SLP Dyno Days
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From: Vancouver,[KITSILANO].B.C. Canada *WestCoast*
If I were close I would take advantage of it....with a tour that would be interesting....and a certificate of the pulls from SLP as well... 
Originally Posted by NJSPDER
how does one eliminate knock without tuning? only thing i can think of is to reduce the load imposed by the dyno, which would lead to wildly inaccurate numbers.
is there another method to reduce knock during/between pulls that i am not aware of?
is there another method to reduce knock during/between pulls that i am not aware of?
Many times vehicles are mod’d without change of thermostat or fan control, which causes the engine coolant temp to get higher then optimal while on the dyno. We have the ability on most vehicles to turn the fans on manually to keep the engine cool during testing. This also comes into play on stock cars where the fan settings for the high fans are above 220 degrees F. Hot motors = Knock Retard = False HP #'s. If anyone has this issue we will take care of it while testing.
Sometimes aftermarket exhaust systems not properly installed will cause false knock retard. If this is an issue we have the ability to fix that problem as well.
Sometimes low octane gas is an issue. If the tank is empty enough we have 93 octane on site where we can put in 5-10 gallons to reduce or eliminate knock.
Hot intake temperatures can also cause knock retard. (Heat Soak) Another reason for not performing quick, in and out dyno days. As running a vehicle hard on the dyno will increase IAT to undesirable levels. This needs to be monitored and time needs to be taken between pulls if necessary.
High cylinder head temperatures on long pulls will also induce knock. A vehicle that takes 20+ seconds to reach Rev Limit in 1:1 gear will have very high CHT when the test is over. Time needs to be taken, and sometimes vehice shutdown after cooldown, needs to be completed to get the cylinder head temperatures down again.
If a customer happens to come to SLP Dyno Day with their vehicle and a handheld programmer such as a diablo unit and they have a knock problem = can not get knock retard to "0" during testing we will use the handheld unit to remove a bit of timing to remove the knock if their timing is set to high. The opposite is true for A/F. If a customer has a handheld programmer such as a diablo unit and they have a lean condition causing knock we will add fuel using the handheld. As this is a dyno day with 12 cars and custom tuning takes time, these are the only changes we will make on this day in regards to tuning.
I can go on and on as to why vehicles may knock while being tested. I can tell you that if it is anything we can help on the dyno, we will take care of it.
As stated on the dyno day info page. These are inertia tests = how fast a vehicle can spin up a known, measured and accurate mass. These are not control load tests, which can become less accurate if not performed correctly as you are slowing the engine down by introducing an outside load and another variable into the equation.
edit: SLP has the ability to perform load control tests, but the standard is the inertia test. (There is more to the equation then just the mass.
) This way you can compare when performing a test on a dyno jet ect....I hope this answers your question.
Thanks
Hank
Last edited by SLPPower; Feb 19, 2007 at 04:43 PM.
I am confused as to why you would put a wideband O2 sensor after a catalytic converter?
The job of a catalytic converter is to burn off any residual hydro-carbons post combustion proccess in order to reduce tailpipe emissions. During the cat 'burn off' you will be using up more oxygen, hence indicating a lean condition, which is all the computer looks for from the rear O2 sensors.
Maybe I'm missing something, but everyone (including gasoline companies) place wideband O2 sensors in from of the catalytic converters in order to get true, post combustion readings, at least that's the way we did it at Sunoco when I was a research chemist in the emmisions/race fuel devision.
The job of a catalytic converter is to burn off any residual hydro-carbons post combustion proccess in order to reduce tailpipe emissions. During the cat 'burn off' you will be using up more oxygen, hence indicating a lean condition, which is all the computer looks for from the rear O2 sensors.
Maybe I'm missing something, but everyone (including gasoline companies) place wideband O2 sensors in from of the catalytic converters in order to get true, post combustion readings, at least that's the way we did it at Sunoco when I was a research chemist in the emmisions/race fuel devision.
Originally Posted by The Alchemist
I am confused as to why you would put a wideband O2 sensor after a catalytic converter?
The job of a catalytic converter is to burn off any residual hydro-carbons post combustion proccess in order to reduce tailpipe emissions. During the cat 'burn off' you will be using up more oxygen, hence indicating a lean condition, which is all the computer looks for from the rear O2 sensors.
Maybe I'm missing something, but everyone (including gasoline companies) place wideband O2 sensors in from of the catalytic converters in order to get true, post combustion readings, at least that's the way we did it at Sunoco when I was a research chemist in the emmisions/race fuel devision.
The job of a catalytic converter is to burn off any residual hydro-carbons post combustion proccess in order to reduce tailpipe emissions. During the cat 'burn off' you will be using up more oxygen, hence indicating a lean condition, which is all the computer looks for from the rear O2 sensors.
Maybe I'm missing something, but everyone (including gasoline companies) place wideband O2 sensors in from of the catalytic converters in order to get true, post combustion readings, at least that's the way we did it at Sunoco when I was a research chemist in the emmisions/race fuel devision.
The most true and accurate way to record Air Fuel for a performance engine is to record each cylinder in the manifold or header primaries. Obviously this requires custom headers or manifolds for each vehicle, which is realistic for engine dyno testing but not for chassis dyno single day testing.
edit: The position and angle of a wideband sensor is also very important when installing in an exhaust system. If you try and install a wideband in a spot that is obtainable because one would not remove the exhaust system pre cat, you will get false readings as well.
Thanks
Hank
Last edited by SLPPower; Feb 20, 2007 at 10:59 AM.
Originally Posted by The Alchemist
I am confused as to why you would put a wideband O2 sensor after a catalytic converter?
The job of a catalytic converter is to burn off any residual hydro-carbons post combustion proccess in order to reduce tailpipe emissions. During the cat 'burn off' you will be using up more oxygen, hence indicating a lean condition, which is all the computer looks for from the rear O2 sensors.
Maybe I'm missing something, but everyone (including gasoline companies) place wideband O2 sensors in from of the catalytic converters in order to get true, post combustion readings, at least that's the way we did it at Sunoco when I was a research chemist in the emmisions/race fuel devision.
The job of a catalytic converter is to burn off any residual hydro-carbons post combustion proccess in order to reduce tailpipe emissions. During the cat 'burn off' you will be using up more oxygen, hence indicating a lean condition, which is all the computer looks for from the rear O2 sensors.
Maybe I'm missing something, but everyone (including gasoline companies) place wideband O2 sensors in from of the catalytic converters in order to get true, post combustion readings, at least that's the way we did it at Sunoco when I was a research chemist in the emmisions/race fuel devision.
Thanks
Hank
I for one would think it would be awsome if you guys at SLP started the SLP day at E town again. I wouldnt mind paying what it cost to race to pay you guys at slp for the day again... I would love to do it again. Maybe more people would like to add to that
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Originally Posted by SLPPower
Many times vehicles are mod’d without change of thermostat or fan control, which causes the engine coolant temp to get higher then optimal while on the dyno. We have the ability on most vehicles to turn the fans on manually to keep the engine cool during testing. This also comes into play on stock cars where the fan settings for the high fans are above 220 degrees F. Hot motors = Knock Retard = False HP #'s. If anyone has this issue we will take care of it while testing.
Sometimes aftermarket exhaust systems not properly installed will cause false knock retard. If this is an issue we have the ability to fix that problem as well.
Sometimes low octane gas is an issue. If the tank is empty enough we have 93 octane on site where we can put in 5-10 gallons to reduce or eliminate knock.
Hot intake temperatures can also cause knock retard. (Heat Soak) Another reason for not performing quick, in and out dyno days. As running a vehicle hard on the dyno will increase IAT to undesirable levels. This needs to be monitored and time needs to be taken between pulls if necessary.
High cylinder head temperatures on long pulls will also induce knock. A vehicle that takes 20+ seconds to reach Rev Limit in 1:1 gear will have very high CHT when the test is over. Time needs to be taken, and sometimes vehice shutdown after cooldown, needs to be completed to get the cylinder head temperatures down again.
If a customer happens to come to SLP Dyno Day with their vehicle and a handheld programmer such as a diablo unit and they have a knock problem = can not get knock retard to "0" during testing we will use the handheld unit to remove a bit of timing to remove the knock if their timing is set to high. The opposite is true for A/F. If a customer has a handheld programmer such as a diablo unit and they have a lean condition causing knock we will add fuel using the handheld. As this is a dyno day with 12 cars and custom tuning takes time, these are the only changes we will make on this day in regards to tuning.
I can go on and on as to why vehicles may knock while being tested. I can tell you that if it is anything we can help on the dyno, we will take care of it.
As stated on the dyno day info page. These are inertia tests = how fast a vehicle can spin up a known, measured and accurate mass. These are not control load tests, which can become less accurate if not performed correctly as you are slowing the engine down by introducing an outside load and another variable into the equation.
edit: SLP has the ability to perform load control tests, but the standard is the inertia test. (There is more to the equation then just the mass. ) This way you can compare when performing a test on a dyno jet ect....
I hope this answers your question.
Thanks
Hank
Sometimes aftermarket exhaust systems not properly installed will cause false knock retard. If this is an issue we have the ability to fix that problem as well.
Sometimes low octane gas is an issue. If the tank is empty enough we have 93 octane on site where we can put in 5-10 gallons to reduce or eliminate knock.
Hot intake temperatures can also cause knock retard. (Heat Soak) Another reason for not performing quick, in and out dyno days. As running a vehicle hard on the dyno will increase IAT to undesirable levels. This needs to be monitored and time needs to be taken between pulls if necessary.
High cylinder head temperatures on long pulls will also induce knock. A vehicle that takes 20+ seconds to reach Rev Limit in 1:1 gear will have very high CHT when the test is over. Time needs to be taken, and sometimes vehice shutdown after cooldown, needs to be completed to get the cylinder head temperatures down again.
If a customer happens to come to SLP Dyno Day with their vehicle and a handheld programmer such as a diablo unit and they have a knock problem = can not get knock retard to "0" during testing we will use the handheld unit to remove a bit of timing to remove the knock if their timing is set to high. The opposite is true for A/F. If a customer has a handheld programmer such as a diablo unit and they have a lean condition causing knock we will add fuel using the handheld. As this is a dyno day with 12 cars and custom tuning takes time, these are the only changes we will make on this day in regards to tuning.
I can go on and on as to why vehicles may knock while being tested. I can tell you that if it is anything we can help on the dyno, we will take care of it.
As stated on the dyno day info page. These are inertia tests = how fast a vehicle can spin up a known, measured and accurate mass. These are not control load tests, which can become less accurate if not performed correctly as you are slowing the engine down by introducing an outside load and another variable into the equation.
edit: SLP has the ability to perform load control tests, but the standard is the inertia test. (There is more to the equation then just the mass.
) This way you can compare when performing a test on a dyno jet ect....I hope this answers your question.
Thanks
Hank
i also have to wonder what kind of a car can't maintain operating temperature with a water pump and a fan. if there is knock present when the coolant is at operating temp, that would be a tuning issue. waiting around for the car to cool off enough to find a temperature that doesn't knock as much would not result in any more accurate of a number for the owner of the car.
i know how dyno's work and i have been around many of them before. with your explanation i am still nto seeing anyting that would lead me to believe the resutl would be any more accurate than a normal dyno day, just the opposite in fact since you are controlling other factors to get the result you want instead of the result the car gives.
after thinking about several responses, all of which involve bashing slp- i have decided to simply say that i have NOTHING nice to say about slp, their prices, their products, and their customer service.
no matter how it is cut, 165$ IS a ripoff for a couple dyno pulls- but i don't blame SLP, if suckers will pay it why not charge it? guess the certificate makes it ALL worth it. you get the HONOR of dyno'ing at slp...
no matter how it is cut, 165$ IS a ripoff for a couple dyno pulls- but i don't blame SLP, if suckers will pay it why not charge it? guess the certificate makes it ALL worth it. you get the HONOR of dyno'ing at slp...
Originally Posted by NJSPDER
that doesn't really clear up much. you said there is no tuning before, now in this you say they can tune. which is it?
i also have to wonder what kind of a car can't maintain operating temperature with a water pump and a fan. if there is knock present when the coolant is at operating temp, that would be a tuning issue. waiting around for the car to cool off enough to find a temperature that doesn't knock as much would not result in any more accurate of a number for the owner of the car.
i know how dyno's work and i have been around many of them before. with your explanation i am still nto seeing anyting that would lead me to believe the resutl would be any more accurate than a normal dyno day, just the opposite in fact since you are controlling other factors to get the result you want instead of the result the car gives.
i also have to wonder what kind of a car can't maintain operating temperature with a water pump and a fan. if there is knock present when the coolant is at operating temp, that would be a tuning issue. waiting around for the car to cool off enough to find a temperature that doesn't knock as much would not result in any more accurate of a number for the owner of the car.
i know how dyno's work and i have been around many of them before. with your explanation i am still nto seeing anyting that would lead me to believe the resutl would be any more accurate than a normal dyno day, just the opposite in fact since you are controlling other factors to get the result you want instead of the result the car gives.
I was also answering a question as to how knock becomes present on a dyno.
If you are familiar with dyno operation then you can understand how each scenario that I explained can lead to knock. And you can understand the scenario below:
There is a major difference between normal running operating temp while a vehicle is in normal operating conditions (ie. Moving on the street) and operating temp while sitting still on a dyno. Allowing the fans to come on and stay on at a higher rate with a fan control switch (not a tune), IF NEEDED, allows for a more consistent, steady and accurate "real life" temperature. While your vehicle is traveling down the street ambient air travels across your radiator to cool your engine, this does not occur while on a dyno. While we are setup at SLP to create 30+MPH cross drafts in the dyno, this is still not always enough to keep the vehicle's engine coolant temp at a consistent "real life" temperature. This obviously is dependent on the testing day's ambient air temperature. For example, when you sit in traffic or at a traffic light for an extended period of time your engine's fans will come on at various temps depending on the tune, stock or mod. We do not want to test a vehicle that is operating at 210 degrees at the start of a pull because the fans will not come on until 220. This will happen on a stock thermostat and stock tune vehicle on even not so hot days. The idea is to keep the coolant temp consistent through each and every pull while on the dyno not allow the vehicles PCM to let the engine temp rise and fall by turning the fans off and on. This will produce inaccurate results, NOT accurate results. We must control and stabilize the ECT. So no, we are not controlling factors that will get the results we want, but the correct results and running conditions the vehicle will see while moving on the street, not sitting still at a light or in traffic.
edit: Additionally, if one does not keep the ECT the same for each pull it is very possible that you will get different WOT ignition timing as many times ignition timing can be added or removed based on ECT. IF you are on the edge a column in the PCM's table where it will take away 2 or 4 degrees timing and you allow the temp to rise and fall you will get different dyno numbers EVERY time, this is VERY INACCURATE and gives VERY UNTRUE dyno numbers. Which leads me to why providing customers with ALL PCM data on test day will help them when they test more parts on different dynos on another day.
doube edit: There are hundreds of ways that a late model EFI vehicle can become inaccurate while on the dyno. Knock or no Knock. Dyno testing is not just about the dyno. Please stop by on dyno day and I can give you a brief rundown and examples, as well as show you how the PCM corrects for changing IAT and ECT. Please come by at the end of the day, and when we are finished I will be more then happy to go over testing procedures with you.
Thanks
Hank
Last edited by SLPPower; Feb 25, 2007 at 11:01 PM.
Originally Posted by sleeperstyle
after thinking about several responses, all of which involve bashing slp- i have decided to simply say that i have NOTHING nice to say about slp, their prices, their products, and their customer service.
no matter how it is cut, 165$ IS a ripoff for a couple dyno pulls- but i don't blame SLP, if suckers will pay it why not charge it? guess the certificate makes it ALL worth it. you get the HONOR of dyno'ing at slp...
no matter how it is cut, 165$ IS a ripoff for a couple dyno pulls- but i don't blame SLP, if suckers will pay it why not charge it? guess the certificate makes it ALL worth it. you get the HONOR of dyno'ing at slp...
Hank
Originally Posted by SLPPower
Please PM me your PH# or email so that we can get in touch so that I can find out the issues you have had with any SLP product. I want to help. Also please make me aware of any poor customer service you might have encountered. I prefer to do this over the phone as I can help more swiftly then going back and forth on LS1 Tech. Not trying to hide anything, you can obviously post away after we talk. THANKS
Hank
Hank
I will say however that I recieved some, what I feel, good service from SLP regarding the purchase of a vette exhaust. I asked what type of muffler was used in a particular axle back because I was concerned with how loud it would be on my tweeked stroker. I was told that would be way too loud on my car. So, although I didn't get the intelligent answer I was looking for, I ultimately got the info I needed to make a purchase.
In case that's not enough, I called customer service because an x pipe I bought was missing hardware, and was not clear on installation issues on this particular car. I was told that on a 2004 car it must be a problem and they did not have any 2004 cars yet to check. When I asked what they were going to do about it, I was told to pack the parts up, pay to ship them back, and restock. I really just wanted the additional hardware. I was then told to basically send it back or deal with it on my own.
I don't even bother anymore and I live 20 min from the place.
Originally Posted by AintQik
Well, while we're at it I've had horrible customer service from a guy named "Joey" trying to spend over $4k. I'm not asking for anybody to kiss my *** over $4k but a little courtesy and professionalism would be nice.
I will say however that I recieved some, what I feel, good service from SLP regarding the purchase of a vette exhaust. I asked what type of muffler was used in a particular axle back because I was concerned with how loud it would be on my tweeked stroker. I was told that would be way too loud on my car. So, although I didn't get the intelligent answer I was looking for, I ultimately got the info I needed to make a purchase.
In case that's not enough, I called customer service because an x pipe I bought was missing hardware, and was not clear on installation issues on this particular car. I was told that on a 2004 car it must be a problem and they did not have any 2004 cars yet to check. When I asked what they were going to do about it, I was told to pack the parts up, pay to ship them back, and restock. I really just wanted the additional hardware. I was then told to basically send it back or deal with it on my own.
I don't even bother anymore and I live 20 min from the place.
I will say however that I recieved some, what I feel, good service from SLP regarding the purchase of a vette exhaust. I asked what type of muffler was used in a particular axle back because I was concerned with how loud it would be on my tweeked stroker. I was told that would be way too loud on my car. So, although I didn't get the intelligent answer I was looking for, I ultimately got the info I needed to make a purchase.
In case that's not enough, I called customer service because an x pipe I bought was missing hardware, and was not clear on installation issues on this particular car. I was told that on a 2004 car it must be a problem and they did not have any 2004 cars yet to check. When I asked what they were going to do about it, I was told to pack the parts up, pay to ship them back, and restock. I really just wanted the additional hardware. I was then told to basically send it back or deal with it on my own.
I don't even bother anymore and I live 20 min from the place.
I appologize for the bad service and I will make sure this gets taken care of.
I look forward to speaking with you.
Thanks
Hank
After talking with Hank it would be fair to say that SLP is making some changes and is genuinely concerned with customer feedback and opinion now. That's great to hear and I look forward seeing how SLP turns out.
Originally Posted by AintQik
After talking with Hank it would be fair to say that SLP is making some changes and is genuinely concerned with customer feedback and opinion now. That's great to hear and I look forward seeing how SLP turns out.