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My car has about 3K miles on it and I got it about 2 months ago. The only mod is a B&M. I dyno'd today at 330RWHP and 330RWTQ (SAE corrected). It pulled the EXACT same on each of the three pulls.

How does this compare with others? We had an Autotap on it while it ran and noticed it had 4 degrees of knock retard. Any idea why?
 

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Dynoed mine on 5/12/01 at Breathless.
With approx. 2000 miles on the odometer and NO modifications:

332.2 @ 5800 rpm
336.4 @ 4550 rpm


On 2001-07-14 21:46, NetJunkie spewed forth this drivel:
My car has about 3K miles on it and I got it about 2 months ago. The only mod is a B&M. I dyno'd today at 330RWHP and 330RWTQ (SAE corrected). It pulled the EXACT same on each of the three pulls.

How does this compare with others? We had an Autotap on it while it ran and noticed it had 4 degrees of knock retard. Any idea why?
_________________

Don
 

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What was the total timing? I dont remember who but someone just posted a diagram on how to manally do the IAT which would have an effect on the timing. I would imagine some of the GM techs on the forum could help out. Or anyone who has found any info.
 

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With a Vortex and B&B Prt's mine dyno'ed at 343.5hp and 344.9 ft/lbs torque. This was with 2000 miles on the car. I'll be dynoing again in about 2 weeks and with 7,000 miles on the car, I expect better numbers.
 

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TRY AND KEEP IN MIND WHEN COMPARING DYN FIG,S THAT THEY CAN BE AS DIFFERANT AS NIGHT AND DAY. THEIR ARE ALOT OF FACTORS THAT CAN CHANGE RATINGS BETWEEN DYNO,S. TEMMP, DYNO OPERATOR,THE TYPE OR MAKE OF DYNO,THE TEMP,S OF YOUR CAR OILS, AND OFCOURES THE MILES ON YOUR CAR.
I ONLY BRING THIS UP SO IF YOU SEE A FIG. THAT IS WAY OUT OF LINE YOU COULD QUESTION IT.LETS FACE IT MOST DYNO,S ARE UP FRONT WITH CORRECT HP AND TORQUE READINGS BUT THE OPERATOR THAT HAS JUST INSTALLED ALOT OF NEW SPEED PARTS FOR ALOT OF $ JUST MIGHT MAKE SURE YOUR HP READINGS ARE VERY MUCH IMPROVED.....
 

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NetJunkie,
Your numbers are good Lingenfelter says he has not had a stock Z06 dyno greater than 332 rwhp. Welcome to the world of real numbers, stay with the dyno shop you are using.
 

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Discussion Starter #9
Thanks for the info guys. I had a blast doing it. We had about 20 cars there that day, including an ACR Viper, a Mustang Cobra, and a couple of F-Bodies.

Question: I got my dyno run on a disk, but the dynojet viewer software doesn't list actual numbers on the chart. My printout says "Max Power = " and "Max Torque =" but that doesn't show on the viewer. Anyway to get that?
 

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Frank, unfortunately, at least in past releases of the "viewer" software, it excludes many of the features that are evident with the actual dynojet equipment installed in the shop. I don't know why they exclude them but it is not very useful without them.

What would be nice is if we could have a forum just for dyno results. Far too often those of you that post your dyno results do not provide any supporting information, like whether or not the #s are "corrected", what rpm at the peaks, mileage, engine temp, etc.

I am also very interested in the "shape" of the HP and TQ curves and the amount of "smoothing" applied to those curves.

Picture images of actual graphs provided by the Dynojet shop would be ideal. Such as in case of FRC Tom's dyno results (see his post in this tread), which shows a lot of these details.

On "modified" cars it is also important to see if there were any tradeoffs in the power band. In Tom's case, his results look very good and mods did not adversely affect low to mid range power characteristics.

Unfortunately, most dyno operators do not bother to capture the low end torque & power characteristics much below 2500 rpm. With as much torque as the LS6 makes even down low, it would be interesting to measure at so-called "cruising" speeds at around 1500 rpm or even lower. It's just a matter of initiating the test at lower rpm and then triggering the capture buffer built in to the Dynojet software a bit earlier during the roll on test.
 

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My best pull in my car (01 Z06) last Nov. was 340.3 hp, 340.8 tq (sae corrected). I filled up the car with Premium around the corner from the dyno shop, this supposedly resets the knock retard factor stored..... I don't know if this is BS but the pulls were good, I was happy. The car was BONE STOCK, no mods except a V1, & a CAGS plug. <2k miles @ the time. I was going to redyno the car but sold it w/9800 miles. I wonder what it would have done after it was broken-in.

I plan to Dyno the '02 @ the same miles, & same shop, I will report the difference.

Bob
 

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I dyno'd mine bone stock with about 10000 miles on it, and got SAE corrected numbers of:

340.5 HP
341.6 TQ

I agree with Big Jim's comment about how some tuners may "fudge" a bit on their "after" numbers and would always have more faith in someone who has no interest in what the numbers are. JMHO
 
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Tom Easterday dynoed his Red Z06 that we drove back from the Museum last year. It was one of the very first Z06s dynoed. We took it back to the same dyno after our mods:



His Mil Yellow Z06 dynoed much less and even with our package could only muster 350 RWHP. Many variations in the Z06 numbers, but stick with the same dyno when making comparisons on your mods.

Your numbers may be low, but don't let that fool you. I have one customer complain that he could only see 10 RWHP and 15 ft lbs on the dyno with the Halltech, but turned 12.47 @ 117.4 mph! Go figure.

Jim Hall
Halltech
www.CorvetteC5.com
 

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Frank...I have seen several requests for a dyno graph posting section. I think we all know that some discrepancy will occur because of variables such as the dyno's themselves, temp, humidity, a Republican president, etc., but there should be some consistency as well. With the 2002 coming out, it might be nice to see the similarities and/or differences. Just a thought... /phpBB/images/smiles/icon_smile.gif
 

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Frank, I read that before and found it very interesting. But I think the value is in the graph itself, not the final number. I agree that it would be difficult to compare final readings.
 

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Interesting. If I apply the normalized drive line loss factor of 14.3% derived from the 1st car (Netjunkie), to the last (Rwdyryd), and both cars are stock, then these cars differ (mathematically), as follows.

At normalized loss factor of 14.3%:

Netjunkie's LS6 @ 3k miles = 385 hp
Rwdyryd's LS6 @ 2k miles = 397 hp

Another way to look at the same comparison, is to derive the loss factor in the opposite way. By so doing, then the "normalized" loss factor becomes 11.6%, a more conservative figure, and perhaps more realistic.

At normalized loss factor of 11.6%:

Netjunkie's LS6 @ 3k miles = 373 hp
Rwdyryd's LS6 @ 2k miles = 385 hp

Another approach would be to average the two calculated loss factors which results in 13%.
(Some people believe the loss factor is as high as 16 or 17%). Then the comparison between these two cars becomes:

Netjunkie's LS6 @ 3k miles = 379 hp Rwdyryd's LS6 @ 2k miles = 390 hp

Applying a 13% (average) LF to a corrected dyno measurement of 335rwhp equates to 385hp at the flywheel. A lot of the numbers we have seen posted on this board higher than
that are from "modified" cars.

However, an essential piece of information that could help to explain differences in dyno measurements of stock Z06s is missing and poorly compensated for by the dyno measurement system. It is internal engine operating temp at the time of each test. A good approximation of this temp is the coolant or oil temp in the block. What the dyno instrumentation monitors and factors into its compensation algorithm is the OAT. This is "roughly" equivalent to the MAT, which is somewhat pre-heated to a higher temperature which the dyno cannot accurately determine.

What all this is getting at is the relative importance of doing dyno testing at a "controlled" or nominal engine operating temp. Then, for comparison purposes, either for the same car that is subsequently modified, or between cars that are 100%stock, Dynojet measurements in terms of peak values are more relavent.
 

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Discussion Starter #19
Any idea why I got the 4 degrees of knock retard? I was running 93 octane Amaco gas.

FYI... the oil temp was between 205 and 210 on each run. The temp was about 86 degrees and humidity was 26%.
 

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Had my first Dyno last Friday(the 13th!!). Have 6,250 miles on odometer.....On a DynoJet @ Morgan Motorsports in Reseda, CA.
363.7hp/352.3torque. Can't wait to do the heads/cam/dampner(underdrive pully)./phpBB/images/smiles/icon_biggrin.gif
 
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