank. As you know, the gear/belt drive contrls the speed at which the compressor turns. This gear/belt drive helps a control the speed of the Cyntrifugal SC compressor. The result is it spins the compressor, no where near the optimal bost producing speed @ the low rpms. Of course, this is done to prevent the compressor form overspeeding @ higher rpms into a choke condition. As a result of all this, a cyntrifugal SC reaches peak boost levels at redline. The result is a SC with no low end torque or power, one that suffers from boost/power lag desipte being connected to a crankshaft.

I just don't see this as a very efficent way of creating power, it's certainly not the best way to go about it IMO, espeically in a honda (which can use all the low end help it can get).

I find a good, properly sized turbo to be a far better option. With the newer ball-bearing turbos, the efficency can be great and boost lag can be kept to a minumim. The result is a motor that will make power accross the board, one that will have a significaqny on-set of boost at a much lower and more usable rpm. I just find this to be the better route of the 3 options (roots blower, cyntrifugal sc, turbo).

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Empty Pockets Racing Member #6
EPR Member 4 Life

Polygon

Eckoman_pdx beat me to it.

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PWMAN

Yes I wasn't arguing to the fact that a turbo is better suited for low end power(as I specifically stated!), just to the fact that now-a-days centrifical SC's do not have a whole lot of parasitic losses like polygon said.

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88' Dodge Shadow- 2.2L, 5 speed...a couple mods
12.37@111.75 MPH

nicotine251

just to let you all know on a dyno test a jackson supercharger made more hp over a greddy turbo kit...on a prelude that is....
225hp. vs. 195hp.
so some superchargers can be better than a turbo...but its all about how much your willing to spend on your motor.

PWMAN

I'd like to see this, post a link...

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88' Dodge Shadow- 2.2L, 5 speed...a couple mods
12.37@111.75 MPH

tran_nsx

yes i would love to see this. jackson sc suck.

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PWMAN

Hah, what do you want to bet that the greddy kit was left alone and put on...while the JRSC got it's water injection kit and more boost than greddy (which is a non-intercooled kit BTW).

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88' Dodge Shadow- 2.2L, 5 speed...a couple mods
12.37@111.75 MPH