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Discussion Starter · #1 ·
I just traded my supercharged civic for a 2003 WRX. Now I need to know the best approach for getting the hp to hold on until redline. I am hoping that the solution is in an electronic boost controller and exhaust. I really don't want to get into felony cat removal because I live in Atalnta where they do get a little tough. What is the latest info?

Thanks
 

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Thinking Man's Engine
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Don't you mean a flat torque curve?

Though I think you mean a linear hp curve all the way up to 7k.

Below 3000 rpm...it's not as feasible, unless you resort to a smaller turbo or smaller A/F ratio, or shell you big bucks for the ball bearing turbo that has some magical friction reducing grease.

A lot of people go for a MBC....for EBC...Sport Compact Car did a comparison of EBC's in the July 02 issue, though that was with an internal wastegate. Not sure when they did a follow up review with external wastegates.
 

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You can get a new actuator from AVO...that will hold boost until redline...then you will probably want to get a ebc for greater control...

As far as the exaust goes they don't test in Fl anymore. But I would think you could get by with one cat in the downpipe...you may want to check that out before you do it...if you can you will get a nice bump in hp by eliminating the other two and a huge improvement in drivability without the corked up uppipe
 

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Agreed. The TD04 can't cut it past 5500 rpm. My hybrid, however, will keep pumping all the way to the redline. Any of the upgrades will help the top end. But some will add some lag, so figure out what you want and choose the right turbo for your driving style.

BTW, I still have all cats in place. If you choose to keep them, you're going to have to limit your goals, but adjusting the power curve is easily acheived and makes a big difference in driving pleasure. My personal goal is about 280 hp at the crank, but my real goal in increased torque for better drivability. So far, I've been able to get a good increase with just this turbo, even on stock boost and using the stock ECU.
 

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I'm with, tan. I like a nice slope on HP, but flat torque is pretty nice. Id go VF30 at 15psi on open exhaust. You can upgrade to bigger injectors, pump, and get an ECU later and crank it up to 17-18psi and see even more gains. The VF30 is an excellent all around turbo for the EJ20, IMO.

If I can help with anything else, feel free to email me.

-Jim
 

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Discussion Starter · #8 ·
Thanks for the replies. Ok, if it needs to be a bigger turbo, which one should I look for? I don't want any more lag. Is there a ball bearing turbo that will spool as fast as the stock one yet still give me a little more top end? What about if I use an electronic boost controller, will that allow the turbo to spool sooner? Forgive my questions but I am new to turbos. I have lots of experience with my supercharged honda. I started with an intake and cat-back and went all the way through a supercharger + nitrous + Haltech E6K. The one thing I have learned is to make damn sure that a product does exactly what I want before spending a penny. I took a big loss on those parts on eBay and I am still selling some of it. Here is the nitrous...

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=1871364833&ssPageName=ADME:B:LC:MT:1
 

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>Thanks for the replies. Ok, if it needs to be a bigger turbo, which one should I look for? I don't want any more lag. Is there a ball bearing turbo that will spool as fast as the stock one yet still give me a little more top end? What about if I use an electronic boost controller, will that allow the turbo to spool sooner?

No there won't be one that has less lag that is for sure. If you want bigger, guess what, you'll have more lag. This question gets asked constantly yet I'm not sure why as you can't really break the law of physics. The ball bearing will help with spool up yes but not to the point of that instant lag free response of the stock unit. Now removing the cats while going with a small upgrade like a VF29 will yield some excellent spool up especially if tuned with a piggyback or standalone ECU. I think that's your best bet and you still have the stock unit to put back on if you want to sell the car. They're only $800 which is just a bit more than people charge to upgrade your stock unit. Yes, an EBC will definately help with lag on any turbo.
 

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Adding an EBC and going catless with a VF34 should be about the same lag as stock (maybe even a little better:) ), but will make MUCH more power. Going with something even smaller than a VF34, like a VF24-29 or an OE upgrade, should definately put you under the stock levels of lag, but with noticably more power on tap. I guess the idea is, get the EBC and go catless with an uppipe and good turboback exhuast, and then decide how much lag (and how much power) you want to add.
 

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Discussion Starter · #11 ·
It looks like the best thing for me to do first is get the EBC. If I go ahead and get the downpipe now, then get a new turbo, isn't there a risk that the new turbo won't fit the downpipe? It seems that there are different configurations depending on your turbo outlet porting. I got burned really bad on the Honda when I bought things that got replaced later on, such as when I got a Field VTEC controller, then an EFI Systems PMS, then a Haltech E6K. I want to make sure that I focus on a goal, and carefully select components that work together to get me there.
 

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TurboXS stage 2 vs. stock:



a much better curve, but it still doesn't hold all the way to 7k, any better than that and you're looking at a new turbo..

how much $$ were you wanting to spend?
 

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recursian said:
It looks like the best thing for me to do first is get the EBC. If I go ahead and get the downpipe now, then get a new turbo, isn't there a risk that the new turbo won't fit the downpipe? It seems that there are different configurations depending on your turbo outlet porting. I got burned really bad on the Honda when I bought things that got replaced later on, such as when I got a Field VTEC controller, then an EFI Systems PMS, then a Haltech E6K. I want to make sure that I focus on a goal, and carefully select components that work together to get me there.
Yes uppipe/downpipe and an EBC is your way to go first. The downpipes should fit all the mild turbo upgrades no problem. The EBC is always useful so that's also a good investment.
 

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Re: Re: need flat hp curve all the way to 7k

God said:
Yes uppipe/downpipe and an EBC is your way to go first. The downpipes should fit all the mild turbo upgrades no problem. The EBC is always useful so that's also a good investment.
Shockingly, God and I are in agreement, but I ALWAYS remind people of the $40 Joe P MBC option as well. (Don't worry Dan, I'm starting to ome around to the EBC since I went to my VF30.)

-Jim
 

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Discussion Starter · #15 ·
The more I read about it, the more I think that an SR 40 or PE 1820 turbo upgrade is going to be the ultimate solution. I assume that the TurboXS downpipe will mate with that turbo. I think with an EBC, up-pipe, TurboXS stealth-back, Prodrive rear section, Unichip or UTEC, the power would be awesome and still have acceptable lag. We're talking some serious costs though. I thought it would be a little easier than that.
 

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recursian said:
The more I read about it, the more I think that an SR 40 or PE 1820 turbo upgrade is going to be the ultimate solution. I assume that the TurboXS downpipe will mate with that turbo. I think with an EBC, up-pipe, TurboXS stealth-back, Prodrive rear section, Unichip or UTEC, the power would be awesome and still have acceptable lag. We're talking some serious costs though. I thought it would be a little easier than that.
your top end will be great, but if you were concerned with lag, i would stay away from the PE series. the VF-35 basically spools the same as the stocker (TD-04) however offers boost through redline of 16psi+.

dR
 

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and of course, there is always the tuning side of things, which is one fo the biggest manipulators of spool time out there.....

just to add fuel to the fire :)

Adam
www.z1auto.com
 

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Discussion Starter · #20 ·
Are you suggesting that I could control spool by adjusting the fuel and timing to get more heat in the exhaust? On my Honda (the H word again), I found that retarded timing would get things really hot. I suppose you could set up the low RPM - high load area of the maps to get things going and then adjust to get best power in the areas that the boost is higher. Is this what you mean?

Thanks
 
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