Am I wrong thinking my 2860 should be able to push 20+psi?
#1
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So after the car having an extended nap and getting most of it sorted I started trying top push the envelope a bit more. Plugged in 22psi as my boost target on the Hydra and I could get an initial hit of 24 but it would settle to 17. I readjusted my max duty cycle on the solenoid and didn't see a difference. The other day I was out with the car driving and flogging the hell out of it, got home and found the line to the wastegate had come off completely. Still settling to 18ish psi at 5800 revs with a spike closer to 24psi around 4000rpm.
.64 exhaust housing, 8psi internal gate. Ingersol Rand solenoid at 90% duty cycle
Time for a bigger snail?
.64 exhaust housing, 8psi internal gate. Ingersol Rand solenoid at 90% duty cycle
Time for a bigger snail?
#2
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You can get a stronger actuator and probably hold a bit more, but overall it probably won't do too much more because it's likely choking up. A bigger hotside would also help, but again only so much.
Instead of the fascination with pressure (restriction of flow) you should be talking about hp output vs hp goals vs overall car goals.
what are they?
Instead of the fascination with pressure (restriction of flow) you should be talking about hp output vs hp goals vs overall car goals.
what are they?
#7
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Is the manifold replaced already? I pushed 17psi and came up JUST shy of 300 at 296hp/270tq. I would try the dyno again, make sure your AFRs sit between 12 and 11.5:1 and your in-boost timing is advanced enough to build power. I copied Paul's map for his 2560 setup to get to my power levels. I'd try a manual boost controller as well, maybe your WG is opening too soon?
#8
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So after the car having an extended nap and getting most of it sorted I started trying top push the envelope a bit more. Plugged in 22psi as my boost target on the Hydra and I could get an initial hit of 24 but it would settle to 17. I readjusted my max duty cycle on the solenoid and didn't see a difference. The other day I was out with the car driving and flogging the hell out of it, got home and found the line to the wastegate had come off completely. Still settling to 18ish psi at 5800 revs with a spike closer to 24psi around 4000rpm.
.64 exhaust housing, 8psi internal gate. Ingersol Rand solenoid at 90% duty cycle
Time for a bigger snail?
.64 exhaust housing, 8psi internal gate. Ingersol Rand solenoid at 90% duty cycle
Time for a bigger snail?
#10
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Is the manifold replaced already? I pushed 17psi and came up JUST shy of 300 at 296hp/270tq. I would try the dyno again, make sure your AFRs sit between 12 and 11.5:1 and your in-boost timing is advanced enough to build power. I copied Paul's map for his 2560 setup to get to my power levels. I'd try a manual boost controller as well, maybe your WG is opening too soon?
#12
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The rule of thumb I always heard was that an EBC was good for holding about twice the WG spring pressure reliably. Above that it would be more likely to crack open just a little and leak off pressure slightly. If you are interested in running around 20psi or more, try a 15lb WG and see if your results improve. Or wire the WG shut and see what KPA max really is.
#18
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I had boost spike issues until I home-ported my turbine housing (channel/trench leading to WG flapper, see here). PITA but once done it's done.
Another thing folks haven't mentioned (maybe it was only me?) but if you're running say, 20 PSI and have an 8psi wastegate spring when the boost controller (either electronic or manual) opens the boost is going to overpower the spring and slam the WG door open/closed like a ragdoll. In my case on an 8psi spring with a manual controller adjusted to ~15psi I spiked to 17.9psi with fluctuations down to as low as 10psi, dropped to 14psi by redline. Putting in a 15psi spring (actually holds ~14psi at gauge/hydra) largely resolved this issue but I'm using a cheap MBC right now so it still fluctuates a bit. The best solution is a properly functioning electronic controller with a wastegate actuator no less than 1/2 of the boost level you intend to run though ideally.
Another thing folks haven't mentioned (maybe it was only me?) but if you're running say, 20 PSI and have an 8psi wastegate spring when the boost controller (either electronic or manual) opens the boost is going to overpower the spring and slam the WG door open/closed like a ragdoll. In my case on an 8psi spring with a manual controller adjusted to ~15psi I spiked to 17.9psi with fluctuations down to as low as 10psi, dropped to 14psi by redline. Putting in a 15psi spring (actually holds ~14psi at gauge/hydra) largely resolved this issue but I'm using a cheap MBC right now so it still fluctuates a bit. The best solution is a properly functioning electronic controller with a wastegate actuator no less than 1/2 of the boost level you intend to run though ideally.