blackobxt Posted July 30, 2021 Share Posted July 30, 2021 So my tune is in the final process and as I’ve stated in a previous post, it really feels like it leaves a lot to be desired but I’ve also thought it was in my head. I just got back from visiting wyoming and my friend who owns my old 05 sti let me borrow it for the week and I immediately knew I wasn’t wrong about outback feeling like a dog. The sti is a pretty basic stage 2 setup, and all around feels smoother and snappier and waaaay more powerful even with the stock turbo. I started to worry when my tuner was expressing concerns about by spool times not peaking till 4k. Is the 16g the issue? Should I have gone with the vf52? My setup is: Bnr16g Invidia catless up pipe Invidia catted downpipe Cobb 3 port Stock injectors a new short block Gone through heads Link to comment Share on other sites More sharing options...
xt2005bonbon Posted July 30, 2021 Share Posted July 30, 2021 subscribed. I have a VF52 with stock injectors and basic stage 2 type stuff. Still a bit laggy to me. I tried to play with the wastegate duty cycle (i.e. close the wastegate as early as possible so as to build spool as quickly as possible). Result is kinna meh. But it is also 100F everyday right now and I live at 2600Ft. So this does not help at all either. Link to comment Share on other sites More sharing options...
blackobxt Posted July 30, 2021 Author Share Posted July 30, 2021 I thought ambient temp was going to be a game changer as it was well over 100F when I left az. Got into town this morning with temps in the low 70’s and the car was still a boring dog Link to comment Share on other sites More sharing options...
xt2005bonbon Posted July 30, 2021 Share Posted July 30, 2021 Interesting. I do see a difference when it is cooler for sure. I do hit higher loads in this case (e.g. can go from 2.5 g/rev peak to close to 3.1 g/rev or so). Link to comment Share on other sites More sharing options...
boxkita Posted July 31, 2021 Share Posted July 31, 2021 bigger turbo moves rev peak higher. Get used to driving in lower gears to keep it on boost Build my car Boxkita Track days Link to comment Share on other sites More sharing options...
blackobxt Posted July 31, 2021 Author Share Posted July 31, 2021 I’ve driven and owned plenty of big turbo cars and the payoff for delay is easily made up for with power. This setup doesn’t have that. 300ish whp isn’t exactly something to write home about and it’s almost embarrassing when you have to wait for it like that big snap is just around the corner but it never comes. Like performance anxiety lol. I’ve checked for exhaust leaks and all that, but I’m almost willing to bet there is something wrong with the turbo like a wastegate crack or something. Link to comment Share on other sites More sharing options...
seanyb505 Posted July 31, 2021 Share Posted July 31, 2021 Outback weighs a lot more, and I imagine has taller gearing than the sti. It will feel slower with an identical engine and tune to the sti. Do you have a way of seeing the boost you're hitting? I wouldn't think the 16g is miles bigger than the vf52 in terms of spool time. If everything is mechanically working as intended, my next step would be fueling. Maybe an intercooler? Link to comment Share on other sites More sharing options...
boxkita Posted July 31, 2021 Share Posted July 31, 2021 curious why you stayed with stock injectors? Perhaps running out of fuel? do you have a dyno chart? Your parts list isn't much off mine, except i have bigger injectors. Also sti is geared differently than outback, so it'll feel much more on boost. what's your intercooler? Build my car Boxkita Track days Link to comment Share on other sites More sharing options...
blackobxt Posted July 31, 2021 Author Share Posted July 31, 2021 Oh it’s going to be slower especially with the bigger tires, but even with 500lbs of luggage and passengers it’s a no contest. It’s the lag that really bugs me, the vf39 lights up quick and I know there are people making 300whp with them. I know for a fact my outback isn’t making close to 300 and it light up like a turtle Link to comment Share on other sites More sharing options...
boxkita Posted July 31, 2021 Share Posted July 31, 2021 i make 310. it doesn't really wake up until 4000. Off-boost it's a bit of a dog. Are you sure you are chasing the right goal? If you wanted streetable power, I'd have gone with a smaller turbo. Jmp makes something that is full boost at 2400rpm... Build my car Boxkita Track days Link to comment Share on other sites More sharing options...
blackobxt Posted July 31, 2021 Author Share Posted July 31, 2021 i make 310. it doesn't really wake up until 4000. Off-boost it's a bit of a dog. Are you sure you are chasing the right goal? If you wanted streetable power, I'd have gone with a smaller turbo. Jmp makes something that is full boost at 2400rpm... That might be the ticket and I might end up throwing the 16g on the shelf while I try something different. This is what the tuner sent me- “I am still very worried about the boost response as its very lazy. It doesnt spool to full boost until mid 4000's which is really late for a 16g.” I’ll upload a datalog to see what you guys think Link to comment Share on other sites More sharing options...
rhino6303 Posted July 31, 2021 Share Posted July 31, 2021 What is your wastegate duty looking like? If it's taking a lot of wastegate you may have a damaged/tilted wastegate flapper that's always slightly open. What BPV are you using? If it's leaking you might also be struggling to make boost. Link to comment Share on other sites More sharing options...
blackobxt Posted August 1, 2021 Author Share Posted August 1, 2021 These are my two most recent logs. One in 2nd followed by a 3rd I’m on the stock bpv and a rev9 eBay intercooler. I supposed the bpv could possibly be leaking. I’ll make a block off plate and see what happens.Rom raider log.csvRom raider log 2.csv Link to comment Share on other sites More sharing options...
boxkita Posted August 1, 2021 Share Posted August 1, 2021 or do a smoke test? Build my car Boxkita Track days Link to comment Share on other sites More sharing options...
blackobxt Posted August 2, 2021 Author Share Posted August 2, 2021 i did have the intake smoke tested just prior to tuning but i doubt they did anything beyond pulling the airbox and plugging the intake and filling it with smoke. i have my own little ghetto smoke machine i built but its pretty much useless unless you have a huge air leak. so itd probably be easier to just cut out a plate of sheet metal and cut a gasket and sandwich it between the bpv and intercooler Link to comment Share on other sites More sharing options...
boxkita Posted August 2, 2021 Share Posted August 2, 2021 68% wastegate duty at 2400rpm ? And stays there until mid 6000? Unless I'm reading it wrong? Build my car Boxkita Track days Link to comment Share on other sites More sharing options...
awfulwaffle Posted August 2, 2021 Share Posted August 2, 2021 I'll dig out some old logs when I get home. My previous setup was very similar to yours, aside from having bigger injectors. The 'grunt' was so violent that 1st gear was useless. Boost came up pretty early (3300ish RPM), with peak torque by 4000 RPM iirc. Note that peak boost does not equal peak torque, as some folks assume. E85 helped spool a bit too. Link to comment Share on other sites More sharing options...
NORULZleggy Posted August 2, 2021 Share Posted August 2, 2021 (edited) So my tune is in the final process and as I’ve stated in a previous post, it really feels like it leaves a lot to be desired but I’ve also thought it was in my head. I just got back from visiting wyoming and my friend who owns my old 05 sti let me borrow it for the week and I immediately knew I wasn’t wrong about outback feeling like a dog. The sti is a pretty basic stage 2 setup, and all around feels smoother and snappier and waaaay more powerful even with the stock turbo. I started to worry when my tuner was expressing concerns about by spool times not peaking till 4k. Is the 16g the issue? Should I have gone with the vf52? My setup is: Bnr16g Invidia catless up pipe Invidia catted downpipe Cobb 3 port Stock injectors a new short block Gone through heads So I have an 06 LGT. I had an 04 STI and I am not sure why you are even thinking about comparing it to an OBXT. The list is a good start but if you really want it o move out you have to put on some more parts. Parts that really count. Who is tuning your car? BTW I make 315/324 (yes I have many parts) I am limited because my trans. My 5MT has 139K miles so I do not want to push it hard. OG tranny also. It was old lady driven. If I had a Spec B or STI trans I could do more power. Also get rid of that Dual Mass fly wheels. I went with light weight fly, and wrx stage 2 clutch. My car puts down many STI/WRX and other tuned cars. Edited August 2, 2021 by NORULZleggy Link to comment Share on other sites More sharing options...
blackobxt Posted August 2, 2021 Author Share Posted August 2, 2021 I’m not really trying to compare the two cars because they will never be the same. I just want the snap that it feels like it’s missing. It does have a single mass flywheel. I have a bunch more ideas I’d like to get for the car but I’d like to dial in some of the power first Link to comment Share on other sites More sharing options...
rhino6303 Posted August 2, 2021 Share Posted August 2, 2021 Looking at the logs, you're only at 2ish psi of boost at 2500 rpm with 68% wastegate. That seems off. Can you have your tuner zero the wsategate and do a log? It would be interesting to see the boost curve on wastegate pressure only. This could further tell yoinif your wastegate flap is off. Link to comment Share on other sites More sharing options...
blackobxt Posted August 3, 2021 Author Share Posted August 3, 2021 so a little bit of an update, i work weekends so i wasnt able to work on it till today but i was able to spend plenty of time obsessing about it. I couldnt shake the feeling that i still had an exhaust leak somewhere so i used some sea foam to try and get the leak to produce some steam and sure enough i had another leak that both me and the shop missed. on the flange between the oem manifold and the invidia up pipe with a 10k old gasket. Im going to go pick up some new gaskets and pull it apart and verify that all my surfaces are flat and maybe even add a little high temp sealer. its small and i doubt its going to solve everything but its definitely an embarrassing step in the right direction. Link to comment Share on other sites More sharing options...
awfulwaffle Posted August 3, 2021 Share Posted August 3, 2021 Copper spray is your friend. I've had my car apart probably 10 times by now, and am still re-using all the (MLS) exhaust gaskets I put on when I did the first motor. Nary a leak. Link to comment Share on other sites More sharing options...
blackobxt Posted August 3, 2021 Author Share Posted August 3, 2021 The stock mls gaskets are great! Which is what leads me to believe one of the flanges might be warped. I remember thinking about checking the invidia surfaces when I unboxed it but just putting it back in its box to wait for its install then never checking it Link to comment Share on other sites More sharing options...
awfulwaffle Posted August 4, 2021 Share Posted August 4, 2021 (edited) Sorry for the delay, here's my pump logs. Relevant specs were: OEM Type RA short block, OEM B25 heads and valvetrain BNR EVO III 16G Grimmspeed 3-port EBCS Rev9-ish TMIC (unknown ebay brand bought used, resembles Perrin) Stock BPV Stock exhaust manifold Cobb catted DP Invidia UP ID1050X 4.11 gearing ambient pressure 14.24 psia Definitely seems to me like you have a leak somewhere, less boost on more wastegate at a later peak RPM. Aside from the injectors and gearing you're not set up too far off from where my car was.93_2nd.csv93_3rd.csv Edited August 4, 2021 by awfulwaffle Link to comment Share on other sites More sharing options...
blackobxt Posted August 4, 2021 Author Share Posted August 4, 2021 Sorry for the delay, here's my pump logs. Relevant specs were: OEM Type RA short block, OEM B25 heads and valvetrain BNR EVO III 16G Grimmspeed 3-port EBCS Rev9-ish TMIC (unknown ebay brand bought used, resembles Perrin) Stock BPV Stock exhaust manifold Cobb catted DP Invidia UP ID1050X 4.11 gearing ambient pressure 14.24 psia Definitely seems to me like you have a leak somewhere, less boost on more wastegate at a later peak RPM. Aside from the injectors and gearing you're not set up too far off from where my car was. Yeah your boost comes in sharper and you hit full 5-700rpm sooner, thatd be that missing snap. Link to comment Share on other sites More sharing options...
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