LT1 Based Engine Tech 1993-1997 LT1/LT4 Engine Related

Dyno results came in bad... ideas?

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Old Mar 21, 2008 | 04:10 AM
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Dyno results came in bad... ideas?

Hey i just went and dynoed my car. I've been fixing it for a while and it's getting better.

275HP and 360Nm (265 lbs/sq ft).

The HP is about right but what's wrong with the torque? What could be taking 20% off the normal value?
Old Mar 21, 2008 | 05:32 AM
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Just curious.... why would your dyno results be given in English units for HP, and metric units for torque, requiring you to convert the torque from newton-meters to pound-feet (not lbs/sq ft)?
Old Mar 21, 2008 | 08:06 AM
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What have you done to the car?

You realize a LOT of the stuff offered for these things is complete crap. If a magazine promotes it the chances are good that the product is not.
Old Mar 21, 2008 | 12:32 PM
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I'm from Europe, they gave me hp and Nm figures. I converted so you wouldn't have to in case you wanted to just as a helper.

Basically the car is bone stock atm. Bought it in horrible condition tried to fix it up, to whatever extent i could find problems. The only thing not stock maybe is the air filter which is from a Kia, only thing i could find here to my size (SLP SS airbox...).
Old Mar 21, 2008 | 12:44 PM
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Basically your torque is low, your hp is HIGH.

You should be in the 255hp/300ftlbs range.

I dynoed 231/270 BONE stock in an A4. And this was LOW as far as average, but still 18% drivetrain loss.
Old Mar 21, 2008 | 12:44 PM
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BTW, HOLLEY makes a filter for your car.
Old Mar 21, 2008 | 01:24 PM
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I understand these oiled cotton filters aren't good cause they oil the air sensor and end up doing more damage than good. I'm looking into finding an AEM dry filter or having them make one my size
Old Mar 21, 2008 | 03:47 PM
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Only if you put too much oil on them. Used correctly, they will not hurt the MAF sensor.

Is there any way you can post the dyno sheet?

At what RPM did the engine make peak HP?

What kind of dyno was it, and what correction method did they use?
Old Mar 21, 2008 | 03:54 PM
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Originally Posted by flexus
I understand these oiled cotton filters aren't good cause they oil the air sensor and end up doing more damage than good. I'm looking into finding an AEM dry filter or having them make one my size
according to k&n they have no effect at all on the maf! which is a total lie and bull****! my maf was caked with it. but its clean now... k&n gets the thumbs down for me.
Old Mar 21, 2008 | 05:04 PM
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I've never had a problem with K&Ns.
Old Mar 21, 2008 | 05:17 PM
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Originally Posted by LSWHO
I've never had a problem with K&Ns.
usually you will only have problems if you over oil the filter
Old Mar 21, 2008 | 05:36 PM
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Originally Posted by LSWHO
I've never had a problem with K&Ns.
Me neither, if my toothbrush used a filter I would put a K&N in it.
Old Mar 22, 2008 | 04:37 AM
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Well then the dyno is made of 4 cylinders, each wheel spinned between 2. They haven't sent me the dyno yet As far as i remember tho they did it in 5th and the speed limiter came in before it could get to top revs, i just extrapolated 275, it was actually 266 @ 5200-5300.

I have no idea about correction. There was another line down there tho which said -hp loss-.
Old Mar 22, 2008 | 08:17 AM
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why the heck did they do it in 5th gear? wtf!! they should've done it in 3rd gear
Old Mar 22, 2008 | 08:18 AM
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You don't dyno an M6 in 5th gear. That is overdrive and may produce poor torque results. You dyno it in the 1:1 ratio 4th gear with an M6. Also odd that it hit the speed limiter. In 5th gear, with stock tire diameter (25.65" or 65.2 cM)) and stock 3.42:1 rear axle ratio, it would be at 157 MPH (253 kM/H) at 5,200 RPM. That would be the end of the speedo scale, but not where the speed limiter is set. The speed limiter in cars with Z-rated tires is set as 255 MPH (410 kM/H).

Because of the defined relationship of HP to torque, at 5,252 RPM torque in lb-ft will equal HP. If you had 266 HP at 5,252 RPM, you had 266 lb-ft (361 Nm). That is not necessarily the peak torque. That would typically occur below 5,252 RPM.

Not sure how you would extrapolate HP beyond 5,300 RPM. It is not a linear function, because torque is typically dropping off at that point, and HP is a product of torque and RPM.

Last edited by Injuneer; Mar 22, 2008 at 08:21 AM.



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