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-   -   Supercharging? (http://legacygt.com/forums/showthread.php?t=173646)

Flyboy888 11-03-2011 04:18 PM

Supercharging?
 
Anyone thought of it? I hear the ej251 doesn't do too bad with stock boost (8psi) one turbocharging is a bit complicated, so has anyone thought of supercharging?

BrandonJ 2001 GT Limited 11-03-2011 04:38 PM

Supercharging would require as much as a turbo in a way. You have to find somewhere to run a belt off the crank to the SC, then still run an IC and piping. You'd still need a piggyback controller to map the injector and fuel changes. Upgrade fuel pump especially if you think you can run 8psi.

Turbo kits for the 00-04 Leggy only run 5-6 psi.

Either one is a recipe for failure if not done right. And it sounds like if you want to run 8psi on stock EJ251 internals...be prepared to set aside $4k for another engine. We dont have Civics.

SurlyOldManMN 11-03-2011 05:10 PM

I don't think it's going to be any different. I would expect supercharging to be more complicated if anything. You already have exhaust to smack the hot side of a turbo, you don't already have a convenient pully just sitting around waiting to tie the crank shaft to a supercharger.

The rest of it is basic forced induction. Six of one/half dozen of the other.

Flyboy888 11-03-2011 05:33 PM

Quote:

Originally Posted by BrandonJ 2001 GT Limited (Post 3620515)
Turbo kits for the 00-04 Leggy only run 5-6 psi.

So wait they actually make kits for our cars??? and 5-6psi being "safer" than 8psi, wouldn't you need to get another exhaust manifold? to mount the turbo too

Flyboy888 11-03-2011 05:36 PM

If i did any forced induction, id prefer to do turbo, but my assumsion was always that it would be more difficult. But if not i might look into a kit. Any links?

L_C99 11-03-2011 05:42 PM

The only way supercharging is easier is because you don't have to mess with exhaust. That is it.
The only kit that comes to my mind is the AVO turbo kit, though there may be others.
http://www.avoturboworld.com/avoshop...25-c-1_87.html

wolflegacy 11-03-2011 05:59 PM

the process itself is relatively the same for both
the only difference would be that a supercharger is a lot safer than a turbo on na cars because you don't have the risk of detonation
on a turbo a boos spike is more common and it could blow your engine up but the supercharger is fizically attached to the crank there for it eliminates all the chances
i say supercharge it if you want to keep the stock internals or upgrade internals and get a turbo
i am also looking in to supercharging next year
the eaton m62 of the c230 merc is the best fit for out cars and it doesn't require inter cooler for that low boost

01rs25 11-03-2011 06:41 PM

You guys looking to add forced induction to your 3rd gens will get gobs of info over on RS25.com.

All RS' used some sort of SOHC/ DOHC configuration that the majority of you guys are looking to boost. Check the Forced induction forums. Skidd has a step by step guide with pictures on how to supercharge an N/A 2.5.

BrandonJ 2001 GT Limited 11-03-2011 09:34 PM

I was thinking of the AVO kit....It's something like $4500. BUT...if you can grab a stock TD-04 and swap in a MBC to regulate @ 5-6 psi, stock WRX manifold, up-pipe, down-pipe, notch your own crossmember, E-Bay FMIC, and tap your own oil and water lines...then add a 5th injector and PP6 or SMT-8 piggyback controller...you could get away for $500-1000 at best. There's a 4th gen with the AVO kit pushing about 6psi laying down numbers similar or better than a stock GT.

***Currently putting down 201whp at around 5750rpm. The torque curve is not completely smooth so there are 2 peaks. First peak is at 3550rpm with around 195wtq and at about 4400 rpm it is 205wtq.

I'm running about 6psi, my tuner said it goes up to 6.2. ****



and...I thought all forced induction had a risk of detonation if you werent tuned right.

Flyboy888 11-04-2011 02:28 AM

What would the 5th injector be for?

Flyboy888 11-04-2011 02:32 AM

Quote:

Originally Posted by wolflegacy (Post 3620609)
i am also looking in to supercharging next year
the eaton m62 of the c230 merc is the best fit for out cars and it doesn't require inter cooler for that low boost

I was thinking the m62 as well or the one from the older grand prix GTP. I believe its the m90? Not sure tho.

itsme 11-04-2011 02:40 AM

[QUOTE=BrandonJ



and...I thought all forced induction had a risk of detonation if you werent tuned right.[/QUOTE]
They do. The motor doesn't care how the air is compressed. You can have the same problems either way when it comes to knock.

BrandonJ 2001 GT Limited 11-04-2011 07:57 AM

Quote:

Originally Posted by Flyboy888 (Post 3620979)
What would the 5th injector be for?


So you dont go lean under boost. The PP6 and SMT-8 have an output that fires a 5th injector when it needs it.

BAC5.2 11-04-2011 08:01 AM

Quote:

Originally Posted by wolflegacy (Post 3620609)
the only difference would be that a supercharger is a lot safer than a turbo on na cars because you don't have the risk of detonation
on a turbo a boos spike is more common and it could blow your engine up but the supercharger is fizically attached to the crank there for it eliminates all the chances

This is stupid. Why would someone thank this post?

Don't let your boos spike!

BrandonJ 2001 GT Limited 11-04-2011 08:07 AM

Another thing I just thought about. Both the Cooper S and Cobalt SS started with superchargers and went to a turbo in the later years and current models. IMO, if the SC is/was a great idea on a 4cyl....why didn't those two cars stay SC?


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