Dyno results with filter and cutout combinations
05-19-2012, 03:16 AM
#1
Dyno results with filter and cutout combinations
So I thought this was interesting enough to make a spreadsheet and pretty graphs about...
Went to the dyno yesterday, more for testing than an absolute number. I stayed on the same tune I drove an hour on to get there, very safe, ~11degrees of timing at WOT and fueling at 0.76 lambda. After I made some pulls with the 76 I was going to swap it out for the 80. Long story short, when it was torn down, it looked like the journal bearings were about gone because of too much heat in the turbine...most likely because I have been running such low timing. I also managed to melt a strap holding my axle down because my exhaust exits straight back. So it turns out low timing isnt such a "safe" thing after all. Fueling was spot on though; carbon buildup on the turbine looked perfect. I was running on approximately 25% E85 during the day. I didnt want too much e85 because I didnt want to run out of injector, but wanted enough to keep it safe. Meth was turned on for my last couple runs of the day to keep it safe.
I tried several combinations with my air filter and cutout to see if it made any difference, and it turns out to make a huge difference. My turbo has a 5.5" inlet, which I have a 90 degree adapter from 5.5" to 4" to a very large 4" filter on the end. I wasnt expecting much difference taking this off, maybe less than 10hp. On the exhaust side I have a 4" downpipe to a 4" cutout after the wasteagate, and the rest of the exhaust is 4" as well using a straight-through flo-pro muffler. I wasnt expecting any real difference with this, maybe 5hp, as I thought the 4" DP was plenty and just liked the sound. I kept the tune and wastegate settings exactly the same between runs. The numbers may seem a little low, but thats beside the point. The dyno was a Dyno Dynamics and I ran in 3rd gear with the converter locked.
Simply removing the air filter gave me 29hp and 16ft-lbs of torque. Additionally opening the cutout gave me another 42hp and 16ft-lbs of torque for a total gain of simply removing the filter and opening the cutout of 71hp and 32ft-lbs. That was very unexpected... Also opening the cutout allowed my boost controller to work much better and boost stayed constant the entire run instead of falling off at higher rpms.
At this point I suspected my intercooler was worse than I thought because I should have gain 100-150hp with 3lbs instead of the 58hp I saw. After these runs I swapped to the 80mm compressor while keeping the same turbine wheel and turbine housing. I had the compressor housing tapped so we could monitor pressure drop across the intercooler as well
Running the same timing and boost controller settings between the 76 and 80mm with the filter off and cutout closed, I saw a 43hp gain and a 13ftlb gain. At 9psi of boost I was seeing about 13psi at the compressor housing, so already the intercooler was costing me 4psi.
Adding 2.5deg and 3.5psi gained me 102hp and 125ftlbs, however compressor pressure was 19.5psi while manifold pressure was 12.5psi, for an intercooler loss of 7psi. Adding another 1.5 degrees of timing actually cost me some peak torque and the same power, so I backed it down a bit.
For the last run I opened up the cutout and added some timing up top while pulling some at peak torque to prevent knock and try to extend the torque curve. I also increased boost 2.5psi to the level I ultimately wanted to settle around with my setup, about 16psi. This increased power output by 87hp and 46ftlbs to my highest of the day making 707hp at 5560rpm and 683ftlbs at 5300rpm. However, while manifold pressure held steady at 16psi, the pressure at the compressor housing was 24psi for a loss of 8psi through the intercooler. I also saw intake temps rise from 90F to 167F in ~12 seconds with meth spraying.
I was hoping to break 800hp, but it is obvious my intercooler is far too small for my setup, but even I was surprised how much it is holding me back. I actually ordered a better one at the beginning of the week, but it didnt make it here in time. My current one is a 24x12x3.5" core from ebay. The one I have coming is a 27x12x4" core from CXRacing. They claim it is good for 1000+hp, so I guess we will see. I have enough turbo and engine to push me well past 800, now I just need an intercooler that will get out of the way!
I uploaded the spreadsheet with all the data if anyone cares to look at it. Note there are 2 pages.
Cliff notes: Take off air filter, open cutout, and get a good intercooler!
Went to the dyno yesterday, more for testing than an absolute number. I stayed on the same tune I drove an hour on to get there, very safe, ~11degrees of timing at WOT and fueling at 0.76 lambda. After I made some pulls with the 76 I was going to swap it out for the 80. Long story short, when it was torn down, it looked like the journal bearings were about gone because of too much heat in the turbine...most likely because I have been running such low timing. I also managed to melt a strap holding my axle down because my exhaust exits straight back. So it turns out low timing isnt such a "safe" thing after all. Fueling was spot on though; carbon buildup on the turbine looked perfect. I was running on approximately 25% E85 during the day. I didnt want too much e85 because I didnt want to run out of injector, but wanted enough to keep it safe. Meth was turned on for my last couple runs of the day to keep it safe.
I tried several combinations with my air filter and cutout to see if it made any difference, and it turns out to make a huge difference. My turbo has a 5.5" inlet, which I have a 90 degree adapter from 5.5" to 4" to a very large 4" filter on the end. I wasnt expecting much difference taking this off, maybe less than 10hp. On the exhaust side I have a 4" downpipe to a 4" cutout after the wasteagate, and the rest of the exhaust is 4" as well using a straight-through flo-pro muffler. I wasnt expecting any real difference with this, maybe 5hp, as I thought the 4" DP was plenty and just liked the sound. I kept the tune and wastegate settings exactly the same between runs. The numbers may seem a little low, but thats beside the point. The dyno was a Dyno Dynamics and I ran in 3rd gear with the converter locked.
Simply removing the air filter gave me 29hp and 16ft-lbs of torque. Additionally opening the cutout gave me another 42hp and 16ft-lbs of torque for a total gain of simply removing the filter and opening the cutout of 71hp and 32ft-lbs. That was very unexpected... Also opening the cutout allowed my boost controller to work much better and boost stayed constant the entire run instead of falling off at higher rpms.
At this point I suspected my intercooler was worse than I thought because I should have gain 100-150hp with 3lbs instead of the 58hp I saw. After these runs I swapped to the 80mm compressor while keeping the same turbine wheel and turbine housing. I had the compressor housing tapped so we could monitor pressure drop across the intercooler as well
Running the same timing and boost controller settings between the 76 and 80mm with the filter off and cutout closed, I saw a 43hp gain and a 13ftlb gain. At 9psi of boost I was seeing about 13psi at the compressor housing, so already the intercooler was costing me 4psi.
Adding 2.5deg and 3.5psi gained me 102hp and 125ftlbs, however compressor pressure was 19.5psi while manifold pressure was 12.5psi, for an intercooler loss of 7psi. Adding another 1.5 degrees of timing actually cost me some peak torque and the same power, so I backed it down a bit.
For the last run I opened up the cutout and added some timing up top while pulling some at peak torque to prevent knock and try to extend the torque curve. I also increased boost 2.5psi to the level I ultimately wanted to settle around with my setup, about 16psi. This increased power output by 87hp and 46ftlbs to my highest of the day making 707hp at 5560rpm and 683ftlbs at 5300rpm. However, while manifold pressure held steady at 16psi, the pressure at the compressor housing was 24psi for a loss of 8psi through the intercooler. I also saw intake temps rise from 90F to 167F in ~12 seconds with meth spraying.
I was hoping to break 800hp, but it is obvious my intercooler is far too small for my setup, but even I was surprised how much it is holding me back. I actually ordered a better one at the beginning of the week, but it didnt make it here in time. My current one is a 24x12x3.5" core from ebay. The one I have coming is a 27x12x4" core from CXRacing. They claim it is good for 1000+hp, so I guess we will see. I have enough turbo and engine to push me well past 800, now I just need an intercooler that will get out of the way!
I uploaded the spreadsheet with all the data if anyone cares to look at it. Note there are 2 pages.
Cliff notes: Take off air filter, open cutout, and get a good intercooler!
05-19-2012, 03:43 AM
#2
Some good info right there and not bad #'s considering the I/C drop and dyno. Those dyno dynamics read really low from what I've seen. I went mid 10's@127mph with 714HP on a dyno dynamics. After seeing the gains from air filter, cutout, and I/C restriction it has me wondering how much I'm getting screwed lol. I'm running same elbow on my GT76, along with 4'' dp, and then necks down to 3.5'' exhaust pipe with 3.5'' muffler. Then running thru a 24x10x3 cheap I/C as well supposed to be rated for 500hp. I have always ran thru full exh and muffler never tried it open.
05-19-2012, 06:30 AM
#3
Damn good info Bud!!!!!
That is a stout asskicking setup you have man!
What brand of cutout do you have? I want to add one to my setup and see if i gain any. My times and numbers were all thru a shitty summit turbo muffler and small intake tube (3.5) . Even though your turbo this is great info i think will help us all.
That is a stout asskicking setup you have man!
What brand of cutout do you have? I want to add one to my setup and see if i gain any. My times and numbers were all thru a shitty summit turbo muffler and small intake tube (3.5) . Even though your turbo this is great info i think will help us all.
05-19-2012, 07:05 AM
#4
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Richard that's impressive!! Congrats on getting your truck running so good!
Makes me wonder what gains mine would have seen with no air filter, it was really small. We'll have to get spoolin to do some testing
.
What dyno did you go to? I'm gonna have to go to Holiday and watch you spank Mitch
Makes me wonder what gains mine would have seen with no air filter, it was really small. We'll have to get spoolin to do some testing
.What dyno did you go to? I'm gonna have to go to Holiday and watch you spank Mitch
When I get my truck issues sorted out! 
