Just dynoed my car with 100 shot
02-25-2008, 10:04 PM
#12
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Join Date: Jan 2008
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Posts: 213
RE: Just dynoed my car with 100 shot
The dyno probably isn't off. The true story is with that torque curve, its a downward slope. It should be flat or a slight hump. You're losing torque as the RPMS go up, so thats why you got big torque and low power.
Figure out what is causing you to lose torque with RPM. Once you do, and the engine makes 440 lb-ft @ 5800 rpm, then you should have 485 hp. Or so.
Figure out what is causing you to lose torque with RPM. Once you do, and the engine makes 440 lb-ft @ 5800 rpm, then you should have 485 hp. Or so.
02-25-2008, 10:16 PM
#14
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Join Date: Nov 2004
Location: Tennessee
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RE: Just dynoed my car with 100 shot
ORIGINAL: ottos
The dyno probably isn't off. The true story is with that torque curve, its a downward slope. It should be flat or a slight hump. You're losing torque as the RPMS go up, so thats why you got big torque and low power.
Figure out what is causing you to lose torque with RPM. Once you do, and the engine makes 440 lb-ft @ 5800 rpm, then you should have 485 hp. Or so.
The dyno probably isn't off. The true story is with that torque curve, its a downward slope. It should be flat or a slight hump. You're losing torque as the RPMS go up, so thats why you got big torque and low power.
Figure out what is causing you to lose torque with RPM. Once you do, and the engine makes 440 lb-ft @ 5800 rpm, then you should have 485 hp. Or so.
Quickshot, just get that thing out to the track, and you'll be able to see how good it runs. The "lean spike" is just something that happens. When you open the solenoids, the N20 comes at 1000psi, while the fuel comes out at ~50psi. Obviously the N20 is gonna get there first, without the fuel, that's where the big jump comes from. As long as it doesn't go TOO long w/o fuel, you're ok. A long N20 line, and a very short fuel line will help
02-25-2008, 10:25 PM
#15
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Join Date: Jul 2006
Location: Charlotte, NC
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RE: Just dynoed my car with 100 shot
ORIGINAL: ZW99GT
That's not how nitrous works partner. You get a huge spike, then TQ drops off as the RPM's increase. Just the nature of the beast.
Quickshot, just get that thing out to the track, and you'll be able to see how good it runs. The "lean spike" is just something that happens. When you open the solenoids, the N20 comes at 1000psi, while the fuel comes out at ~50psi. Obviously the N20 is gonna get there first, without the fuel, that's where the big jump comes from. As long as it doesn't go TOO long w/o fuel, you're ok. A long N20 line, and a very short fuel line will help
ORIGINAL: ottos
The dyno probably isn't off. The true story is with that torque curve, its a downward slope. It should be flat or a slight hump. You're losing torque as the RPMS go up, so thats why you got big torque and low power.
Figure out what is causing you to lose torque with RPM. Once you do, and the engine makes 440 lb-ft @ 5800 rpm, then you should have 485 hp. Or so.
The dyno probably isn't off. The true story is with that torque curve, its a downward slope. It should be flat or a slight hump. You're losing torque as the RPMS go up, so thats why you got big torque and low power.
Figure out what is causing you to lose torque with RPM. Once you do, and the engine makes 440 lb-ft @ 5800 rpm, then you should have 485 hp. Or so.
Quickshot, just get that thing out to the track, and you'll be able to see how good it runs. The "lean spike" is just something that happens. When you open the solenoids, the N20 comes at 1000psi, while the fuel comes out at ~50psi. Obviously the N20 is gonna get there first, without the fuel, that's where the big jump comes from. As long as it doesn't go TOO long w/o fuel, you're ok. A long N20 line, and a very short fuel line will help
So ZW seeing how you've dealt with nitrous for a while now do you see anything extremely abnormal with the graph?
02-26-2008, 08:13 AM
#16
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Join Date: Jan 2004
Location: United States
Posts: 12,575
RE: Just dynoed my car with 100 shot
ORIGINAL: ottos
The dyno probably isn't off. The true story is with that torque curve, its a downward slope. It should be flat or a slight hump. You're losing torque as the RPMS go up, so thats why you got big torque and low power.
Figure out what is causing you to lose torque with RPM. Once you do, and the engine makes 440 lb-ft @ 5800 rpm, then you should have 485 hp. Or so.
The dyno probably isn't off. The true story is with that torque curve, its a downward slope. It should be flat or a slight hump. You're losing torque as the RPMS go up, so thats why you got big torque and low power.
Figure out what is causing you to lose torque with RPM. Once you do, and the engine makes 440 lb-ft @ 5800 rpm, then you should have 485 hp. Or so.
If you don't KNOW then do not offer tech advice. Talking about what your brothers girlfriends uncle told you is not knowing... so don't post it up!
Something is wrong with my PC, but if your on some sort of funky dyno, I would do what ZW said and take it to the track. That will tell the real story... dynos are just reference numbers anyway.
In any case, going from 220 WHP to 306 WHP isn't THAT far off for a 100 shot... its probably just a slight difference that day in the dyno.
edit: I can see the dyno now, and I see the problem! Dyno dynamics FTL! I have seen some amazingly low power numbers come out of them, espcially HP numbers. It can't be good when you acutally roll the thing around on the floor... IMO they are no better than the portable dynos at car shows (about the same thing).
02-26-2008, 09:10 AM
#17
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Thread Starter
Join Date: Jul 2006
Location: Charlotte, NC
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RE: Just dynoed my car with 100 shot
In any case, going from 220 WHP to 306 WHP isn't THAT far off for a 100 shot... its probably just a slight difference that day in the dyno.
edit: I can see the dyno now, and I see the problem! Dyno dynamics FTL! I have seen some amazingly low power numbers come out of them, espcially HP numbers. It can't be good when you acutally roll the thing around on the floor... IMO they are no better than the portable dynos at car shows (about the same thing).
edit: I can see the dyno now, and I see the problem! Dyno dynamics FTL! I have seen some amazingly low power numbers come out of them, espcially HP numbers. It can't be good when you acutally roll the thing around on the floor... IMO they are no better than the portable dynos at car shows (about the same thing).
Weird the general consensus among a lot of shops and on other forums is that the Dynamics are a better dyno than say a Dynojet. They say they are much better to tune on and such but w/e doesn't make much of a difference to me lol.
02-26-2008, 11:26 AM
#18
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RE: Just dynoed my car with 100 shot
ORIGINAL: 01GT4.6
that comment was a joke right?
ORIGINAL: ottos
Once you do, and the engine makes 440 lb-ft @ 5800 rpm, then you should have 485 hp. Or so.
Once you do, and the engine makes 440 lb-ft @ 5800 rpm, then you should have 485 hp. Or so.
Just saying he should do the nitrous shot at a higher RPM for more power.
http://www.go-fast.org/z28/photos/nitrous/n2odyno.gif
IfQuicKShotturned onNOS atsay 4500 rpm andcould make440 lb-ft at 5800 or 5500 rpm, then he'd have 460 - 485 hp. Since 440lb-ft * 5500rpm / 5252= 460hp
Probably an optimistic number but its possible if the shortblock holds... alright, imdone being a smartass.
02-26-2008, 01:29 PM
#19
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Join Date: Jan 2005
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Posts: 371
RE: Just dynoed my car with 100 shot
Everybody does realize that dyno's measure torque and uses that with rpm to calculate horsepower, right? Horsepower is just a figure used to help sell tractors to Farmer John back in the day.
HP = (Torque X RPM)/5252
So using the above calculation with the OPs peak torque:
HP = (490 X 2800)/5252 = 261 HP
Everything adds up to me. I swear it shouldbe a requirement for the dyno owners to explain this to every customer.
HP = (Torque X RPM)/5252
So using the above calculation with the OPs peak torque:
HP = (490 X 2800)/5252 = 261 HP
Everything adds up to me. I swear it shouldbe a requirement for the dyno owners to explain this to every customer.
02-26-2008, 02:06 PM
#20
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Join Date: Nov 2004
Location: Tennessee
Posts: 7,797
RE: Just dynoed my car with 100 shot
ORIGINAL: Quick Shot xMLx
Yea I did a quick pull on the highway but besides that it won't see too much street action. I'm definitely one to frequent the drag strip and once it opens back up I'll go down there. Well it might be open this weekend depending on the weather so we'll see
So ZW seeing how you've dealt with nitrous for a while now do you see anything extremely abnormal with the graph?
ORIGINAL: ZW99GT
That's not how nitrous works partner. You get a huge spike, then TQ drops off as the RPM's increase. Just the nature of the beast.
Quickshot, just get that thing out to the track, and you'll be able to see how good it runs. The "lean spike" is just something that happens. When you open the solenoids, the N20 comes at 1000psi, while the fuel comes out at ~50psi. Obviously the N20 is gonna get there first, without the fuel, that's where the big jump comes from. As long as it doesn't go TOO long w/o fuel, you're ok. A long N20 line, and a very short fuel line will help
ORIGINAL: ottos
The dyno probably isn't off. The true story is with that torque curve, its a downward slope. It should be flat or a slight hump. You're losing torque as the RPMS go up, so thats why you got big torque and low power.
Figure out what is causing you to lose torque with RPM. Once you do, and the engine makes 440 lb-ft @ 5800 rpm, then you should have 485 hp. Or so.
The dyno probably isn't off. The true story is with that torque curve, its a downward slope. It should be flat or a slight hump. You're losing torque as the RPMS go up, so thats why you got big torque and low power.
Figure out what is causing you to lose torque with RPM. Once you do, and the engine makes 440 lb-ft @ 5800 rpm, then you should have 485 hp. Or so.
Quickshot, just get that thing out to the track, and you'll be able to see how good it runs. The "lean spike" is just something that happens. When you open the solenoids, the N20 comes at 1000psi, while the fuel comes out at ~50psi. Obviously the N20 is gonna get there first, without the fuel, that's where the big jump comes from. As long as it doesn't go TOO long w/o fuel, you're ok. A long N20 line, and a very short fuel line will help
So ZW seeing how you've dealt with nitrous for a while now do you see anything extremely abnormal with the graph?
Here's my graph on the 100 shot. TQ jumps up big, and drops off.
