jackal8788 Posted September 18, 2014 Author Share Posted September 18, 2014 23.5 peak, tapering to 19 at redline. I'm going to post another plot of the boost with this turbo and with my stock turbo just to visually show the lag difference. VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
jackal8788 Posted September 18, 2014 Author Share Posted September 18, 2014 This graph shows the difference in lag between the stock VF54 and the BNR 20G: VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
wrxwhit Posted September 18, 2014 Share Posted September 18, 2014 Much quicker getting to redline than my stock vf54 . How do you like it so far. Probably way different car now with bigger turbine. Now a highway car instead of a city car   Sent from my iPhone using Tapatalk Link to comment Share on other sites More sharing options...
jackal8788 Posted September 18, 2014 Author Share Posted September 18, 2014 Much quicker getting to redline than my stock vf54 . How do you like it so far. Probably way different car now with bigger turbine. Now a highway car instead of a city car   Sent from my iPhone using Tapatalk I really do like it. Your description of a highway car is perfect and that's really where it shines now. I don't have quite as hard of a punch on the low end, but the car just pulls so incredibly hard up to 6k and that was certainly where the stock VF54 ran out of breath and fell flat.  On a sidenote, this turbo sounds cool as hell when it starts spooling at hitting 7-8 PSI. Granted, I removed the intake silencer and put on a different air filter at the same time I upgraded the turbo so I can't compare directly to the sound of the VF54 but it sounds like a jet now! VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
jackal8788 Posted September 18, 2014 Author Share Posted September 18, 2014 I would really like to see an 18G boost curve posted next to the stock curve - I'm curious how well it spans the gap between stock and the 20G. VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
s2baru Posted September 18, 2014 Share Posted September 18, 2014 That's what I like to hear. I'm going for ny highway driveability and someo cassional track usage so holding power later in the powerband is what im shooting for. Hope you're enjoying the new tune!! Link to comment Share on other sites More sharing options...
jackal8788 Posted September 18, 2014 Author Share Posted September 18, 2014 (edited) Much quicker getting to redline than my stock vf54 . How do you like it so far. Probably way different car now with bigger turbine. Now a highway car instead of a city car   Sent from my iPhone using Tapatalk That's what I like to hear. I'm going for ny highway driveability and someo cassional track usage so holding power later in the powerband is what im shooting for. Hope you're enjoying the new tune!! Totally enjoying it! At least once a day I find myself grinning after a spirited pull in second or third. Edited September 18, 2014 by jackal8788 VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
fahr_side Posted September 19, 2014 Share Posted September 19, 2014 I would really like to see an 18G boost curve posted next to the stock curve - I'm curious how well it spans the gap between stock and the 20G.  I've tuned both. The 18G spools a tiny bit faster but flows as much air. This motor is so limited by the exhaust cams that the extra compressor flow is useless. Obligatory '[URL="http://legacygt.com/forums/showthread.php/2008-gh8-238668.html?t=238668"]build thread[/URL]' Increased capacity to 2.7 liters, still turbo, but no longer need spark plugs. Link to comment Share on other sites More sharing options...
acumenhokie Posted September 19, 2014 Share Posted September 19, 2014 I've tuned both. The 18G spools a tiny bit faster but flows as much air. This motor is so limited by the exhaust cams that the extra compressor flow is useless. Can't you use the AVCS to help mitigate some of that? Link to comment Share on other sites More sharing options...
fahr_side Posted September 19, 2014 Share Posted September 19, 2014 Can't you use the AVCS to help mitigate some of that? You can certainly use AVCS tweaks to improve spool or low rpm torque. The top-end airflow though... you use the same techniques on either turbo it all comes out the same. You can't make up for the loss in duration and 1mm less lift compared to the old single AVCS or STi D-AVCS unit. The only solution I see for this is using the STi exhaust cams or going aftermarket. Obligatory '[URL="http://legacygt.com/forums/showthread.php/2008-gh8-238668.html?t=238668"]build thread[/URL]' Increased capacity to 2.7 liters, still turbo, but no longer need spark plugs. Link to comment Share on other sites More sharing options...
acumenhokie Posted September 19, 2014 Share Posted September 19, 2014 You can certainly use AVCS tweaks to improve spool or low rpm torque. The top-end airflow though... you use the same techniques on either turbo it all comes out the same. You can't make up for the loss in duration and 1mm less lift compared to the old single AVCS or STi D-AVCS unit. The only solution I see for this is using the STi exhaust cams or going aftermarket. So the D-AVCS on the LGT different than the D-AVCS on the STi? Link to comment Share on other sites More sharing options...
fahr_side Posted September 19, 2014 Share Posted September 19, 2014 So the D-AVCS on the LGT different than the D-AVCS on the STi? The actuators and pulleys are the same, so the retard range is the same. The exhaust cam profile and lobe are however not the same, they're much more like the old EJ205 profiles... 1mm less lift than the usual single-AVCS EJ255 or ('04~'07) 257 cams. You can see the volumetric efficiency 'go over the falls' a lot earlier on the Legacy motor vs. the STi unit or even the single-AVCS EJ255s. The '08~ STi D-AVCS cams are assumed to fit the Legacy heads though, as the part numbers for the pulleys are the same, the heads are a really similar casting, and they even have a drive slot on the passenger side cam to run the turbo oil scavenge pump. FujiK posted photos in another thread to show that. Obligatory '[URL="http://legacygt.com/forums/showthread.php/2008-gh8-238668.html?t=238668"]build thread[/URL]' Increased capacity to 2.7 liters, still turbo, but no longer need spark plugs. Link to comment Share on other sites More sharing options...
s2baru Posted September 19, 2014 Share Posted September 19, 2014 Just to chime in on the cam situation. I put the GSC stage 1 for +08sti and the that exact problem came up. JohnJohn had to have them takne to a machine shop to compensate foe the scavenger pump like fahr_side just mentioned. Also to help with flow I went with +1 exhaust(33mm)/intake(37mm) valves fwiw. Hasnt beem tuned yet so unsure for any noticable gains but ill share results after breakin on stock turbo. Link to comment Share on other sites More sharing options...
fahr_side Posted September 19, 2014 Share Posted September 19, 2014 I would be really interested to see your results! So aside from the lack of a slot to drive the oil scavenge pump the cams went straight in eh? Good to have that confirmed. Thanks. I don't expect you'll pick too much up on the stock turbo, seeing how it falls down past about 5k6rpm. Time to go larger! I love how the short, EL header on this car deals with the larger turbos. Much faster spool and much better boost control compared to the oldskool 6' long header. It will be really interesting to see how that goes with some proper cams in place. Obligatory '[URL="http://legacygt.com/forums/showthread.php/2008-gh8-238668.html?t=238668"]build thread[/URL]' Increased capacity to 2.7 liters, still turbo, but no longer need spark plugs. Link to comment Share on other sites More sharing options...
GTEASER Posted September 19, 2014 Share Posted September 19, 2014 Subscribed to glean wisdom. GTEASER's 2012 Legacy GT - Sold GTEASER's 2009 XTeaser - Sold GTEASER's 1992 Legacy SS - Sold Link to comment Share on other sites More sharing options...
s2baru Posted September 19, 2014 Share Posted September 19, 2014 I would be really interested to see your results! So aside from the lack of a slot to drive the oil scavenge pump the cams went straight in eh? Good to have that confirmed. Thanks. I don't expect you'll pick too much up on the stock turbo, seeing how it falls down past about 5k6rpm. Time to go larger! I love how the short, EL header on this car deals with the larger turbos. Much faster spool and much better boost control compared to the oldskool 6' long header. It will be really interesting to see how that goes with some proper cams in place. Exactly. Downside of our turbo is the housing is 7.5. Its been said before, great for lowend but not much up top. I've still yet to decide on what turbo to go with with all these new options becoming available. Custom header etc still seems to be my plan. All up in the air for now. Link to comment Share on other sites More sharing options...
ebo03 Posted September 20, 2014 Share Posted September 20, 2014 Exactly. Downside of our turbo is the housing is 7.5. Its been said before, great for lowend but not much up top. I've still yet to decide on what turbo to go with with all these new options becoming available. Custom header etc still seems to be my plan. All up in the air for now. What other new options aside from Steamspeed? And did we ever hear how islandborn's tune with the Steamspeed turbo went? Link to comment Share on other sites More sharing options...
jackal8788 Posted September 20, 2014 Author Share Posted September 20, 2014 We did not! There was speculation that the turbo may actually have caused him to create a rip in the time space continuum.... VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
jackal8788 Posted September 20, 2014 Author Share Posted September 20, 2014 As for other options, Tomioka is the only other bolt up that I am aware of. Haven't seen much about them on this forum. They are similar in price to BNR but I'm not sure how well they stand behind their work as compared to Brian. VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
fahr_side Posted September 20, 2014 Share Posted September 20, 2014 (edited) Yes, the exhaust housing is a problem. I'm not a huge fan of the TD05H-20G combination on the 2.5 liter engines. You always need to balance intake and exhaust flow, and this combo is a bit choked on the hot side. In the old location I'd only use this pair of wheels in an 8cm2 exhaust housing. Now add the weak exhaust cams on the 5th gen and the only available P18 (7.5cm2) housing.. the imbalance is even worse. The P18's geometry is great for the TD05H turbine (I use this on my own car) but a TD06SL2 is just too large... horribly low A/R from this. I have seen a couple of cars with handmade EWG headers do a little better up top, but one with a GT3037R grafted on really didn't do much more than the other car with a 20G. Again I'm sure this is due to the cams. Disclaimer: I didn't tune these two and only saw plots and not logs. I think there will be complete (not hybrid) stock-location upgrade turbos for the new WRX coming to market within a year but it's expensive to tool-up for a housing. If those guys run into a wall with fueling the market will be too small to support that. Which one to buy right now? After testing many Kamak turbos there are two things I'd mention about these units. They now use parts made almost exclusively in China and IME the quality has taken a big dip in recent years. I've seen a lot of failures at very low miles. I've seen a few of billet wheels come apart very soon after install. The equal-height blade billet compressors they produce had the lowest efficiency of any we had tested. At any boost level we had to run less timing than with any other equivalent 20G wheel, cast or billet, and the flow on them was no better than a genuine MHI 18G cast wheel. The 5-high / 5-low design from them I tested in 16G size also did nothing the regular cast version didn't. Given the current options and my experience with Bryan and his turbos, I'd go with the BNR. If you are sticking with stock cams, definitely get the 18G. The E85 guys might ask Bryan if the 71HTA is still available. Motors running corn are a lot less sensitive to exhaust flow it seems. Edited September 20, 2014 by fahr_side Obligatory '[URL="http://legacygt.com/forums/showthread.php/2008-gh8-238668.html?t=238668"]build thread[/URL]' Increased capacity to 2.7 liters, still turbo, but no longer need spark plugs. Link to comment Share on other sites More sharing options...
s2baru Posted September 20, 2014 Share Posted September 20, 2014 The more you know. Sorry to go a little sideways here with the convo Jackal. As for the Kamak name...I've never heard of them. Link to comment Share on other sites More sharing options...
fahr_side Posted September 20, 2014 Share Posted September 20, 2014 The more you know. Sorry to go a little sideways here with the convo Jackal. As for the Kamak name...I've never heard of them. Kamak are a big replacement turbo manufacturer in Taiwan, now branching out into upgrade turbo territory. They supply Steamspeed. I used to rate them very highly but they've recently decided to compete against Chinese suppliers by using more Chinese parts and leverage the Made in Taiwan label. Kamak also owns the Kinugawa brand used to move turbos that didn't quite make the cut for the Kamak label direct to market and compete head to head with the Chinese ebay turbos. Yes, anytime just blow the whistle Jackal8788. No intent to derail you. Obligatory '[URL="http://legacygt.com/forums/showthread.php/2008-gh8-238668.html?t=238668"]build thread[/URL]' Increased capacity to 2.7 liters, still turbo, but no longer need spark plugs. Link to comment Share on other sites More sharing options...
jojorios Posted September 20, 2014 Share Posted September 20, 2014 We did not! There was speculation that the turbo may actually have caused him to create a rip in the time space continuum.... LMFAO!! Can't stop laughing. Sorry this just made my night. Link to comment Share on other sites More sharing options...
acumenhokie Posted September 20, 2014 Share Posted September 20, 2014 Yes, the exhaust housing is a problem. I'm not a huge fan of the TD05H-20G combination on the 2.5 liter engines. You always need to balance intake and exhaust flow, and this combo is a bit choked on the hot side. This is very true and something I was aware of when I was reading through some of the stickies over at NASIOC. One of the reasons I was so keen to go to an EWG is that it mentions that an EWG is even more effective in scenarios where you have a smaller turbine (TD05) with a bigger compressor (20G). Link to comment Share on other sites More sharing options...
jackal8788 Posted September 20, 2014 Author Share Posted September 20, 2014 (edited) Guys, keep it coming! I'm enjoying the free education here so no worries about sidetracking. Please keep the wisdom flowing! Edited September 22, 2014 by jackal8788 VF54 to 20G to VF54 to 18G build thread Link to comment Share on other sites More sharing options...
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