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Discussion Starter #1
1) How come the GS300 has 5HP more then the IS300 with the same engines? Is it because of the exhuast system?

2) Why is the MPG so bad? Could it be the gearing?

3) Why use VVT-i and not a VVTL-i? Does VVTL-i just not exist for a 3.0L engine?

4) Does the engine have good NA potentials? I've seen the Celica run 14.8et with only intake and exhuast. Sure the IS300 weighs more but also it has a bigger engine.

5) Whats the theoretical max horsepower I can obtain from this engine NA with the car(manual version) still being street legal?

I love this car although it has some drawbacks but I'm sure there'll be ways to work around it. What gets me the most is my Prelude still's faster and sometimes it gives me that sense of "going down a step" but hopefully not for long.
 

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Originally posted by LexusIS886:
1) How come the GS300 has 5HP more then the IS300 with the same engines? Is it because of the exhuast system?
I'd say that's prolly it, and I'm sure the all the "air flow" elements of the car are slightly different, which could all contribute to the 5hp


5) Whats the theoretical max horsepower I can obtain from this engine NA with the car(manual version) still being street legal?
This isn't really a question about street legallity, but more about how much $ you have to throw into the car. You can basically rebuild the car from the ground up and still have a street legal IS300, albeit w/ 700+hp... the guy on here w/ the sick 700hp sc400 could tell you that. But hten again, you're asking about NA, so it's hard to say... I'd say that the IS300's that raced in the motorla cup are a good example of what I'm talking about. Does anyone have any dyno info on those cars?

Originally posted by LexusIS886:
What gets me the most is my Prelude still's faster and sometimes it gives me that sense of "going down a step" but hopefully not for long.
The prelude isn't even the same kind of car... apples -n- oranges.

[ April 24, 2001: Message edited by: s0yb0mb ]
 

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Discussion Starter #3
I have say $4k to spend but I just don't think I'd want all the hassles of having a turbo dropped in.

I agree that comparing the Prelude and IS are like comparing apples and oranges but I still wanna go fast as one, hehe.
 

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There all sorts of tweaks you could do to the car - intake, exhaust, torque converter, AFC - that can add speed without going the FI route.

Just a thing to think about before you add a lot of power to the car (not that I think you're going to get a lot more out of it without FI) is that while the brakes are real good for the stock, if you start really boosting the output of the engine, you'll want to upgarde the brakes first, so that you don't find yourself unable to stop in time after racing to that stoplight.
 

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VVTL-i currently exists only on the 2ZZ-GE engine. Personally, I'd rather have Toyota develop Dual VVT-i (currently on the 3S-GE that powers the Altezza RS200, which is NOT turbo'd, you nuggets) on its larger engines (6+ cylinders). BMW uses Double VANOS (same concept as Dual VVT-i) in most, if not all, of its gasoline engines (dunno about the diesels, however), and look how much power the E46 M3 has...
 

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Originally posted by JW:
VVTL-i currently exists only on the 2ZZ-GE engine. Personally, I'd rather have Toyota develop Dual VVT-i (currently on the 3S-GE that powers the Altezza RS200, which is NOT turbo'd, you nuggets) on its larger engines (6+ cylinders). BMW uses Double VANOS (same concept as Dual VVT-i) in most, if not all, of its gasoline engines (dunno about the diesels, however), and look how much power the E46 M3 has...
you are one of the few ppl who doesn't think that the altezza comes factory turboed...
 

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Originally posted by LexusIS886:
1) How come the GS300 has 5HP more then the IS300 with the same engines? Is it because of the exhuast system?

its down 10hp actually, and i would say that it is attributed much more to the design of the exhaust manifold, rather than the single vs dual exhaust thing.

2) Why is the MPG so bad? Could it be the gearing?

i don't think it is actually as bad as they rate it, if you notice they rate it the same as the GS300, which weighs more etc etc, i think it is actually slightly better because the car weighs 300 pounds less than the GS.


3) Why use VVT-i and not a VVTL-i? Does VVTL-i just not exist for a 3.0L engine?

no, it doesn't exist yet, you have to remember that the motor also comes with a turbo charged version still in japan, which makes adding things like variable valve lift much more complicated than putting it in a n/a engine, it is probably still in R&D.


4) Does the engine have good NA potentials? I've seen the Celica run 14.8et with only intake and exhuast. Sure the IS300 weighs more but also it has a bigger engine.

the 5 speed IS will probably run 14.9 or 14.8 ets stock, so give it some credit. with intake and exhaust, it will probably run 14.50's.


5) Whats the theoretical max horsepower I can obtain from this engine NA with the car(manual version) still being street legal?
this question is impossible to answer, but you could squeeze atleast 300hp out of it with enough money into, in a normally aspirated version.
 

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I think I need to spread the gospel that the Altezza RS200 is NOT turbo'd from the factory.

Check my sig now...

Originally posted by HIBBoyScott:
you are one of the few ppl who doesn't think that the altezza comes factory turboed...
 
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