Power Of New Sti

[Smurf]

I was reading the latest Motor mag which compares the new STi to the new Evo and Clubbie.

I was really surprised by the power output of the STi. From memory it had around 157kw at the wheels. Given that this is a 2.5 litre engine and runs around 15 psi I would have expected more.

I'm never going to argue that my R33 GTST is a better or faster car though it has 151rwkw running at standard boost.

Maybe they have focused on torque. Apparently has 392Nm at the fly. Do they lose extra power at the wheels as a result of being 4wd.

What are your thoughts?

Cheers

Edited November 16, 2005 by Smurf

[Mulkers]

what is the power a the fly?

Although this is not the greatest loss of power; MOTOR's muscle car test, last year, showed the 300kw GTS only has 210kw at the wheels, and i also know that a Ford 9" diff can chew up as much as 30% more of the power as the original diff

[wrxhoon]

The 2.5 lt sti has less power than the 2.0 lt sti sold in japan and its a lot slower . The jap sti has around 240 kw at the fly and its good for 12.8 1/4 mile the model sold here and in the usa will only do 13.7 1/4 .

The subaru 2.5 lt is not a very hot engine and will not rev like the 2.0 either . Its a bit like the rb25 + rb26 .

157kw at all 4 its heaps more than 151 at the rears and no stock gtst can go near the stock sti ( any model sti that is ) .

[CONRAD]

How did the Evo go out of interest? and why does Japan continue to export watered down versions of evo's & sti's to other countries, ok maybe the US has really strict emission laws, though for Australia?

[paulr33]

15psi? are you sure

[siksII]

most regular rexes run approx 1bar even 90's models.

[Links]

http://www.autozine.org/html/Subaru/Impreza.html#US-STi

scroll down the bottom.. has some stats for Jap vs. US/Eur.

[Smurf]

The 2.5 lt sti has less power than the 2.0 lt sti sold in japan and its a lot slower . The jap sti has around 240 kw at the fly and its good for 12.8 1/4 mile the model sold here and in the usa will only do 13.7 1/4 .

The subaru 2.5 lt is not a very hot engine and will not rev like the 2.0 either . Its a bit like the rb25 + rb26 .

157kw at all 4 its heaps more than 151 at the rears and no stock gtst can go near the stock sti ( any model sti that is ) .

<{POST_SNAPBACK}>

Don't worry I realise a stock GTST cannot keep up with any STI.

Another question, how much better is the same number of kw at all 4 wheels versus the same at just the rear wheels. I undertand that there is a huge different from a standing start though once rolling, is there that much of a difference?

[Smurf]

How did the Evo go out of interest? and why does Japan continue to export watered down versions of evo's & sti's to other countries, ok maybe the US has really strict emission laws, though for Australia?

<{POST_SNAPBACK}>

The evo had marginally more power than the STI. I think it is something like 159 awkw.

Around the track they were very similar. The STI won. This can mainly be put down to the semi slick bridgestones it uses. Put the evo on the same tyres and it would have won imo.

Both ate the clubbie on the track.

[IOWNU]

How does that work though?

How can a bigger engine= slower car?

Is the car heaps heavier? The new engine crap?

I mean RB26>RB26>RB20 one would assume the same would apply to Subaru.

[siksII]

How does that work though?

How can a bigger engine= slower car?

Is the car heaps heavier?  The new engine crap?

I mean RB26>RB26>RB20 one would assume the same would apply to Subaru.

<{POST_SNAPBACK}>

the 2.5L rex is heavier than the JDM model, and yes the engine is not as tough as the 2.0L

[Maxx]

cube is cube, imo it's always better, like RB26 vs RB30

and we can't just look at the spec on paper, instead of compare the peak power, i would like to see both dyno graph, on same boost level

[scathing]

Remember, boost isn't the be-all and end-all of power. A bigger turbo will make the same power with a lower reading on a boost gauge, because its still flowing more air.

Its only useful to compare boost when comparing engines with the same turbo.

And don't forget your bolt-ons can free up power without increasing boost pressure. Imagine running a GTSt at 15psi with the exhaust and intercooler as restrictive as what the OEMs use, and then tuning the ECU to not detonate under those conditions.

Or, for a comparison to the Nissan 2.0L turbo, imagine running an S15 with the stock side-mount intercooler (maybe a slightly bigger core) and exhaust, with the only mods being a boost controller to get your 15psi + (stock is 7-8psi) and an ECU tune to stop it from detonating.

It might make the same "206kW" that the 4WD cars do, but it'd probably be just as annoyingly laggy as the Impreza's power delivery.

[TommO]

With the new STi, they have turned down the boost to compensate for the extra capacity.

scathing, I agree totally. Nothing frustrates me more than people that pull up next to a modified car they have just seen boot it, and say "hey what boost you running". Ask what turbo someone us running before what boost they are running !!

[Maxx]

i assume they are running same head and same turbo

just different bottom end with lower boost

Edited November 18, 2005 by Maxx

[Cubes]

All they have done is made it a little more street friendly.

No doubt it will be much easier to accelerate away from the lights without the lag the old wrx's are renowed for.