With the torque showing no signs of slowing down, you'd expect more hp as the tach rises.
Looking at the chart, torque starts dropping after 5300. Looks like they stop logging at about 5500. The small turbo is probably maxed out by then. Just one of the compromises.
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That is true LBJay but we also know GM has this ENg in the mules making 300 BHP.
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This is a flywheel dyno and not a wheel dyno. It might also have mathmatical smoothing algorithym applied to it to make it look better for publication.
Looking at the chart, torque starts dropping after 5300. Looks like they stop logging at about 5500...
The reason the HP and tq are dropping off is because they let off the gas at 5300RPM. Maybe that's what RPM they have limited it to in the tuning? Take away the RPM limitation (point at which they let off the gas), and extend the graph up, and here's what you get.
I know it might not be linear up to 7k RPM, but you get the picture. I'd bet GM is way underrating these by using a lower redline as their rating point.
Let me be the 1st to guess that bone stock, and moving the redline up to 7k in the ECM, it should dyno 240+ HP to the wheels, and that's at the stock boost levels. Throw in some race gas and up the boost about 6psi and it should see 300+ RWHP. Just .02 from a long time performance guy who has seen a few turbos in his day. (Check out my home page...) I could be way off on this, but that dyno graph they published jumped off the page, slapped me in the face, and told me it was time to reveal it's hidden secret. It's WAY too obvious to me that they quit the dyno pull at 5300RPM.
The reason the HP and tq are dropping off is because they let off the gas at 5300RPM.
The GM graph is from an engine brake dyno. The engine is run at full throttle and the dyno places a load on the engine to hold it at an RPM and take a torque measurement.
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Quote:
Originally Posted by LBJay
The GM graph is from an engine brake dyno. The engine is run at full throttle and the dyno places a load on the engine to hold it at an RPM and take a torque measurement.
Does anyone know what the rod length is in the LNF? The stroke x bore lends itself to high RPM power, and if the rod ratio is high enough (1.70 - 1.75), this could be a KILLER engine with a bigger turbo. I have a feeling that the powerband is limited by the turbo. I would be disappointed if GM put short rods in it.
Does anyone know what the rod length is in the LNF? The stroke x bore lends itself to high RPM power, and if the rod ratio is high enough (1.70 - 1.75), this could be a KILLER engine with a bigger turbo. I have a feeling that the powerband is limited by the turbo. I would be disappointed if GM put short rods in it.
Assuming the deck heigth stays the same(I bet it does) theyd almost have to put in longer rods.
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Spooled,
Start a seperate thread for this. Maybe FrankC5R knows the answer to your question.
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Location: Rosamond, CA - Home of Willow Springs Raceway
Magnaflow posted a dyno sheet showing stock and 3" exhaust. Check out the GXP section.
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2007 Cool GXP with Darkside Top, 5 spd, Ebony Cloth, Monsoon with Single CD, Sport Pedals, XM, A/C
Mods - Solo Street/Race Exhaust, K&N Drop-in Air Filter, EDAL
I am currently the owner of a heavily modified WRX, suspension, brakes, HP (>400). I don't *plan* on doing that again, but what a ride!
This GXP looks like my next ride. Just hope my WRX last long enough ... 400 + HP takes its toll over 60K miles. I am convinced turbos are THE way to go. Conservative gas mileage with an easy foot, but a blast of HP when you want. The WRX forums taught me what WOT means.
This torque curve is clearly limited by the ECU. Its easy to imagine simple changes to let it open up. This flat curve is definitely controlled by the ECU so someone will soon figure out how to reprogram.
D@mn you forums!!! My life was so simble, so ... ... boring before!!!
I am currently the owner of a heavily modified WRX, suspension, brakes, HP (>400). I don't *plan* on doing that again, but what a ride!
Linear Mode
