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Old 12-10-2002, 09:03 PM   #1
Scooby Newbie
Member#: 11679
Join Date: Oct 2001
Location: Chi-Town
Default Fast 2.5 rs N.A?!

hello, im thinking i might stick to na. So are tehre any build fast na 2.5rs's? What mods would i have to do to get a fast as hell na 2.5 rs. Able to smoke alot of cars? Thanks
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Old 12-10-2002, 10:06 PM   #2
Scooby Guru
Member#: 22452
Join Date: Aug 2002
Chapter/Region: MWSOC
Location: Grand Rapids, MI
2016 WRX


Sounds like you need naaaawsssss.
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Old 12-10-2002, 10:37 PM   #3
Scooby Guru
Member#: 6637
Join Date: May 2001
Chapter/Region: MAIC
Location: Manassas
2009 Acura MDX Sport


rs= really slow

smoke alot of other? smoke your motor....

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Old 12-11-2002, 01:34 AM   #4
Scooby Specialist
Member#: 3149
Join Date: Dec 2000
Location: montreal quebec
01 V7 GC/R32 sky


Hey man, good to see someone else wanting to stick to n/a! Ill give you alist of my mods so you can see what you might want to look at and research:

Strommung cat back
randon tec hi flow cat
borla headers
Cobb intake
Lightend UD pulley
custom ported and polished intake manifold
custom ported and polished cylinder heads
Cobb's most aggressive n/a cams
Cobb valve springs
Cobb titanium retainers
custom valves
closed deck block
sleeved block
knife edged crankshaft
11:1 compression custom pistons (coated for nitrous use)
custom connecting rods (increased rod ratio +4mm)
(The whole engine will be balanced and blueprinted)
Upgraded fuel pump
ACT street clutch
Lightend flywheel (switching from a 14 lb to a 9 lb flywheel)
STi tranny mounts
STi engine mounts
Unichip engine management
Nitrous Express wet kit direct port 55 shot
Redline set at 8,000 rpm

My block is finished, we are waiting for the pistons and rods to come in, so Ill have my car back by xmas. tattoo collector is also going with an 11:1 compression engine. I am hoping for a 250+ crank hp from this (maybe 300 with nitrous), but a new intake manifold will help this, it is the biggest restriction.

Its a lot of work, but start with the basics and work you way up from there. This took me 2 years and a few set backs from using the wrong nitrous kit when i had my heads and cams (dont use a dry kit, go safe with a wet).

Youll find everyone really helpful on this and there is a lot of info out there too so far. Good Luck!


Last edited by dcoty; 12-11-2002 at 01:12 PM.
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Old 12-11-2002, 11:11 AM   #5
Scooby Newbie
Member#: 12526
Join Date: Nov 2001
Chapter/Region: Tri-State
Location: Northern NJ
04 rex
MY04 bjm rex wagon


i peronsally like the NA approach..BUT it is really expensive ....better to use a forced approach...and the work involved in a NA build up is crazy
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Old 12-11-2002, 01:42 PM   #6
NASIOC Supporter
Member#: 232
Join Date: Sep 1999
Chapter/Region: MWSOC
Location: Ft Wayne, IN
02 Forster-S


dcoty's got the right recipe but even I, the N/A stalwart, have decided to go turbo. Everything I built into my N/A build was with that possibility in mind (street -vs- spicey cams, header design, etc). So far, my turbo setup goal is under $1k complete and so far we're way below that. There's no way to get the 40-ish more hp NA for that kind of money. Listen to dcoty, he's definately on the right track.
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Old 12-11-2002, 01:56 PM   #7
Scooby Specialist
Member#: 3149
Join Date: Dec 2000
Location: montreal quebec
01 V7 GC/R32 sky


Thanks BOY!

Turbo sounds very nice to me, I would love to have a turbocharged car, honestly, but I really wanted to do something reletivly different, it took a long time to decide what I should do. In the beginning I bought street cams because I diddnt know what I was going to do, but I eventually thought I should sick to N/A. I absolutely love driving turbo cars, they are tons of fun! Im curious to see what mine will drive like when i get it back.

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Old 12-11-2002, 09:45 PM   #8
Kevin Thomas
Street Racing Instructor
Member#: 110
Join Date: Jul 1999
Location: 1997 OBS, 1996 SVX, 1988 RX
1989 1989 XT6

Default Ahh

Originally posted by dcoty
Thanks BOY!
Im curious to see what mine will drive like when i get it back.

I'm curious as well! People have always been talking about this for years now and besides Andres, you seem to be building a really go fast N/A RS. I can't wait to see how it runs myself. Good luck with it all. That is one car I would love to own. Too many turbo'd RSs out there now.
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Old 12-11-2002, 10:06 PM   #9
NASIOC Supporter
Member#: 7022
Join Date: May 2001
heh, DC ITCA are
my rides


not to hijack, but dcoty: Why unichip? I think that is going to be your biggest weakest link. A haltech, tec 3 would be worlds better because of how well you can tune with those ECUs. Alot more control initially and untill the car is running well.

back to the subject: if your thinking of sticking N/A with n2o be safe and go wet. I have seen many people on this club loose a motor because of the dry stuff.

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Old 12-11-2002, 10:13 PM   #10
Patrick L
Scooby Specialist
Member#: 634
Join Date: Dec 1999
Chapter/Region: TXIC
Location: Tulsa, OK
2000 Impreza 2.5RS
Becasue ITS racecar


Don't forget, your going to need some stronger gears. I broke 2nd gear in my stock tranny running a ACT clutch, stock engine, cranck pulley with intake and catback exhaust.
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Old 12-12-2002, 02:45 AM   #11
Scooby Specialist
Member#: 3149
Join Date: Dec 2000
Location: montreal quebec
01 V7 GC/R32 sky


Definitly go with a wet kit, I broke a valve using a zex dry (55 shot) kit with heads, cams etc. 3 spark plugs melted, and my fuel injector got stuck open, broke a valve. i got that fixed and when i went to tune the Unichip, i raised the redline to 7,000 rpm (i had springs and retainers to handle that) anyway, we guessed that there was some residual damage and I spun a bearing and got rodknock.

Doctor Nick: I absolutly agree with you on that, but I wasnt sure how much further I was going to go when i got the uni installed, but when i spun a bearing i decided to go all out. The unichip now is our one worry as to weather it will allow for enough corrections to get my car running right.

Top_Dog: Thats too bad with the tranny! How much did that set you back if I can ask? I will definitly have to get to this problem eventually (after I destroy it at the 1/4 track of course!).

Does anyone know what andreas has done to his bottom end? im really surious cuz I really want to see what Im up against, I guess I have to beat a 14.3 1/4 mile or something wthout nitrous to do that.


If anyone comes to montreal, thay get a ride!
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