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Discussion Starter #1 (Edited)
Hey, I bought an 01 cobra recently and Im very happy about the purchase. The previous owner dynoed it with off road x, magnaflow catback, and a CAI. The dyno looks good to me until the torque and horsepower meet, and then it gets a little choppy. Looks like it might need some more ignition power. I dont think its detonation, but I dont have the corresponding A/F to confirm. Any dyno guru's know whats going on? Also, Im used to pushrod engines on the dyno, I dont think I have seen corresponding "jumps" in torque and hp like on this run. Anyone make heads or tails of that?? There are a couple in the torque band that are very noticeable, and not as noticeable in hp, but you can still see it. Thanks in advance for the info.
 

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Can you post the dyno sheet?

(You didn't happen to buy this Cobra in MI, did you? Thinking I might know who used to own it)

:)
 

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Discussion Starter #3
Yeah I got it posted now, im a dummy, sorry about that. Yeah I bought it from MI, I bought it from BDC_Cbra01... You know him?
 

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Overall the curve looks pretty normal / good for that car. The jaggies could be the knock detector kicking in. If it is, and you can eliminate the pinging, the jaggies will go away and you will gain a bit more top end.

BTW, there is nothing special about the point where torque and horsepower meet. They always meet somewhere because power is torque multiplied by RPM. Where they meet is determined by the units of measurement. If power is in HP and torque in ft. lbs., then they always meet at 5,252 RPM. If you measure torque in N-m and power in KW then they meet at a different RPM.
 

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Discussion Starter #5
I understand that there is nothing special about when or where the hp and torque curves meet, I was just using it to describe the point where the curves got a little choppy. Thanks for the info though, I didnt think about the knock detector. What about the corresponding "jumps" in HP and Torque?
 

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JD93GT said:
Yeah I got it posted now, im a dummy, sorry about that. Yeah I bought it from MI, I bought it from BDC_Cbra01... You know him?

No prob. I tried to PM you back, but your box was full (yes that was Brent's Cobra BTW; a great car, it was a garage queen-superclean!!). enjoy the cobra :) -Harry
 

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Discussion Starter #7
Im happy I bought it, love the low miles!
 

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Discussion Starter #9
Can anyone tell me why the hp and torque "jumps" at the same time throughout the curves. The Hp you kinda have to look for, but the jumps in the torque stand out like a sore thumb, any ideas?
 

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JD93GT said:
Can anyone tell me why the hp and torque "jumps" at the same time throughout the curves.
Because HP is TQ times RPM, if the TQ "jumps" -- whether upward or downward -- then it will also affect HP.

The broad, smooth TQ jumps you see are usually caused by a complex interaction of intake geometry, cam timing, A/F ratio, exhaust tuning, etc. The short, jagged TQ jumps are usually caused by the knock detector (pinging).
 
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