Shortys vs Long Tubes

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Dec 27, 2006 | 06:38 PM

STL94LT1

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Shortys vs Long Tubes

I found an old dyno sheet comparing Hooker shortys/stock cats vs EM long tubes/Dynatech 3" PowerCats. Thought you all might be interested in seeing the comparison.

I think the peak hp/tq was limited by a smallish camshaft. But, you can see a considerable gain in low end and mid range power.

Dec 27, 2006 | 06:56 PM

biggrizzly

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3hp doesn't seem that much though. I figured like a 8-10hp difference between shorties and LTubes.
Good comparison for the shortie camp I'd say.

Dec 27, 2006 | 07:22 PM

jsavoy

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Dec 27, 2006 | 07:28 PM

STL94LT1

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Quote:

Originally Posted by biggrizzly

3hp doesn't seem that much though. I figured like a 8-10hp difference between shorties and LTubes.
Good comparison for the shortie camp I'd say.

Yeah, I was disappointed with the peak numbers. But, up until around 5500 rpms there was a decent gain. The camshaft peaked at 5800.

Dec 27, 2006 | 08:05 PM

Travis93

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I think the torque numbers are most imporant in this compairason. 20 foot/pounds is quite a bit and its all the way through the test.

Dec 27, 2006 | 08:28 PM

biggrizzly

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Quote:

Originally Posted by Travis93

I think the torque numbers are most imporant in this compairason. 20 foot/pounds is quite a bit and its all the way through the test.

I think the torque for the shorties was 318.2 - that would only make a 12 foot pound difference. The image is a little blury but if you look at the increments of 10 foot lbs, it would make the curve for the shorties around 318 to 320. Still this is pretty good increase in torque for the LT over the shorts.

Dec 27, 2006 | 08:52 PM

Zix

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From: Phoenix AZ

Quote:

Originally Posted by biggrizzly

3hp doesn't seem that much though. I figured like a 8-10hp difference between shorties and LTubes.
Good comparison for the shortie camp I'd say.

Even with 20+ ft/lbs of torque more throughout almost the entire RPM range in favor of the long tubes? And then the 12-15 HP increase throughout most of the RPM range as well...

Obviously the exhaust is NOT the restriction here in the upper RPM ranges, which is why there isn't much of a difference in peak power numbers.

The LT's spanked the shorties...that's pretty apparent.