Puzzled by Dyno last night ...any ideas?
Puzzled by Dyno last night ...any ideas? I wanted to get my car dynoed before we install the LS6 intake so I set up and appt to have it done last night at Ferrari Custom Car and Truck in Sterling where they have the dynojet. I had my car dynoed May 2003 with only the following done to the car:
1. Whisper Lid
2. Ported MAF
3. Free Air Mod
4. Loud Mouth Catback
The numbers were
323.3 RWHP
335.1 TRQ
We told the guys there what I had dynoed and that since we added
1. SLP LT's
2. Gutted Cats
They did 3 pulls but on the 3rd they stopped because the numbers were so low the first two times and wanted to let the car cool down and add a fan. They said that the engine might be too hot. The other dyno place did run a fan and was open little garage. The dynojet place had it closed up and no fans. After the car sat and fans ran on it for about 30 minutes the final was
329.48 RWHP
345.86 TRQ
As you see the numbers went up after the car cooled down and they ran the fans. It should be higher since I have the LT's. I figured I'd dyno about 340 maybe. I was pretty disappointed last night
. So anyone have any clue why the HP is so low?? We thought it might be because of the front 02 sensors being bad but the Fuel ratio was steady at 12.5
Dyno May 2003
Dyno Nov 2006
1. Whisper Lid
2. Ported MAF
3. Free Air Mod
4. Loud Mouth Catback
The numbers were
323.3 RWHP
335.1 TRQ
We told the guys there what I had dynoed and that since we added
1. SLP LT's
2. Gutted Cats
They did 3 pulls but on the 3rd they stopped because the numbers were so low the first two times and wanted to let the car cool down and add a fan. They said that the engine might be too hot. The other dyno place did run a fan and was open little garage. The dynojet place had it closed up and no fans. After the car sat and fans ran on it for about 30 minutes the final was
329.48 RWHP
345.86 TRQ
As you see the numbers went up after the car cooled down and they ran the fans. It should be higher since I have the LT's. I figured I'd dyno about 340 maybe. I was pretty disappointed last night
. So anyone have any clue why the HP is so low?? We thought it might be because of the front 02 sensors being bad but the Fuel ratio was steady at 12.5 Dyno May 2003
Dyno Nov 2006
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Originally Posted by JakeY2KZ
12.5 a/f is not that great...get it up to around 13 across the board and get rid of the ported MAF. Your numbers should increase after fixing those 2 things.
The dyno in 2003 was SAE. This recent one was STD. I didnt realize about the factor till last night. If that is the case then the numbers I had in 2003 in SAE would be higher? And now the STD #'s would be lower if they were SAE...and now my numbers are lower then before the headers??....correct?? 
Uggh if that's the case then something seriously is messed up I will get a stock MAF but I plan on installing an LS6 instake soon and then get it tuned so I guess I wont bother getting it dynoed before I do so
One another note...that day in 2003 when I had it dynoed most everyone was surprised it dynoed that high and thought it should be lower so I dont know. Everyone else that was there that day had their numbers be right on.
Uggh if that's the case then something seriously is messed up I will get a stock MAF but I plan on installing an LS6 instake soon and then get it tuned so I guess I wont bother getting it dynoed before I do soOne another note...that day in 2003 when I had it dynoed most everyone was surprised it dynoed that high and thought it should be lower so I dont know. Everyone else that was there that day had their numbers be right on.
Dont worry too much about dyno numbers. It should only be used as a tool to tune your car. Does the car feel stronger after the LT's and gutted cats? Two different dyno's almost 3 years apart, one with correction factors and the other without are most likely not even going to be close. If you want to see dyno improvements with mods either do before and after pulls on the same dyno or take it to the track and look for improvements there. Don't let this get you down. I'm sure you are making more power and the car is stronger.
By the way, those flames are sweet!
By the way, those flames are sweet!
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Originally Posted by 2002blackZ
Dont worry too much about dyno numbers. It should only be used as a tool to tune your car. Does the car feel stronger after the LT's and gutted cats? Two different dyno's almost 3 years apart, one with correction factors and the other without are most likely not even going to be close. If you want to see dyno improvements with mods either do before and after pulls on the same dyno or take it to the track and look for improvements there. Don't let this get you down. I'm sure you are making more power and the car is stronger.
By the way, those flames are sweet!
By the way, those flames are sweet!
. Yes the car definetely feels stronger and felt stronger after the LT's. The LT's were installed March 2004 and the cats gutted themselves out this past June. I went through some difficulties in my life 2004-early 2006 so I never got a chance to dyno the car right after the headers . Last night the guys doing the dyno said the car felt much stronger then what it was reading and they do Mustangs all the time :p. Unfortnately the man died that ran the dyno I first had my car on so I cant take it back there . He was a master at tuning and had a great set up......ashame he died. I would very much like to take my car to the track but am afraid of people watching me and I'll be soooo nervous I'll screw something up
. I hope this coming spring to get up the courage to take it.....with my boyfriend there to help me. Maybe he can make everyone turn their backs when I go down . Anyway thanks again. LS1 Tech Stories
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From: Omaha, NE
I agree with 2002blackZ, always use the same dyno and proceedure for comparisons. One thing that I've stated many times before, any dyno who uses "standard correction" is giving you worthless numbers for comparison purposes pull to pull, not to mention for forum comparisons.
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From: England
Originally Posted by Flamin' bird
The dyno in 2003 was SAE. This recent one was STD. I didnt realize about the factor till last night. If that is the case then the numbers I had in 2003 in SAE would be higher? And now the STD #'s would be lower if they were SAE...and now my numbers are lower then before the headers??....correct?? Uggh if that's the case then something seriously is messed up I will get a stock MAF but I plan on installing an LS6 instake soon and then get it tuned so I guess I wont bother getting it dynoed before I do so
One another note...that day in 2003 when I had it dynoed most everyone was surprised it dynoed that high and thought it should be lower so I dont know. Everyone else that was there that day had their numbers be right on.
Uggh if that's the case then something seriously is messed up I will get a stock MAF but I plan on installing an LS6 instake soon and then get it tuned so I guess I wont bother getting it dynoed before I do soOne another note...that day in 2003 when I had it dynoed most everyone was surprised it dynoed that high and thought it should be lower so I dont know. Everyone else that was there that day had their numbers be right on.
nono for comparing results.But it's the SAE/STD thats likly a cause here.
SAE means it has been corrected to specific Society of Automtive Engineers standards. This removes any error caused by temps and such, so it really will have little bearing on if it's 50 degrees out or 90.
STD does NOT correct for this and gives you what the car is physically making at the exact moment. So from day to day or even hour to hour this will vary.
Example:
A car was dyno'd twice on the same dyno with the same mods and settings but on two different days.
In STD form there was over 20rwhp variance, but corrected to SAE it was less than 0.5rwhp variance.
So you can see it makes a MASSIVE difference.
If the dyno operator didn't explain this and didn't correct to SAE then it's just another example of so called professionals having absolutly no clue.
lol 
12.5:1 AFR is good, I would leave it alone. Moving to 13:1 won't mean diddly. Different dyno's, different days, I wouldn't worry about that. Also, not sure what changes you have had in fuel, here we now have ethanol that we didn't have before. One last thing I noticed in your first graph is you appear to have weak valve springs, there is a dip in the curve out at 5,700 that sure looks like spring surge. You may want to replace your valve springs.
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From: Omaha, NE
Quote, "SAE means it has been corrected to specific Society of Automtive Engineers standards."
Careful, there are different standards, as an example, the most common for chassis dynos is the SAE J1349, however some are using the SAE J607 which corrects to approx 5% higher then J1349.
Careful, there are different standards, as an example, the most common for chassis dynos is the SAE J1349, however some are using the SAE J607 which corrects to approx 5% higher then J1349.
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From: harrisburg, pa
i disagree with a few people here
12.5>13.3 AFR will make a BIG difference
Get a stock 01 up MAF on it
SAE to STD will make a 10rwhp difference easy depending on the conditions. Ive seen it personally.
Different dynos could be another 10rwhp
I could easily see 20-30rwhp here.. Ive never seen SLP headers perform as good as other brands either.
12.5>13.3 AFR will make a BIG difference
Get a stock 01 up MAF on it
SAE to STD will make a 10rwhp difference easy depending on the conditions. Ive seen it personally.
Different dynos could be another 10rwhp
I could easily see 20-30rwhp here.. Ive never seen SLP headers perform as good as other brands either.
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From: England
Originally Posted by dynocar
Quote, "SAE means it has been corrected to specific Society of Automtive Engineers standards."
Careful, there are different standards, as an example, the most common for chassis dynos is the SAE J1349, however some are using the SAE J607 which corrects to approx 5% higher then J1349.
Careful, there are different standards, as an example, the most common for chassis dynos is the SAE J1349, however some are using the SAE J607 which corrects to approx 5% higher then J1349.
I once heard of a dyno shop claiming a STOCK pre 01 Ls1 with only a catback was producing 409bhp (fllywheel)!
And no it wasn't an STS catback either
But yeah you are correct there are different SAE standards.
Thanks for all the replies and input...greatly appreciated. And I guess I should watch how I word stuff....I've been told that a few times 
Anyway I bought stock MAF ends and 02 sensors from two members here and then hopefully soon I'll get the LS6 intake installed whenever it gets here....patiently waiting. Also then hopefully in the early spring we'll make a trip down to CAM and get Jeff to dyno tune it 
.
The guy that did the initial dyno John Sealock of Woodbridge Dynotech was one of the best around as I stated before but my numbers did seem pretty high for the mods I had at the time. The guys that did it Monday night didnt even have a fan under the car like John did. Hopefully I'll have much better numbers next time...wish winter wasn't just around the corner. The agony of the wait to get to CAM
Anyway I bought stock MAF ends and 02 sensors from two members here and then hopefully soon I'll get the LS6 intake installed whenever it gets here....patiently waiting. Also then hopefully in the early spring we'll make a trip down to CAM and get Jeff to dyno tune it .The guy that did the initial dyno John Sealock of Woodbridge Dynotech was one of the best around as I stated before but my numbers did seem pretty high for the mods I had at the time. The guys that did it Monday night didnt even have a fan under the car like John did. Hopefully I'll have much better numbers next time...wish winter wasn't just around the corner. The agony of the wait to get to CAM
Originally Posted by dynocar
Quote, "The guys that did it Monday night didnt even have a fan under the car like John did."
The fan should be in front of the car, yes, be careful how you word things - just kidding.
The fan should be in front of the car, yes, be careful how you word things - just kidding.
Hehehehee
Yeah they didnt have any fans running at all for the first 3 runs. It was mid way through the 3rd they stopped and said they would let the car cool down then try to get some air going through. Apparently the fan that usually use was broke and they did some makeshift set up . They had a large fan on the ground sort of aiming up and then a fan sitting in the engine bay blowing down . TECH Addict
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From: England
Originally Posted by Flamin' bird
Hehehehee Yeah they didnt have any fans running at all for the first 3 runs. It was mid way through the 3rd they stopped and said they would let the car cool down then try to get some air going through. Apparently the fan that usually use was broke and they did some makeshift set up . They had a large fan on the ground sort of aiming up and then a fan sitting in the engine bay blowing down .
Yeah they didnt have any fans running at all for the first 3 runs. It was mid way through the 3rd they stopped and said they would let the car cool down then try to get some air going through. Apparently the fan that usually use was broke and they did some makeshift set up . They had a large fan on the ground sort of aiming up and then a fan sitting in the engine bay blowing down .and they should be trying to mimic running the car on the tarmac. So a 4th gear pull (1:1 ratio) to the red line means well over 100mph. Which is significant airflow.
Here's a dynoshop I know of here in the UK:
The Company has carried out a significant and major investment in acquiring a Dyno Dynamics full multi vehicle four wheel drive adjustable rolling road test facility incorporating the latest in dyno tuning from the worlds most well respected manufacturer of this type of specialist equipment.
Weston Performance are installing a 3600 brake horse power 4500 ftlb torque dyno dynamics four wheel drive rolling road facility with twin retarders and adjustable bed housed in a purpose built specially designed and engineered dyno cell within our own main facility in Solihull. JK4 M42
The cell has been designed using state of the art airflow and acoustics technology. Aerodynamics and Thermodynamics have also been applied to produce a cell capable of maintaining a consistent and controllable temperature throughout the testing process.
The cell has been designed to flow a sheet of air across the car at an adjustable rate of between 20,000- 60,000cfm with a velocity of 4ms this coupled with adjustable plenum technology will allow air to be flowed at varying rates and angles across the vehicle to simulate differing road conditions. Whilst the vehicle is being tested we have an additional 30,000 cfm radiator and intercooler fans, these are used to further simulate real road conditions and keep the vehicle at safe operating temperatures at all times during testing.
Weston Performance are installing a 3600 brake horse power 4500 ftlb torque dyno dynamics four wheel drive rolling road facility with twin retarders and adjustable bed housed in a purpose built specially designed and engineered dyno cell within our own main facility in Solihull. JK4 M42
The cell has been designed using state of the art airflow and acoustics technology. Aerodynamics and Thermodynamics have also been applied to produce a cell capable of maintaining a consistent and controllable temperature throughout the testing process.
The cell has been designed to flow a sheet of air across the car at an adjustable rate of between 20,000- 60,000cfm with a velocity of 4ms this coupled with adjustable plenum technology will allow air to be flowed at varying rates and angles across the vehicle to simulate differing road conditions. Whilst the vehicle is being tested we have an additional 30,000 cfm radiator and intercooler fans, these are used to further simulate real road conditions and keep the vehicle at safe operating temperatures at all times during testing.