Do you even KNOW what a Rotary engine is??? It does NOT use cylinders/rod to make power. Please go check out some info before you speaks. And do you have any prove that I4 makes more power then F4? I believe the STi 7 make more TQ then EVO 7. And the S202 STi was rated the most powerful 2.0L engine in Japan. Moreover, if the "I" configuration is so great, how come Porsche and Ferrari use "V" and "F"?

 

Not really a clean comparison.
Ferrari uses primarily large displacement engines and 8-cylinder configurations.
At present, Porsche primarily uses the 3.6l Boxer 6, which is frankly much larger than the STi and EVO displacements.
Also, Porsche licensed 's balance shaft design for it's own engines
The Subie 2.5l has displacement advantages and the 4G63 is true and tested. New versus seasoned.
Only time will tell who wil rule.

 

i know what a rotary is...in fact, here's my friend's old FD RX-7 with my WRX...what i'm saying is you are making the blanket statement that displacement always can produce more power and that's simply not true...yes, it's a different engine design...just like an inline, a flat, and a V are all different engine designs...each with their own benefits

an inline can simply withstand more boost than a flat because of its design

the 2.5L STi may produce more power than the 4G63...i don't deny it's possible...what i am saying, what people like you don't seem to understand, is that displacement doesn't always equal more power and you can't argue the power or capabilities of a non-existant engine (i.e. the 2.5L STi that has never been made before)

you have made the exception that engine design does, in fact, make a difference when it comes to producing power...different designs each have different positives and negatives...for example, the W-16 in the new Bugatti is a W for one main reason, so it fits in a smaller physical space...an inline or V-16 design is certainly possible, but those engines would be huge...a W-16 fits in the space of a V-12

the S202 was a very limited production car...it may very well be the most powerful stock 2.0L in Japan...but that's stock, not modified

 

I will buy the Evolution because I can buy it in a few days
My girl friend needs a new car. I talked her into waiting until June.
Now I have to convince her she needs an STI.

 

You still have no prove that an inline can simply withstand more boost than a flat because of its design!!!

I m not saying Displacement is always the answer for power, but in this case, both EVO's and STi's engine are highly tuned, so the 500cc extra displacement will help the STi to make more "relax" HP and more high end power. The 2.5 engine is just a EJ20 with a stroker kit. Everything else is the same, and Japan is planing to put that 2.5T engine in the new Legacy.

I know both of these engines are great, but what if make a 2.5L EVO, will you have any doubt?

 

Ok......first about the engine arguement......
Inline 4's have had more development than Flat 4's so the 4G63 has the upperhand in making more power. The USDM STi's engine is untested but I'm sure that it's a strong engine capable of producing the same amount or more modified power than the 4G63. If this wasn't the case, Subaru wouldn't be using this engine in many of the upcoming cars from Subaru.

Second......what would I pick??
WRX STi
Pros
2.5L Boxer w/ 300HP and 300TQ
Weight (rumored to be a little over Spec C or about 3000lbs.)
Strong 6SPD Transmission from JDM STi
DCCD
Exterior/Interior design
Cons
New engine
Might not handle as well as the EVO
DCCD (mechanical diffs can be just as good)
Weight (still to be released)

EVO VIII
Pros
Proven engine
Twin - scroll turbo (less lag)
Good handling (mechanical diffs can be better)
FMIC (not heat soak)
Nicely geared 5SPD MT Transmission
Cons
Exterior/Interior design (the front looks like a ****ing Pontiac and the ****ing retarded Altezzas and the interior can be better)
The weight (no electronic diffs yet still gains 200 extra pounds)
Questionable power claims from Mistu as seen in Shiv's post
Official Sponsor of 2 Fast 2 Furious (rIcE bOi appeal)

Winner?????????????
WRX STi.......by a SLIGHT margin

 

Less lag? Even with the 2.5L? Er?

-bd

 

the advantage inline engines have in turbo charging is that they can have a strong iron block and weigh less then a "flat" or "v" engine. They are also more efficent in that the the headers coming out of the exhaust ports are all in a nice little line - this makes using a single trubo much easier.

BUT, flat engines have a great low center of gravity, which is why Porsche & Subaru use them in their race cars (and both have been damn successful with them)

 

You shouldn't really make those assumptions yet. The STi still hasn't come out. The only way to find out which one is better is to have an unbiased magazine do a shootout between the two.

The EVO might handle better or it might not because the STi had it front geometry changed to take out understeer. The EVO and the STi are about the same in braking. They both use Brembo 4 - pot front clapiers with 13 inch rotors and Brembo 2 - pot calipers with near 13 inch rotors in the rear. The tires on both cars are equally as sticky too. Braking also depends on vehicle weight, so far the rumors say that the USDM STi will be at 3000lbs when it arrives making it lighter than the EVO by about 200lbs. I doubt the 200lbs. would make that much of a difference in the incredible braking that these two cars have, it's at most a difference of a foot or two.

Lag won't be much of an issue with a 2.5L until a much larger turbo is installed. The turbo on the 2.5L STi engine is an IHI VF34 which was used in the 2002 JDM Sti Type RA Spec C. The VF34 is the ball bearing version of the VF30 which is one of the fastest spooling turbos for a Subaru (full boost at 3800rpm) and with the ball bearings, the VF34 spools faster than the VF30. The VF34 is capable of making +350HP on the 2.0L WRX engine with the proper modifications and operating at its max boost rating. It should be able to make more power on the 2.5L STi engine with room left to spare and without the lag of a larger turbo. It's a pity that the USDM STi doesn't get a twin - scroll unit like the JDM version though.

The reason that the 4G63 is capable of making more power than the 2.0L WRX engine is that Inline 4's have have more time and money invested in it's development. The Inline 4 has been in existance longer than the Flat 4. If the Flat 4 has been around the same amount of time and has had the same amount of money invested into it, it would make the almost the same amount of power as an Inline 4.

 

Not all I4 engines use iron blocks. Don't make assumptions based off the Evo. Also, there is not proof that I4 engines weigh less than a flat 4. Where are you getting your info?!!

You are correct on the header design and the low cg fact tidbit, but don't go assuming things w/o evidence.

The Evo engine is a super strong engine. I personally think that both engines will make about the same amount of power. I think the Evo's has some really good internals and an iron block that they have been using for over 10 years. I think the STi will be able to produce more power initially, but with its all aluminum construction I wonder how high the boost can be turned up and held that high over the miles.

Both are fantastic cars and I wouldn't turn my nose up at either. People need to stop hating on one car over the other. The Evo and STi may be competition, but that doesn't mean the Evo owner has to hate the STi owner, etc. That's junior high.

 

I never said all I4 engines use iron blocks - but most turbo-charged engines do (or a use a thick iron cylinder wall liner - and this is regardless of the number of cylinder or engine configuration). This is because iron handles the added stress better then their aluminum. And yes, if you have 2 similarly displaced engines, one in an in-line configuration, and other in a flat configuration - the in-line will weigh less (all things being equal). Esample: you only need 1 set of camshafts (among other pieces of associated hardware), and you can share more of the physical block material between cylinders. These two factors (and I am probably missing some) more then make up for the longer crank that adds weight to the in-line configuration.

I am not bashing the STi, never have, never will - read my posts. I fully realize the Evo wouldn't have come to the US without the huge success of the WRX. And I am very glad the STi is coming, the sooner the better. My main ***** is that we aren't getting a hot EJ20 or 22B in the STi. I will take known reliability and a rich racing & tuning history every day of the week in a car like the STi/Evo. The 2.5L subu engine has neither the rally-bred pedigree nor huge known tuning capacity of the EJ20 or 22b. I want to see tuned STis & Evos on the track ASAP (think streets of willow springs!), and the development of parts for the US only spec 2.5L STi is going to lag behind… ...

And I don’t hate any car, or anyone because they own a specific car. Fact is, I really don’t hate anyone (and certainly any car). I like performance cars, and I don’t care where they are made, a good performance car is a good performance car…. I just wish we were getting the J-Spec STi, the US spec may be as good, or better, but losing the 2.0L flat4 is a mistake and gets away from the rally-bred heritage that makes these cars so cool. I felt the same way when Ford introduced the 4.6 SOHC & DOHC engines in the Mustang. Granted, these are pretty good engines, but to go away from the 5.0 was just sacrilege and spit in the face of more then 25 years of racing heritage.

Just my 2 cents….

 

One great benifit of a flat engine is the extremely short crankshaft. Less room for flex, can handle large amounts of power. About the only times I've heard of Subaru crank failure involved lost oil pressure.

The top mount intercooler is not quite as effective as a front mount, but it's not bad. When the car is at speed it will have a nice flow of air across it. It's actually sitting above the tranny, and has some space below it. Remember, a FMIC is also sitting right next to a large heat source, the radiator and condenser. So it's possible for it to heat soak as well when it doesn't have a good flow of air(stopped, low speeds, etc).

 

trigeek,
I know I wasn't addressing my reply just to you..only the first part of it. I had read into your statement as a generalization since you said "the advantage inline engines have..." I read plural engines, or more than the 4G63. No worries either way as I certainly wasn't trying to instigate anything with you nor anyone on this forum.

Very true, that and a TMIC has less plumbing to go through and less pressure drop. On a heavily modified turbocharged car the only way to go is FMIC. On a mean street machine like the STi..the TMIC works great.

 

The 22B is a car not an engine

-bd

 

I have always heard Subu's 2.2L high performance flat4 refered to as simply the 22b, for both the car model and the engine code. I am probably wrong... what's the correct engine code?