Note first: In another thread I posted my dyno charts "estimated" numbers
pretty much using a ruler and "eyeballing it" to line up the points. Not VERY accurate at all.
This time, I used a 90 degree right angle so the numbers for my stock runs
below vary from my other post, but are much more accurate to what I got.

Here's the specs.

Baseline 2005 Legacy GT-L 5MT
Stock except the Enkei RPM2's 18x7.5 with Pirelli P Zero Nero's
(this combo is about 2.8 pounds lighter than stock, but they are about
.15 inches taller, so the performance gain for the less weight is nearly
negated by the slightly taller overall diameter.

This is California 91 Octane crap gas too.
Stock baseline run was done with about 2400 miles on car.
CAP Stage 1 run was done with 3100 miles on car and done only
155 miles after the reflash (Cobb states it takes the ECU about 200-300 miles to FULLY learn the reflash). Harman Motive agreed but stated with my 155 miles on the reflash I was close and might have gained "maybe" another 1-2 hp if I gave the ECU a bit longer to "learn" the reflash. I probably would gain another 1-2 hp too with 5K plus miles on the car.
Dyno is Harman Motive in LA area. Dynojet dyno.

Stock Peak Power:
HP = 206 @ 5180 rpm
TQ = 215 @ 3150 rpms

Stage 1 Peak Power:
HP = 219 @ 5250 rpms
TQ = 255 @ 3425 rpms

Here's the differences at various stages of the dyno pull.


RPM----Stock HP/Torque---- Stage 1 ---- Change
2200------- 60 / 136 ------ 62 / 148 --- +2 / +12
2500------- 72 / 162 ------ 80 / 176 --- +18 / +14
3000------- 121 / 209 ----- 132 / 231 -- +11 / +22
3500------- 138 / 211 ----- 161 / 251 -- +13 / +40
4000------- 158 / 208 ----- 182 / 247 -- +24 / +39
4500------- 174 / 204 ----- 200 / 236 -- +26 / +32
5000------- 198 / 205 ----- 211 / 220 -- +13 / +15
5500------- 201 / 192 ----- 215 / 207 -- +14 / +15
6000------- 200 / 175 ----- 206 / 185 -- +6 / +10
6500------- 198 / 165 ----- 208 / 168 -- +10 / +3


Notice at PEAK HP the Stage 1 only netted me 13 hp
and at PEAK TQ the Stage 1 netted me 40 TQ.

But what's interesting is that at MANY places throughout the
rev ranges the Stage 1 actually got me more than
it did at PEAK.
At one point the Stage 1 gained 26 hp over stock.
And the biggest gains are in the midrange. I can definitely feel
the extra pull in that 3500-5500 rpm range!
It pulls slightly harder out of the gates and slightly harder
at the top too. And much smoother power delivery.
Also notice at just past 5500 rpm with the Stage 1 there's a bit of dip
in power but then at just over 6000 rpm's it jumps back UP a couple
hp and pretty much holds it until redline.

A/F Ratios:

Stock = At 3000 rpms it's around 13.8-14.0 : 1 and it holds
at that level until about 3400 rpms at which point it drops
to around 10.0 to 10.2 : 1

Stage 1 = At levels BELOW 3000 rpms the A/F is very close to stock.
But at 3000 rpms it's RIGHT at the 11.0:1 area and ranges from
11.0 to 11.5 from 3000 rpm's all the way to redline.

So it appears the Stage 1 actually leaned the A/F ratio out a bit
over stock as well.

Thoughts?

Please, someone post something like this who has an 05 STI!

Nice info!

Thanks.

I was wondering if anybody was going to respond (give a shiite). :)
I know this is primarily a Impreza board, and I did post this over
at the LegacyGt forums, but thought you guys might be interested
to see what a basically stock LGT and a simple CAP Stage 1 reflash
on the LGT does.

Later

Good info! I am always interested to see what the other 2.5s are doing. Sounds like a nice torque bump in the sweet spot. What else are you planning?

I had a chance to have a gt loaner this past monday, the sti was in for rear strut replacement (under warranty). The whole time I wondered what the sti version of this car would be like.

I'm curious to see how far people will go with the legacy mods. Most legacy drivers around here seem oblivious that they are in a performance community, let alone they have a good platform to work with. Guess that's why my car has the huge wing, and the gt doesn't. :lol:

Area under the curve owns! That a really nice increase in good useable power. I'd like to see the same sort of results with a uppipe and downpipe installed too.

Good info! I am always interested to see what the other 2.5s are doing. Sounds like a nice torque bump in the sweet spot. What else are you planning?


Nothing really. Don't like to spend too much in mods since I lease and don't keep cars long enough to make modding them excessively worth it.



I had a chance to have a gt loaner this past monday, the sti was in for rear strut replacement (under warranty). The whole time I wondered what the sti version of this car would be like.

Oh, it would be SWEET without a doubt.
With 300+ hp and torque STOCK, a 6 speed manual, Brembo brakes, slightly
stiffer and lower suspension, Recaro seats, lighter 18 inch wheels wrapped with sticky Summer rubber and the other obvious STI inputs (larger swaybar, quicker ratio steering, etc etc) and a Legacy STI would ROCK.
Price it in the mid to high $30's and lookout, it would be without a doubt
the sleeper near luxury sport sedan of the decade.
I'd own one no question! Just spare us the big wing...keep it a nice trunk lip spoiler and JDM like front lip spoiler too.