stepping down with exhaust sizing
Joined: Sep 2006
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From: Irvine
Originally Posted by 2big4aS2000,Jun 22 2008, 09:34 AM
254?? we have dyno many NA s2000 in the 210-220 range - this is FI - should it not be adding 85-100 hp for a turbo setup -
220ish has always been on the high side of stock s2k dynos. S2k's have dynoed as low as 180-190 stock as well.
254 on a low reading dyno isn't bad for this kit especially since the OP was running a very small sized exhaust. Other's have dynoed their greddy ap1s at 270-280 out of the box.
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From: LI, NY
254 was made on a dyno dynamics. i have no idea how they read compared to other dynos.
the 254 was at stock boost (7psi and then dropping off to 6ish) with stock cat and Hiper exhaust (which i'm now thinking is WORSE than the stock exhaust!)
and stock plugs as well. i am expecting much better numbers today at the dyno. we shall see!
the 254 was at stock boost (7psi and then dropping off to 6ish) with stock cat and Hiper exhaust (which i'm now thinking is WORSE than the stock exhaust!)
and stock plugs as well. i am expecting much better numbers today at the dyno. we shall see!
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From: LI, NY
oh man what a long horrible day.
woke up drove out to the dyno in the rain only to find the car knocking at anything over vtec point. for 3 hours we were trying to figure out what was going on, finally reverted back to stock spark plugs gapped to 35 and loaded up the original greddy basemap.
once the knock went away we started tuning away. 3 hours of actual tuning netted me a whopping 7hp peak. now i'm at 261.8. thrilling.
the only optimism is the ~20whp/ftlbs throughout the lower half of the powerband that we brought out of the car. the biggest issue is, as always, boost.
the car will hold upwards of 9psi until vtec and then i get the glorious dip of doom and boost goes down and down and down. at redline i think the gauge read 6.xx psi. if i could get the car to hold peak boost longer i'm sure i'd see a higher peak power number but it just does not seem to want to hold!!! i've been through 2 catbacks and i've added a HFC, to no avail. is the only real option to port the wastegate, or i should i continue to play with the tru boost settings?
i'm tempted to sell it all and go inline pro and make some real power.
what should i do?
woke up drove out to the dyno in the rain only to find the car knocking at anything over vtec point. for 3 hours we were trying to figure out what was going on, finally reverted back to stock spark plugs gapped to 35 and loaded up the original greddy basemap.
once the knock went away we started tuning away. 3 hours of actual tuning netted me a whopping 7hp peak. now i'm at 261.8. thrilling.
the only optimism is the ~20whp/ftlbs throughout the lower half of the powerband that we brought out of the car. the biggest issue is, as always, boost.
the car will hold upwards of 9psi until vtec and then i get the glorious dip of doom and boost goes down and down and down. at redline i think the gauge read 6.xx psi. if i could get the car to hold peak boost longer i'm sure i'd see a higher peak power number but it just does not seem to want to hold!!! i've been through 2 catbacks and i've added a HFC, to no avail. is the only real option to port the wastegate, or i should i continue to play with the tru boost settings?
i'm tempted to sell it all and go inline pro and make some real power.
what should i do?
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From: Long Island, NY
Originally Posted by TelosHedge,Jun 23 2008, 03:11 PM
oh man what a long horrible day.
woke up drove out to the dyno in the rain only to find the car knocking at anything over vtec point. for 3 hours we were trying to figure out what was going on, finally reverted back to stock spark plugs gapped to 35 and loaded up the original greddy basemap.
once the knock went away we started tuning away. 3 hours of actual tuning netted me a whopping 7hp peak. now i'm at 261.8. thrilling.
the only optimism is the ~20whp/ftlbs throughout the lower half of the powerband that we brought out of the car. the biggest issue is, as always, boost.
the car will hold upwards of 9psi until vtec and then i get the glorious dip of doom and boost goes down and down and down. at redline i think the gauge read 6.xx psi. if i could get the car to hold peak boost longer i'm sure i'd see a higher peak power number but it just does not seem to want to hold!!! i've been through 2 catbacks and i've added a HFC, to no avail. is the only real option to port the wastegate, or i should i continue to play with the tru boost settings?
i'm tempted to sell it all and go inline pro and make some real power.
what should i do?
woke up drove out to the dyno in the rain only to find the car knocking at anything over vtec point. for 3 hours we were trying to figure out what was going on, finally reverted back to stock spark plugs gapped to 35 and loaded up the original greddy basemap.
once the knock went away we started tuning away. 3 hours of actual tuning netted me a whopping 7hp peak. now i'm at 261.8. thrilling.
the only optimism is the ~20whp/ftlbs throughout the lower half of the powerband that we brought out of the car. the biggest issue is, as always, boost.
the car will hold upwards of 9psi until vtec and then i get the glorious dip of doom and boost goes down and down and down. at redline i think the gauge read 6.xx psi. if i could get the car to hold peak boost longer i'm sure i'd see a higher peak power number but it just does not seem to want to hold!!! i've been through 2 catbacks and i've added a HFC, to no avail. is the only real option to port the wastegate, or i should i continue to play with the tru boost settings?
i'm tempted to sell it all and go inline pro and make some real power.
what should i do?
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From: LI, NY
my current setup is a random tech 70mm HFC into an invidia V1 exhaust (63mm). i realize this is setup is a bottleneck but i still expected it to flow better than a stock cat to an hks hipower.
the extra power we made was a result of upping the boost 2 psi - but 7whp max gain over 2psi and a better flowing exhaust is just awful!
i was considering possibly porting the wastegate and putting on a larger flapper but i dont know, i am seeing mixed opinions about that. i could also go external if i'm up to the challenge.
its just so aggrivating. i have seen people make such better numbers on their baseline than what i have made tuned! i would love to go inline pro but i'm so deep into this kit that i dont want to lose any money on it at this point.
the extra power we made was a result of upping the boost 2 psi - but 7whp max gain over 2psi and a better flowing exhaust is just awful!
i was considering possibly porting the wastegate and putting on a larger flapper but i dont know, i am seeing mixed opinions about that. i could also go external if i'm up to the challenge.
its just so aggrivating. i have seen people make such better numbers on their baseline than what i have made tuned! i would love to go inline pro but i'm so deep into this kit that i dont want to lose any money on it at this point.
Joined: Oct 2003
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From: San Diego
What settings are you using on the truboost? I'm using a 5.5 spring rate with the gain set at 35. I hit 9.5-10 psi peak. I'm running the stock cat with a 3" single. Do you have the boost controller hookedup right?
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From: LI, NY
the boost controller works for sure, because after playing with it on the dyno we had the car making 9psi before vtec. its after vtec that the problems arise.
i have the spring pressure set at 5, and the duty cycle at 42%.
every ounce of turbo knowledge in my head reminds me that a 63mm catback is a major problem for holding boost, especially with an internally gated setup at 9,000 rpms. i keep hearing about how these turbos love to creep with too large of an exhaust though, so i'm not interested in that. i am achieving torque numbers that are acceptable (210ft lbs before vtec at 9psi), its just after vtec that is awful. the car dips noticable (~15whp) and the torque curve (and boost) plummets. power continues to rise but never makes it higher than 260. i can upload the chart but that pretty much sums it up. AFR's are tuned to a constant 11.5.
aqua, you mentioned you peak at 9.5-10psi - where in the powerband? and what is your lowest boost you see and where?
i have the spring pressure set at 5, and the duty cycle at 42%.
every ounce of turbo knowledge in my head reminds me that a 63mm catback is a major problem for holding boost, especially with an internally gated setup at 9,000 rpms. i keep hearing about how these turbos love to creep with too large of an exhaust though, so i'm not interested in that. i am achieving torque numbers that are acceptable (210ft lbs before vtec at 9psi), its just after vtec that is awful. the car dips noticable (~15whp) and the torque curve (and boost) plummets. power continues to rise but never makes it higher than 260. i can upload the chart but that pretty much sums it up. AFR's are tuned to a constant 11.5.
aqua, you mentioned you peak at 9.5-10psi - where in the powerband? and what is your lowest boost you see and where?
