Odd dyno today?
Thread Starter
Instructor
Joined: Jan 2005
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From: Snohomish
Odd dyno today?
Took my 2004 Vortech SC Z06 into the dyno today, and the results looked odd to me as a novice. I was under the assumption that HP and TQ crossed at 5200 RPM's. Not so on mine. According to the graph, TQ jumped up much faster than HP (about 340 at 2.8K RPM's) and stayed higer than HP across the band to 5.8K where TQ/HP met, then TQ started to drop off.
Going back to the dyno next week, the AFR meter on their machine wasn't working so they gave me a freebie today. Today's run only went to 5.9K: 498.8 HP,450TQ. Frankly, I expected better with the 30 tooth pulley.
Any explanations or suggestions out there before next weeks dyno run?
Thanks, Roger
Going back to the dyno next week, the AFR meter on their machine wasn't working so they gave me a freebie today. Today's run only went to 5.9K: 498.8 HP,450TQ. Frankly, I expected better with the 30 tooth pulley.
Any explanations or suggestions out there before next weeks dyno run?
Thanks, Roger
Team Owner
Joined: Jul 2002
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From: This city NEVER sleeps! Frank's back yard!
5250 - it is mathematical - torque = hp at this rpm level. Check the graph, the hp and torque gradients on the side don't increase at the same rate, this is why it appears that the torque and hp don't cross at 5250 - equalize the two gradients, and you'll see that your engine isn't a freak!
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From: http://www.mphparts.com 800-364-1975
Ummm, that's weird. TQ and HP *always* cross at 5252RPM.
HP = Torque * RPM / 5252
I don't know of any dynos that measure HP and TQ separately -- from what I understand, they derive torque based on the ability of your car to rotate a known mass, then calculate HP based on TQ and RPM... so I am not sure how you ended up with an odd result like that.
HP = Torque * RPM / 5252
I don't know of any dynos that measure HP and TQ separately -- from what I understand, they derive torque based on the ability of your car to rotate a known mass, then calculate HP based on TQ and RPM... so I am not sure how you ended up with an odd result like that.
Thread Starter
Instructor
Joined: Jan 2005
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From: Snohomish
Thanks-
It does appear that the graphs aren't plotted exactly the same. I hadn't noticed, the HP graph (separate fron the TQ graph) starts at 0. The TQ graph below it starts at 50. Must have different scales. Next time I'll ask if they can plot it all on one graph.
Roger
It does appear that the graphs aren't plotted exactly the same. I hadn't noticed, the HP graph (separate fron the TQ graph) starts at 0. The TQ graph below it starts at 50. Must have different scales. Next time I'll ask if they can plot it all on one graph.
Roger
Former Vendor
Joined: Feb 2004
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From: Las Vegas NV
St. Jude Donor '06 & '12
Originally Posted by diynoob
they derive torque based on the ability of your car to rotate a known mass, then calculate HP based on TQ and RPM... so I am not sure how you ended up with an odd result like that.
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Supporting Vendor
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From: http://www.mphparts.com 800-364-1975
Originally Posted by DT
Actually I think it's:
Acceleration = Money X Time
Acceleration = Money X Time
I think it's closer to:
Acceleration = Money^3 + Time^2
(the carats indicate a power of 3 or power of 2)
Money X Time makes Acceleration too linear of a function, and we know that to get more incremental acceleration you have to spend exponentially more money... or, exponentially more time, albeit to a lesser extent than the money.
Advanced
Joined: Apr 2005
Posts: 52
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From: Ventura CA
Be careful with the 30 tooth pully on the ls6... my engine blew up on the dyno with just 500 mi on the motor which was a new warrenty replacement that I got with 5800 mi on the car. Broke a piston while pulling 10 lbs of boost. Bad day! but I ended up with what I wanted, one of Andy's forged blower motors.
Mike
Mike
Thread Starter
Instructor
Joined: Jan 2005
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From: Snohomish
Mike-
I sent you a PM.
Did you stay with Vortech?
I know I'm on he ragged edge. I wish I knew what my AFR was. I've been thinking about doing Alky-
A&A forged and MORE power may be in my future also if I KABOOM.
Roger
I sent you a PM.
Did you stay with Vortech?
I know I'm on he ragged edge. I wish I knew what my AFR was. I've been thinking about doing Alky-
A&A forged and MORE power may be in my future also if I KABOOM.
Roger
Advanced
Joined: Apr 2005
Posts: 52
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From: Ventura CA
Yes, I am running the Vortech kit originally with a S trim that Andy installed over two years ago. When mine gave out Andy said he was suprised that it lasted as long as it did! With the original ls6 that came with the car the 30 tooth was fine! It lasted about a year and a half and 3000 FUN miles!
The reason the engine was replaced under warranty was because a lifter collapsed and beat the sh*t out of the cam and sent metal throught the engine. With the blower back on the new engine and 500 mi for break-in and BOOM! I am also now running a T trim!
Initially I was having problems with belt slippage but hopefully solved my problems with a kevlar belt. So far no slippage problems
Next step is the 28 tooth sc pulley with the 32 tooth jackshaft pulley.
Call Andy! I know he doesn't do much with Vortech anymore but I am sure he would be glad to help any way he can! Be careful until you get a good tune and know where your AFR is!
Mike
The reason the engine was replaced under warranty was because a lifter collapsed and beat the sh*t out of the cam and sent metal throught the engine. With the blower back on the new engine and 500 mi for break-in and BOOM! I am also now running a T trim!Initially I was having problems with belt slippage but hopefully solved my problems with a kevlar belt. So far no slippage problems
Next step is the 28 tooth sc pulley with the 32 tooth jackshaft pulley. Call Andy! I know he doesn't do much with Vortech anymore but I am sure he would be glad to help any way he can! Be careful until you get a good tune and know where your AFR is!
Mike
Thread Starter
Instructor
Joined: Jan 2005
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From: Snohomish
Thanks!
I emailed Andy yesterday (him back to me saying lets talk!) and I have yet to call him to discuss Alky as a power adder/safety measure. I'll have to follow through and discuss this with him and maybe add his alky kit to my Z-
Roger
I emailed Andy yesterday (him back to me saying lets talk!) and I have yet to call him to discuss Alky as a power adder/safety measure. I'll have to follow through and discuss this with him and maybe add his alky kit to my Z-
Roger