285 whp!

[dynomatt]

Hey Chuck,

Consistent with the power figures we got, the standard injectors were only running about 75%...we'd banked on getting more, and hence needing more fuel, but didn't happen.

Intake is stock, save that the MAF is gone, exhaust is standard headers with a 2" system joined at a y-pipe under the floor somewhere, then 2 1/2" out with one resonator and one muffler.

Transmission is a stock 6 speed.

[dynomatt]

Here's my chart.


Was actually 190hp ATW.

Matt

[RallyBob]

Originally Posted by dynomatt

Bob...I've got exactly the same specs as you...STi valves (not oversized though), compression, porting, stand alone ECU.

Interestingly I only got 165hp. To this day I've been confused by that, as mathematically, we should have been up where you were.

Your cam specs though?

The cam we had ground are the big power maker IMO. The stock cams have miniscule valve lift, and the duration IIRC was something like 196° @ .050" . The new cams we have are 244° @ .050", so we're looking at nearly 50 degrees more duration than stock, plus a massive valve lift increase (.444"/11.27 mm intake, .460"/11.68 mm exhaust lift).

Even with the larger valves and porting, I don't feel the headwork I performed was worth that much (yet). The stock, unported heads flow enough air for almost 425 bhp. My porting work increased the potential only to about 450-455 hp, athough it probably made getting to our existing power levels a bit easier. The trick is extracting that potential by matching the rest of the components. The stock cams for example, reduce the hp potential down to 325 bhp simply by virtue of the low valve lift (the duration not being taken into consideration).

I do agree that something seems 'wrong', 165 hp seems to be about the same as a stock engine makes. My stock 5-speed WRX (with 2.5" cat-back Stromung and K & N panel filter) made 184.6 whp back in June of 2001 on the exact same Dynapack dyno that Jack's 3.3 RS was dynoed on, for comparison's sake.

[RallyBob]

Originally Posted by cdigerlando

What are you using for fuel injectors? Intake? Exhaust? Transmission

Bob, are you tuned using race fuel?

Also Bob is using a 5 speed, which has a lot less drive train loss.

The stock injectors get maxed out right away.

I *believe* the injectors are either Nissan or stock STI...I just know they're yellow!

Jack's car is tuned only on 93 octane pump gas. Max timing is 41 degrees BTDC (same as previous tunes), the timing at crank-over is 12 degrees, timing at 1100-1200 rpm idle is 15 degrees.

[longassname]

Can you post your dyno plots? I'd be interested to see the dyno settings. You have a correction factor or something set different than the dyno plots others here have been comparing your results to.

Originally Posted by RallyBob

Your cam specs though?

The cam we had ground are the big power maker IMO. The stock cams have miniscule valve lift, and the duration IIRC was something like 196° @ .050" . The new cams we have are 244° @ .050", so we're looking at nearly 50 degrees more duration than stock, plus a massive valve lift increase.

Even with the larger valves and porting, I don't feel the headwork I performed was worth that much (yet). The stock, unported heads flow enough air for almost 425 bhp. My porting work increased the potential only to about 450-455 hp, athough it probably made getting to our existing power levels a bit easier. The trick is extracting that potential by matching the rest of the components. The stock cams for example, reduce the hp potential down to 325 bhp simply by virtue of the low valve lift (the duration not being taken into consideration).

I do agree that something seems 'wrong', 165 hp seems to be about the same as a stock engine makes. My stock 5-speed WRX (with 2.5" cat-back Stromung and K & N panel filter) made 184.6 whp back in June of 2001 on the exact same Dynapack dyno that Jack's 3.3 RS was dynoed on, for comparison's sake.

[longassname]

That difference in correction factor or gearing input is what is tempting some to call bs. The crank hp they are infering from it is out of the realm of possiblity but when you correct your wheel hp readings for the eg33 by the same factor as the difference between your stock wrx wheel hp readings and the readings found on the dyno's used for plots being compared to yours you get the same results.

165/184.6*212= 189.5 hp

essentially the same hp as a chiped svx with a 5 spd

[RallyBob]

Originally Posted by longassname

Can you post your dyno plots? I'd be interested to see the dyno settings. You have a correction factor or something set different than the dyno plots others here have been comparing your results to.

I haven't seen my WRX dyno plots in years...that was 7 year ago after all. As far as the 3.3RS dyno plots, Jack is reluctant to release them. So that is beyond my control. IIRC a bone-stock WRX made 175-177 whp on their dyno, so my minimal mods added a few hp. I suspect that the swap to full synthetic didn't hurt either (engine and driveline).

[RallyBob]

Originally Posted by longassname

That difference in correction factor or gearing input is what is tempting some to call bs. The crank hp they are infering from it is out of the realm of possiblity but when you correct your wheel hp readings for the eg33 by the same factor as the difference between your stock wrx wheel hp readings and the readings found on the dyno's used for plots being compared to yours you get the same results.

165/184.6*212= 189.5 hp

essentially the same hp as a chiped svx with a 5 spd

I'm afraid I'm not understanding what you're saying. Are you speaking of the driveline losses being different?

[longassname]

That's a shame; they would be interesting to see but they are his and he certainly has no responsibility to share them. Just be warned that someone is running around using your wheel hp readings to try to make a case that the factory engine management is seriously flawed and that there is 60-70 crank hp to be found by installing stand alone engine management on a stock svx.

Originally Posted by RallyBob

I haven't seen my WRX dyno plots in years...that was 7 year ago after all. As far as the 3.3RS dyno plots, Jack is reluctant to release them. So that is beyond my control. IIRC a bone-stock WRX made 175-177 whp on their dyno, so my minimal mods added a few hp. I suspect that the swap to full synthetic didn't hurt either (engine and driveline).

[longassname]

No I'm not speeking of driveline loss. I'm speaking of some difference in dyno calibration or correction factors entered. Without seeing the actual plots so I can see what the settings are I can't say what is causing the difference in the measurements.

The plots that are being compared to yours have all been from machines that read a stock 5 spd wrx as having 165 wheel hp. Your said your machine reads a stock wrx as having 184.6 hp. Taking the factor of that difference and applying it to the measurements for a stock eg33 engine with a 5 spd we suddenly find that your measurements match those taken by everyone else.

Originally Posted by RallyBob

I'm afraid I'm not understanding what you're saying. Are you speaking of the driveline losses being different?

[SVXRide]

Bob,
Can you release just the correction factor used on the EG33RS dyno runs? (SAE smoothing?)
-Bill

[RallyBob]

Originally Posted by longassname

No I'm not speeking of driveline loss. I'm speaking of some difference in dyno calibration or correction factors entered. Without seeing the actual plots so I can see what the settings are I can't say what is causing the difference in the measurements.

The plots that are being compared to yours have all been from machines that read a stock 5 spd wrx as having 165 wheel hp. Your said your machine reads a stock wrx as having 184.6 hp. Taking the factor of that difference and applying it to the measurements for a stock eg33 engine with a 5 spd we suddenly find that your measurements match those taken by everyone else.

Understood. Like I said, my car had a few bolt-ons, albeit nothing major. Expect an average stock 2002 WRX to make 172-177 whp on that same dyno. Given that it is a Dynapack 'hub' dyno, the wheels and tires are taken out of the equation altogether. So I expect it to read a few hp higher than a Dynojet or Dyno Dynamics or Mustang, etc as the wheel/tire inertia is out of the equation.

We must also keep in mind that the EG33 that was 'stock' was in fact bolted to a 5-speed transmission. And it did have equal length headers and a 3" exhaust. And it did have the cold air box, which genuinely reduces intake air temps. It also probably has 40-50 hours of dyno time on it, thanks to the use of the car for the EFI-101 classes as a test vehicle. Hence the increase from the baseline 212 whp to 221 whp with no other changes to the engine. If that number is 10% lower on other dynos...so be it, I won't argue that case, as the car has not been on other dynos therefore I cannot compare results.

We all know dynos are only tools, and arguing the hp one brand makes in Colorado Springs vs. another brand in NYC is a moot point. Dynos vary, as do conditions, fuel, and engines.

However the increases we have seen from modifications performed cannot be denied (from 221 to 285 whp and ultimately 292 whp after more tuning). Even if the 'real' hp increase is not 71 whp, but rather a reduced percentage of that number, it still represents a 32% increase in power over what the same engine had on the same dyno prior to the modifications. And ultimately that is what matters to me the most. Making accountable gains. It shows up in the lap times the car turned at VIR (nearly 10 seconds per lap faster, albeit with new tires and spring rates accompanying the engine mods), and in the speeds at the end of the straights. Last year 140-142 was observed, this year 152-154 mph was observed. Partially I'm sure from the increase in corner exit speeds, but partially from the greater hp too.

[RallyBob]

Originally Posted by longassname

That's a shame; they would be interesting to see but they are his and he certainly has no responsibility to share them. Just be warned that someone is running around using your wheel hp readings to try to make a case that the factory engine management is seriously flawed and that there is 60-70 crank hp to be found by installing stand alone engine management on a stock svx.

Please dont think that I believe there is nearly that much hp from management alone. I believe it was from the cumulative effect of everything. For example, I am not surprised that the engine 'likes' exhaust flow, as my flow results showed the head flow to be very weak in that regard. I believe that was the largest contributing factor in conjunction with the management upgrade. Either modification on their own would probably not have given even 50% of the results, I think it was a matter of achieving complimentary balance, nothing more.

That said, perhaps I should never have said the car made 'X amount' of power, but instead should have interpreted it as a 'sizeable percentage increase' in hp and given that percentage. Because regardless of the numbers, high or low, there will always be doubters who think the numbers are inflated, and then there will always be those who think that 'there's something wrong' and it should make more power.

Regards,

[longassname]

No worries,

The person missusing your numbers has a history of missrepresenting and slanting things to support what he wants. I'm sure you are a victim rather than a perpetrator. With the source of the discrepancies identified I'm sure no one will question the gains from your mechanical modifications.

Originally Posted by RallyBob

Please dont think that I believe there is nearly that much hp from management alone. I believe it was from the cumulative effect of everything. For example, I am not surprised that the engine 'likes' exhaust flow, as my flow results showed the head flow to be very weak in that regard. I believe that was the largest contributing factor in conjunction with the management upgrade. Either modification on their own would probably not have given even 50% of the results, I think it was a matter of achieving complimentary balance, nothing more.

That said, perhaps I should never have said the car made 'X amount' of power, but instead should have interpreted it as a 'sizeable percentage increase' in hp and given that percentage. Because regardless of the numbers, high or low, there will always be doubters who think the numbers are inflated, and then there will always be those who think that 'there's something wrong' and it should make more power.

Regards,

[dynomatt]

Hey Bob,

Taken from this post back in March last year !!!

http://www.subaru-svx.net/forum/show...&postcount=257

My engine specs have been decided.

I'm using 98 WRX valves, springs, retainers and gutted SVX buckets, custom shims for in between.

The intake cams have 10.0mm lift, with 230 degrees duration at .050.

The exhaust cams have 10.5mm lift with 236 degrees duration at .050.

Engine analyser pro shows a number of 375hp at 7500rpm. Real world will be probably closer to 330hp.

So I'm only using 10mm of lift and 230 of duration at 50 thou. Similar, but certainly less than you.

I should also clarify. On reviewing my dyno chart (copy attached) it seems we managed 190 atwhp. Still, far short of what we were anticipating.

Regardless, mine is coming out this weekend to measure the timing. If it's way out, then I'll be motivated to fix it again...if it's dead on, then it's time for the garbage tip.

Matt