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Leg 3.6R, FXT, XV, BRZ
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Discussion Starter #1
Hey I get the 1st post in this column award!

Why is it that my N/A car...is so much faster than the turbo cars I've run against???

Displacement baby! :D
 

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Retired Admin
Two Mini Coopers!
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10,637 Posts
You get both - if you turbo the 2.5 - which is what I think I'm going to have to do (I can't afford my 6cyl idea - oh well!) sometime next year I hope??? :D
 

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Has anyone considered ram air for the '00 2.5RS? Is the tach limit at 6200 to limit max speed or prevent valve float?:confused:
 

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RAM air doesn't help much at the lower speeds. I "used" to run a 3" dryer vent hose from the orange triangle thingy in the front bumper ( I took that out ) up to the air box. I have about a 45 mile drive home and the speed limit is 75mph for 3/4 of the way. Around 80mph is when I noticed that it started helping. After 90 to 100mph there was a noticable difference. But the threat of water in the intake was just a bit more than I wanted to deal with.

Cold air intakes do help though.

As for the 6200rpm limit, I'm not to sure. I thought that valve float started around 6500 - 7000rpms in these engines. Again I'm not sure about this.
 

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If valve float doesn't start until 7200 our red line should be at 7000...like the WRX!

Water in the intake is not usually a problem in the desert.....I will be installing water injection to bring up the humidity to a balmy 60% (from 10 to 15%) to reduce knock induced retard (with 91 octane fuel on a hot summer day my performance suffers!)

Ram air with the right filter media and air box design would aerosolize most incoming water and the excess would drain away through the flood vent. Besides a cold air intake drawing from the fender well tends to get road spray!!!:cool:
 

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i ran my 00 RS with a open hood scoop with a HKS megaflow where the stock filter used to be during the summer. throttle response seems alot better, and car seems to be smoother. acc. faster too, and a lot louder. makes a huge difference on the freeway.

jansen
 

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Carless......sigh
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153 Posts
regarding the red-line. Usually motors will turn far more revolutions than are indicated on the tachometer. This is because the other components such as alternator, a/c pump, or power steering pump cannot turn as many revs as the crack can. Ram air? You can not generate enough compression while tooling around town to make any difference. I would just super charge your motor. ;-)

Michael Olds
Da Lufty
 

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13 Years of RS
2005 Toyota Corolla :(
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5,537 Posts
Mmmm, supercharger...:drool: Anyone know who makes a reliable SC kit for the 2.5L engine? I would much rather go SC than turbo, but there aren't many options for SC's. That, and I still have 3 years on my warrenty, so I have plenty of time to find something!
 

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Yeah, a SC would be sooo nice!!! I need to start saving 'cause I'm outrunning my warranty!!!

Speaking of redlines, how do you go about increasing them?? An extra few hundred rpm would be really helpful. I'm guessing there's no "magic screw" to turn!

Oh, NA rules b/c turbo lag sucks!

-Mike
 

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'05 LGT / '06 STi
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A group called DNT performance is working on a kit currently. The test car is a 2000 RS. The fellow Templar on this board or the i-club can answer your questions, it's his car and his project! I want one for the Luxo-barge (legacy) hehe..
 

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13 Years of RS
2005 Toyota Corolla :(
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5,537 Posts
quicksilver said:
Yeah, a SC would be sooo nice!!! I need to start saving 'cause I'm outrunning my warranty!!!

Speaking of redlines, how do you go about increasing them?? An extra few hundred rpm would be really helpful. I'm guessing there's no "magic screw" to turn!

Oh, NA rules b/c turbo lag sucks!

-Mike
I think the best way to raise the redline is to get an aftermarket CPU or piggyback chip that will delete the fuel/spark cutoff, and then you will need stronger valve springs to prevent valve float. Or just get the Cobb heads with the valves, springs, and cam, then you should be pushing some power! By the way, I don't know which chip will do that for you, but I'm sure someone does!
 

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I believe Cobb had tested a set of SOHC heads and found that valve float started around 6700-6800RPM, and that at the stock redline it would start at about 10psi (due to all the pressure on the backside of the valves). Oh wait, this is NA... oh well, no harm in additional info. :p
 

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Dave G said:
Has anyone considered ram air for the '00 2.5RS? Is the tach limit at 6200 to limit max speed or prevent valve float?:confused:
i think it's due partly becuase the power band on a RS drops severely after 5500 rpms. once turboed though, it can pull all the way to 7k no problem.
 
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