Should I go 7163 instead of 7670
02-19-2017, 05:13 PM
#11
11 afr sounds conservative 
I was trying to adjust it anywhere from that to 13.5 and spool is definitely fastest at 13.5 (I'm not keeping that...)
I'm using standard BW canister.
Tried plugging to intake mani/turbo outlet/through boost controller - doesn't make any significant difference in spool time, only max boost. I even tried to block it completely (watched closely on boost to disengage throttle once boost hit 15) - same result: it spools to 12-15 at 5k on 3rd, 4.5k on 4th and 3.8k at 6th.
My header is small volume, tubular type but not equal length.
I was trying to adjust it anywhere from that to 13.5 and spool is definitely fastest at 13.5 (I'm not keeping that...)I'm using standard BW canister.
Tried plugging to intake mani/turbo outlet/through boost controller - doesn't make any significant difference in spool time, only max boost. I even tried to block it completely (watched closely on boost to disengage throttle once boost hit 15) - same result: it spools to 12-15 at 5k on 3rd, 4.5k on 4th and 3.8k at 6th.
My header is small volume, tubular type but not equal length.
I had read on an EVO forum that one of the guys noticed a fairly large pressure difference from Compressor housing to manifold pressure, If I recall the pressure at the compressor housing was 3-4 PSI higher than the manifold pressure and would open the WG prematurely (typically, there is a ~1 PSI differential between the two). I didn't experiment with this myself, but it made sense as my WG was definitely opening prematurely. I have my TurboSmart actuator tightened a few extra threads to help hold the WG shut while building boost (TurboSmart uses a linear spring for Pressure rather than a progressive spring like the BW unit). Though if you tried controlling at the manifold, this would have eliminated this issue for you.
I also upgraded the BPV to the TurboSmart one, but I doubt that has any affect on spool time, it's still a recirculation style valve, it is just more robust.
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Alexander Startsev (02-19-2017)
02-19-2017, 05:23 PM
#13
Yes, I am tuned pretty conservative. Are you street tuning it or Dyno tuning it? One thing I found was that the BW actuator was almost never closed, even when I wasn't making desired boost pressure, the WG would be 1/4-1/2 open, I was able to see that while the car was on the Dyno. I saw your other thread about poor boost control as well, and similarly, the BW Actuator did that to me as well, no matter what I did for boost control. I could visually watch it swing open and slam shut multiple times on a pull trying to control boost. Once I switched to the TurboSmart actuator, both of those issues went away. I did not take notice of a change in spool time, but pressure is much more stable and the Kpro Boost Control is working well. I am sure this helped spool time though as the WG is now holding shut while building boost.
I had read on an EVO forum that one of the guys noticed a fairly large pressure difference from Compressor housing to manifold pressure, If I recall the pressure at the compressor housing was 3-4 PSI higher than the manifold pressure and would open the WG prematurely (typically, there is a ~1 PSI differential between the two). I didn't experiment with this myself, but it made sense as my WG was definitely opening prematurely. I have my TurboSmart actuator tightened a few extra threads to help hold the WG shut while building boost (TurboSmart uses a linear spring for Pressure rather than a progressive spring like the BW unit). Though if you tried controlling at the manifold, this would have eliminated this issue for you.
I also upgraded the BPV to the TurboSmart one, but I doubt that has any affect on spool time, it's still a recirculation style valve, it is just more robust.
I had read on an EVO forum that one of the guys noticed a fairly large pressure difference from Compressor housing to manifold pressure, If I recall the pressure at the compressor housing was 3-4 PSI higher than the manifold pressure and would open the WG prematurely (typically, there is a ~1 PSI differential between the two). I didn't experiment with this myself, but it made sense as my WG was definitely opening prematurely. I have my TurboSmart actuator tightened a few extra threads to help hold the WG shut while building boost (TurboSmart uses a linear spring for Pressure rather than a progressive spring like the BW unit). Though if you tried controlling at the manifold, this would have eliminated this issue for you.
I also upgraded the BPV to the TurboSmart one, but I doubt that has any affect on spool time, it's still a recirculation style valve, it is just more robust.
I street tune so never saw wg it in action. Wonder if i should remove the hood, mount go-pro and record
I'll probably start from try to tightening it as much as it will let me and see if it makes difference in spool time ...
02-20-2017, 08:12 AM
#14
Make sure the actuator is completely shut, then pull the vacuum line and go for a ride. This has obvious concerns but just regulate boost with your right foot and let off as needed.
04-14-2018, 09:20 PM
#15
How fast do you want the turbo to build boost? my 7670 is at 15+ PSI at 4,000 without any sort of anti-lag type of tuning. I had to keep my VTEC engagement high (4800) to avoid low end boost spikes, we were originally getting 20+ PSI spikes as early as ~3000 when we had VTEC engagement that low. If I am rolling in 4th or 5th at 4,000+ and nail it, it's literally almost instantaneous, I've surprised a few local kraftwerks guys. I have a very long & wide runner custom manifold as well, so I would expect mine to be "laggier" than most EFR setups.
Also, where are you for power currently? I've been contemplating upgrading to the 8374 due to the 7670 running out of breath above 8,000. I'm sitting right at ~500WHP, but I don't think I'd be able to squeeze any more out of it without going e85 or getting a 8374Wi. I start to get pretty severe boost droop right around 7,500. I couldn't imagine stepping down to a 7163.
Also, where are you for power currently? I've been contemplating upgrading to the 8374 due to the 7670 running out of breath above 8,000. I'm sitting right at ~500WHP, but I don't think I'd be able to squeeze any more out of it without going e85 or getting a 8374Wi. I start to get pretty severe boost droop right around 7,500. I couldn't imagine stepping down to a 7163.
04-22-2018, 09:07 PM
#16
I haven't measured MAF (MAP car) but I am around 2.2-2.3 ratio, about 51-52 lb/min to get ~500WHP (Dyno'ed 480s back to back multiple times at 14 PSI). Turbo is running along the choke line and I can tell once I am above 7500 RPMs. Power stays flat but boost droops steadily down to ~12 with a WG that isn't opening.
04-23-2018, 12:25 AM
#17
I haven't measured MAF (MAP car) but I am around 2.2-2.3 ratio, about 51-52 lb/min to get ~500WHP (Dyno'ed 480s back to back multiple times at 14 PSI). Turbo is running along the choke line and I can tell once I am above 7500 RPMs. Power stays flat but boost droops steadily down to ~12 with a WG that isn't opening.
04-23-2018, 11:16 AM
#18
Lol, I know. Space restraints. I am not sure if a 8374 would fit, my turbine housing is about 5mm from the vtec solenoid. I’ve been looking for someone locally that has a 8374 that would let me test fit. Most people don’t run EFRs though.
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