12 Bolt HP loss

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Sep 24, 2005 | 08:13 PM

obrien24

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12 Bolt HP loss

Today I finally got around to getting my car dynoed since I installed my moser 12 bolt. I previously had a 10 bolt with 4.10s and an auburn posi. The moser has 4.10s as well, with an eaton hd posi. Along with the rear swap, I installed a heavy duty steele drive shaft. My car has slp long tubes, 3" true duals dumped before the axle, lid, ported tb, gmaf, smooth bellows, and a crank pulley. I also have a custom tune by Jeremy formato. My previous numbers with the 10 bolt were 351 rwhp and 360 rwtq. With the 12 bolt I went down to 343 hp and 351 tq. I was expecting about a 10 hp loss based on what I had been told, and that wasn't far off. A loss of 8 hp and 10 pounds of tq is def. worth the change.

Sep 24, 2005 | 11:47 PM

Xtnct00WS6

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From: Sterling VA

Anyone know why there's a loss when going to a 12 bolt?

Sep 24, 2005 | 11:58 PM

Spellbound

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From: Norcal

Quote:

Originally Posted by Xtnct00WS6

Anyone know why there's a loss when going to a 12 bolt?

Heavier parts?

Sep 25, 2005 | 12:05 AM

GTO_Scott

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From: Denver, CO

Same dyno and were both numbers SAE? Things change, even on the same dyno so I wouldn't 100% trust difference in numbers unless it was same day, same dyno, same weather condtions, and SAE.

Sep 25, 2005 | 12:02 PM

BlueSix

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From: its fucking cold

The greater mass of the parts in the 12 bolt take more power to turn.

Sep 25, 2005 | 01:13 PM

6SpeedWS6Formula

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From: Chicago

i'm thinking the heavy duty steel driveshaft ate your hp.

Sep 25, 2005 | 05:04 PM

obrien24

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same dyno, different days, yes they were sae corrected, and very similar conditions. Temp was only about 5 degress difference, and humidity had a diff of less than 10% I believe as well. I know it may change somewhat in different conditions, but I just wanted ot post this up for those who may be curious about the hp losses.