ean611 Posted September 8, 2009 Share Posted September 8, 2009 Measured on a Dyno Dynamics unit @ Dent Sport Garage (www.dentsport.com) Before (Stage 2) http://i96.photobucket.com/albums/l177/ean611/IMAG0047.jpg After SPT intake + Heat shield + retune (Pull started slightly later, hence slightly lower torque peak, could have run another pass, but not worth it for time, overall torque curve was higher) http://i96.photobucket.com/albums/l177/ean611/dyno2.jpg Guess the SPT intake isn't so bad after all. Also, Matt @ DSG rocks. Link to comment Share on other sites More sharing options...
Guest LGT-NY Posted September 8, 2009 Share Posted September 8, 2009 Guess the SPT intake isn't so bad after all. No, it still is. Link to comment Share on other sites More sharing options...
ean611 Posted September 8, 2009 Author Share Posted September 8, 2009 LGT-NY, Just to ask, it's bad compared to what? I'm just looking at dyno charts. Link to comment Share on other sites More sharing options...
Guest LGT-NY Posted September 8, 2009 Share Posted September 8, 2009 It's an extremely inefficient design. Link to comment Share on other sites More sharing options...
ean611 Posted September 8, 2009 Author Share Posted September 8, 2009 LGT-NY: In your opinion, what design is better? Also, I'm curious to see dyno charts, as if there's something better, I'd love to see how much better it gets. Link to comment Share on other sites More sharing options...
ebondragon87 Posted September 9, 2009 Share Posted September 9, 2009 Great before and after by the op. Also, I'm curious to see dyno charts, as if there's something better, I'd love to see how much better it gets. I would be interested in seeing dyno sheets of other intakes as well. It's an extremely inefficient design. It’s not that bad of a design and yes I have read the thread about the SPT intake and Cobb's (I think) analysis of it. I have had and worked on alot of cars with intakes that had much worse designs and must say if you want an intake and don't want to have to worry about your warranty because alot of Subaru dealers are picky then its a good choice. But if you are worried that a bend in the pipe will cause such awful turbulence that your MAF will go haywire then buy a different intake. Just don't buy one with an oil style filter. I have had my SPT intake for almost 20k miles and never had a problem. I even monitored my MAF readings for a week just to see if it really changed that much. The MAF read properly at Idle, cruising, and heavy load. Just my 2 cents. Link to comment Share on other sites More sharing options...
Guest LGT-NY Posted September 9, 2009 Share Posted September 9, 2009 I had an SPT Intake for about 3 months. I was pulling IAT's in 120F range (In October). When you opened the hood, the "cast iron" piping was hot to the touch. I switched it out for an AEM CAI (And a new protune to match). In the sames conditions, I was pulling IAT's 40-50 degrees lower. Additionally, the thin aluminum design of the AEM retains MUCH less heat. Colder air means MOAR POWAHHHH!! Just my 2 cents. Link to comment Share on other sites More sharing options...
mwiener2 Posted September 9, 2009 Share Posted September 9, 2009 One dyno pull, then modify, then do another pull.... garbage. Your changes in HP are do to temp changes in the car/ engine/ dyno bay, not the CAI. edit: Just noticed the pulls were done on different days.... even more garbage. Your change in power is more than likely weather related or even how they strapped the car to the dyno. My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
ean611 Posted September 9, 2009 Author Share Posted September 9, 2009 One dyno pull, then modify, then do another pull.... garbage. Your changes in HP are do to temp changes in the car/ engine/ dyno bay, not the CAI. Based on that, how does one tune a car? If you do a dyno pull, data log, and change parameters based on that, then re-test, I don't see how that invalidates data. Based on this premise, there is no way to verify that if I change something in the engine, you see a change, even isolating other factors, such as using same dyno, same technician, and same indoor conditions. Dyno is Dyno Dynamics, Per Dent Sport Garage (www.dentsport.com), the dyno has been verified to read consistently with the same car on very different days. I'm not trying to start a flame war about intakes, I'm just putting out the data I have. EDIT: Car was re-tuned with SPT intake, this was not a bolt on and see what happens!! (bolt on and pull resulted in a loss of 3-5HP) Link to comment Share on other sites More sharing options...
ean611 Posted September 9, 2009 Author Share Posted September 9, 2009 LGT-NY: Just curious, did you use the heat shield? http://i96.photobucket.com/albums/l177/ean611/IMAG0049.jpg Link to comment Share on other sites More sharing options...
itsme Posted September 9, 2009 Share Posted September 9, 2009 I have a K&N typhoon and logs show that it flows more air then stock and it's consistent so it is pretty easy to tune. Racer X FMIC for '05-'09 LGTs, '08+ WRX and '10+ LGT,'14+ FXT, and '15+ WRX TMIC Racerxengineering.com Link to comment Share on other sites More sharing options...
Guest LGT-NY Posted September 9, 2009 Share Posted September 9, 2009 LGT-NY: Just curious, did you use the heat shield? Yes. That heat shield is bogus... Link to comment Share on other sites More sharing options...
ean611 Posted September 9, 2009 Author Share Posted September 9, 2009 LGT-NY. I just ran the entire configuration by the mechanical engineer on site here. (We do servers). He primarily deals with heat flow for our servers. Per conversation, I find it hard to believe that the heat shield is irrelevant. There will be some air flow around the heat shield, but the majority is coming from the fender wall. This will lower the air intake temperature. This is before you account for other pressure effects from air being sucked out of the fender wall. Also, @ 300CFM, if the SPT intake is 120F, you will see a max ~2 degree increase in air temperature flowing through that. Unless air is not flowing in the intake, the temperature delta from the temperature of the intake tube is negligible. Link to comment Share on other sites More sharing options...
Guest LGT-NY Posted September 9, 2009 Share Posted September 9, 2009 http://i211.photobucket.com/albums/bb93/bpotts1/peanuts_veil.jpg Link to comment Share on other sites More sharing options...
ean611 Posted September 9, 2009 Author Share Posted September 9, 2009 LGT-NY, I'm not trying to get into some kind of match defending the SPT intake, it was cheap and I figured I'd give it a shot. I'm just looking at the data. I would love to see other hard data from other intakes!! Link to comment Share on other sites More sharing options...
GTkansan Posted September 9, 2009 Share Posted September 9, 2009 I had an SPT Intake for about 3 months. I was pulling IAT's in 120F range (In October). When you opened the hood, the "cast iron" piping was hot to the touch. I switched it out for an AEM CAI (And a new protune to match). In the sames conditions, I was pulling IAT's 40-50 degrees lower. Additionally, the thin aluminum design of the AEM retains MUCH less heat. Colder air means MOAR POWAHHHH!! Just my 2 cents. the pipe 'retains' less heat obviously, there is less material. But the heat source is the under hood air. A thick chunk of iron (low thermal conductivity compared to aluminum) will block much more heat transfer than a thin piece of aluminum (heat flux through a metal is proportional to the thermal conductivity divided by the thickness). For the same underhood conditions, less heat will be transferred to the air entering the intake... Link to comment Share on other sites More sharing options...
ean611 Posted September 9, 2009 Author Share Posted September 9, 2009 the pipe 'retains' less heat obviously, there is less material. But the heat source is the under hood air. A thick chunk of iron (low thermal conductivity compared to aluminum) will block much more heat transfer than a thin piece of aluminum (heat flux through a metal is proportional to the thermal conductivity divided by the thickness). For the same underhood conditions, less heat will be transferred to the air entering the intake... Exactly. (Had a chat with some thermal engineers this afternoon on the subject) Link to comment Share on other sites More sharing options...
GTkansan Posted September 10, 2009 Share Posted September 10, 2009 Im glad they agree... since I am one as well... PhD in mechanical engineering with a specialty in heat and mass transport phenomena. Link to comment Share on other sites More sharing options...
mwiener2 Posted September 10, 2009 Share Posted September 10, 2009 If you did 3 pulls back to back and averaged them, then added the CAI and did 3 more pulls back to back and averaged them, then you might get a real result. There are literally hundreds of things that can throw a reading +- 15-20hp. If you take the car off and then back on the dyno, you can double the number of variables. The dyno uses air temp and humidity and whatnot to make calculations to correct the numbers. These are calculations, not recorded data. This is why some tuners prefer to use uncorrected or low correction numbers. They want to use real data and not calculated numbers. My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
ean611 Posted September 10, 2009 Author Share Posted September 10, 2009 mwiener2, Dent Sports Dyno is a "heartbreaker" per their own web site. They do not use major correction factors, and that "220" I pulled would probably be 260-280 on a Mustang or DynoJet Stock WRX pulls 140 on their Dyno Link to comment Share on other sites More sharing options...
KurtP Posted September 10, 2009 Share Posted September 10, 2009 hey cool before and after. You have to remember dude, around here and nasioc dyno testing an track times dont mean anything to anyone, and are regarded as useless. If you didnt dyno your car with and without the intake on the same day AT THE SAME TIME (yes, SIMULTANIOSLY) it will be considered a worthless test. The fact that you used the same dyno is irrelevant. There could be a 50, 60, maybe even 80hp difference by doing the dyno on a different day. The fact it would take you 30-45 minutes to install an intake means a before and after is useless too. Do you have any idea how much difference 30 minutes can make? People here head to the streets and bring pages and pages of spread sheets to talk shit about 5% gain in efficiency, 10deg difference in IAT, a whole 200rpm greater "spool" as if they make the difference between your car slamming your head through the headrest or sputtering and barely running. looking at your weather almanac for MA brings serious concerns to this test. peak temperature for the day varied about about .9 degrees. Average temperature for the day varied a WHOPPING 5 degrees. dude, 5 degrees can be like, 40whp on a stock car. The egg-heads crack me up sometimes. When I worked at a shop (non subaru) I was a beta tester for new engine software that came out. I had dozens/hundreds of pulls on a dyno and "road logs" across a span of a few months on my car. I dont think that minor weather variances ever accounted for more than a difference than 3hp except for when it was either extremely hot (above 85-90) or extremely cold in the dead of winter. Just because temperature changes, in this case maybe 5 degrees or whatever isnt going to make some huge difference. All the times i strapped my car down to a dyno, I never saw a change of 20 degrees or where i hooked up the straps the dyno(oh noes, i didnt use a scale to check the tension on the straps between days either!!) make a "15-20" whp difference. Dynoing my car the morning after a harvest moon didnt even vary it 15hp. While I will agree that doing more that one pull is better, i never saw back to back pulls make much difference until heat soak started to set in pretty good, which probably isnt really an issue here. the rule of thumb I usually went with was as long as the days were similar the 3-5 hp range of difference could be a "variance" but when you started getting up towards 10hp and it was a consistent gain (not a "spike") then you were starting to see a "gain". You know your car and your dyno and your shop. If you/they believe there was a gain from retuning with the intake, then there probably was. Can we complete the thread and have someone else chime in on how its an invalid pull because they started at a different rpm? extra points for adding the word "spool" at least three times. [/sarcasm] But, these are just my feelings. Many more with more time in subaru's will disagree than agree Link to comment Share on other sites More sharing options...
mwiener2 Posted September 10, 2009 Share Posted September 10, 2009 ^^ if you only had a 3-5hp difference between days then the dyno you were using was using correction factors My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
KurtP Posted September 10, 2009 Share Posted September 10, 2009 yeah I usually liked to have the CF set to around 1.85 or in that range. Gave the best results. Link to comment Share on other sites More sharing options...
mwiener2 Posted September 10, 2009 Share Posted September 10, 2009 I like to use a CF of 2 My Mods List (Updated 8/22/17) 2005 Outback FMT Running on Electrons Link to comment Share on other sites More sharing options...
KurtP Posted September 11, 2009 Share Posted September 11, 2009 yeah I had to use a correction factor of 2 if I hooked the tow strap to my trailing arm bar instead of my tow hook. It threw things off quite a bit when I did that. Link to comment Share on other sites More sharing options...
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