580whp Subaru
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*Big Schpellar*
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580whp Subaru
Originally Posted by PDXTuning
At our little open house this weekend we decided to throw Tim’s STI with the GT37 on the dyno to see what it would do. As some of you might remember, I ran a GT37/GT40 hybrid last year, which used a GPMoto built header/uppipe, downpipe, and Ti Exhaust. Since I am going to use the full GT40 on the H6, I split apart the 3740, and mated the parts back together with the 4037 to get back the original GT37 and GT40 turbo. Since I’m not going to use the GT37, we put it along with the header/uppipe/downpipe into Tim's STI to see what it would do.
Tim had a COBB protuner pump gas map, so we took the fuel map and leaned it out real quick, and added a bit of timing, threw in some C16 and turned up the boost. Both the pump fuel tune and the C-16 tune were done with Access ECU protuner software. The tune is not optimized due to lack ot time but C16 is very forgiving anyways. I was not really sure what to expect. This has a 1.12 AR hot side and is twin scroll. It is not a ball bearing turbo, and as such is pretty inexpensive. You can rebuild each piece individually, and swap in different wheels and housings.
Tim hasn’t gotten around to getting his DTEC installed, so he threw a manual boost controller on it, which worked. The only downside of the manual is that it doesn’t provide positive pressure to the second port on the external, and it really doesn’t hold the boost flat all the way to redline. No matter what level (18psi-32psi), the boost always peaks a bit more, then rolls a bit to redline. Certainly we will get the DTEC on there and see what we can do.
At about 32-33psi, falling to 29psi at redline, it peaked a bit shy of 580whp uncorrected, 596whp corrected. Take a look at the plots:
The purple is the GT37, and the yellow is the FP Red Tim had on before, also on C16.
Non corrected graphs: (meaningful)
SAE corrected graphs: (meaningless)
[img]http://www.pdxtuning.com/nasioc/Tim37RedSAE.jpg[/img]
That is 564 lb-ft ( 578 lb-ft corr ) of Torque. That’s pretty snappy. The twin scroll helps the spool a bit, but it is still laggy as hell. Once the boost rolls in, it feels pretty scary fast, especially on street tires. Right at the torque peak the tires just rip loose in 4th gear. I’m sure it will be fun to drag race, and Tim is looking forward to the rain going away.
A couple of other observations:
The car still has the single plate Exede Hypersingle clutch, which is at a state of complete failure. On the dyno, every other pull it would break completely free, and if I ran right away again, while the clutch was still hot, it would hold for a pull. On the street, 4th held every other pull,and 5th breaks free right away. Tim has a Twin plate sitting on the shelf, but we just have not had time to get it in there.
This was using a new prototype blow-thru maf we made, almost 3.5” diameter with some custom placement and design, and it didn’t hit 5.0Vs. Very happy about that! This was using the Access Port with the ProTune, MAF all the way.
The mods are the usual: Perrin FMIC and Perrin Injectors, the turbokit, the block has CP pistons that we slapped in, plus we balanced the motor before reassembly. Stock heads and cams of course. No WI running right now.
These CPs are VERY loose, perhaps on the 4 thou side. As a result, when the car is cold, it smokes quite a bit, and if you jump on it much at all while cold, it burns oil. Once the pistons get hot, very hot, the motor runs perfectly. We did perhaps 10 pulls at 580whp, all in a row, no real delay, and the motor purrs like a kitten. Like the CP guys say, they are race pistons.
When driving, the most noticeable thing other then the peak torque is the feeling that the HP stays pretty flat once on. The larger turbine side shows no signs of letting up. Since this is the stock valvetrain, we didn’t really push it above 7k, but from what I can tell, it looks like the HP will keep flat for a while longer.
Since upgrade parts are so cheap, we are going to throw on the GT4088 compressor wheel and compressor housing and run it, just to see how the GT4088 compressor compares.
I posted a while back a few compressor maps, so you can see how the GT37 compares to the GT35R. Have a look.
Tim had a COBB protuner pump gas map, so we took the fuel map and leaned it out real quick, and added a bit of timing, threw in some C16 and turned up the boost. Both the pump fuel tune and the C-16 tune were done with Access ECU protuner software. The tune is not optimized due to lack ot time but C16 is very forgiving anyways. I was not really sure what to expect. This has a 1.12 AR hot side and is twin scroll. It is not a ball bearing turbo, and as such is pretty inexpensive. You can rebuild each piece individually, and swap in different wheels and housings.
Tim hasn’t gotten around to getting his DTEC installed, so he threw a manual boost controller on it, which worked. The only downside of the manual is that it doesn’t provide positive pressure to the second port on the external, and it really doesn’t hold the boost flat all the way to redline. No matter what level (18psi-32psi), the boost always peaks a bit more, then rolls a bit to redline. Certainly we will get the DTEC on there and see what we can do.
At about 32-33psi, falling to 29psi at redline, it peaked a bit shy of 580whp uncorrected, 596whp corrected. Take a look at the plots:
The purple is the GT37, and the yellow is the FP Red Tim had on before, also on C16.
Non corrected graphs: (meaningful)
SAE corrected graphs: (meaningless)
[img]http://www.pdxtuning.com/nasioc/Tim37RedSAE.jpg[/img]
That is 564 lb-ft ( 578 lb-ft corr ) of Torque. That’s pretty snappy. The twin scroll helps the spool a bit, but it is still laggy as hell. Once the boost rolls in, it feels pretty scary fast, especially on street tires. Right at the torque peak the tires just rip loose in 4th gear. I’m sure it will be fun to drag race, and Tim is looking forward to the rain going away.
A couple of other observations:
The car still has the single plate Exede Hypersingle clutch, which is at a state of complete failure. On the dyno, every other pull it would break completely free, and if I ran right away again, while the clutch was still hot, it would hold for a pull. On the street, 4th held every other pull,and 5th breaks free right away. Tim has a Twin plate sitting on the shelf, but we just have not had time to get it in there.
This was using a new prototype blow-thru maf we made, almost 3.5” diameter with some custom placement and design, and it didn’t hit 5.0Vs. Very happy about that! This was using the Access Port with the ProTune, MAF all the way.
The mods are the usual: Perrin FMIC and Perrin Injectors, the turbokit, the block has CP pistons that we slapped in, plus we balanced the motor before reassembly. Stock heads and cams of course. No WI running right now.
These CPs are VERY loose, perhaps on the 4 thou side. As a result, when the car is cold, it smokes quite a bit, and if you jump on it much at all while cold, it burns oil. Once the pistons get hot, very hot, the motor runs perfectly. We did perhaps 10 pulls at 580whp, all in a row, no real delay, and the motor purrs like a kitten. Like the CP guys say, they are race pistons.
When driving, the most noticeable thing other then the peak torque is the feeling that the HP stays pretty flat once on. The larger turbine side shows no signs of letting up. Since this is the stock valvetrain, we didn’t really push it above 7k, but from what I can tell, it looks like the HP will keep flat for a while longer.
Since upgrade parts are so cheap, we are going to throw on the GT4088 compressor wheel and compressor housing and run it, just to see how the GT4088 compressor compares.
I posted a while back a few compressor maps, so you can see how the GT37 compares to the GT35R. Have a look.
http://forums.nasioc.com/forums/show...9#post13395029
was really cool to watch. when Tim gets the DTEK installed he will hit 600WHP easy
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