Wastegates not effective?
Might put a gauge on your exhaust and measure the backpressure, good info to have either way. Peak and hold tire pressure gauge is cheap and easy. Low backpressure setups are really picky about gate positioning. I’ve seen setups so picky that just the install/removal of the turn down on the gate made a huge difference.
*update*
I had to take the compressor housings apart, but I took them off and tapped them for 1/8npt..
I then put equal length silicone hose to the wastegates and tried it with the super light springs ... I haven't done a thorough all rpm test because I was on limited time , but it pulled up to 3lbs of boost instead of 12+ .. It also stayed there pretty rock solid - so now I've got some tuning to do !!!
Thanks for the input on my problem!!!
I had to take the compressor housings apart, but I took them off and tapped them for 1/8npt..
I then put equal length silicone hose to the wastegates and tried it with the super light springs ... I haven't done a thorough all rpm test because I was on limited time , but it pulled up to 3lbs of boost instead of 12+ .. It also stayed there pretty rock solid - so now I've got some tuning to do !!!
Thanks for the input on my problem!!!
the IC is one of those godspeed cheapie units until i can afford to replace it with something better.
i really think that if i were to measure the output of my homemade boost tee thing (thats located under the main 3" inlet to the tb) that there is not as much boost signal as there is in the actual intake manifold...
i actually have been thinking that the inlet pipe itself could be too small anyway but at any rate a lot of velocity through that pipe and i dont think it would be hard for a "venturi effect" to negate the pressure i should be seeing out of said port. being in the actual intake would have probably had a similar effect to tapping into the compressor housings but the hoses would have been longer , and in the turbo housing you are right i will get a little more pressure (i wont lose pressure through the intercooler like you indicate) and i will have that extra oomph to get the wastegates off of their seat just a little earlier
to be honest i also just did it to give them their best chance of even working at all - turns out it worked and i think uncovered a weak spot in the boost tee engineering
i really think that if i were to measure the output of my homemade boost tee thing (thats located under the main 3" inlet to the tb) that there is not as much boost signal as there is in the actual intake manifold...
i actually have been thinking that the inlet pipe itself could be too small anyway but at any rate a lot of velocity through that pipe and i dont think it would be hard for a "venturi effect" to negate the pressure i should be seeing out of said port. being in the actual intake would have probably had a similar effect to tapping into the compressor housings but the hoses would have been longer , and in the turbo housing you are right i will get a little more pressure (i wont lose pressure through the intercooler like you indicate) and i will have that extra oomph to get the wastegates off of their seat just a little earlier
to be honest i also just did it to give them their best chance of even working at all - turns out it worked and i think uncovered a weak spot in the boost tee engineering
10 Second Club
Joined: Jul 2011
Posts: 176
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From: Seattle
OP where are you measuring boost from? My point being that if you are measuring it at the intake it doesn't matter what you pressure drop is, those gates should have opened long before 12 psi. The only thing that really makes sense is that the reference lines to the gates were not being pressurized for some reason. One way to test would be to disconnect the lines all together and see if they open sooner than they did before if they do then there was likely vacuum being pulled on the reference lines.
All of that said I am sure it doesn't matter anymore but inquiring minds...
9 Second Club
Joined: Nov 2003
Posts: 13,616
Likes: 185
From: Norn Iron
I am not completely sure I buy that this is a pressure drop issue but maybe.
OP where are you measuring boost from? My point being that if you are measuring it at the intake it doesn't matter what you pressure drop is, those gates should have opened long before 12 psi. The only thing that really makes sense is that the reference lines to the gates were not being pressurized for some reason. One way to test would be to disconnect the lines all together and see if they open sooner than they did before if they do then there was likely vacuum being pulled on the reference lines.
All of that said I am sure it doesn't matter anymore but inquiring minds...
OP where are you measuring boost from? My point being that if you are measuring it at the intake it doesn't matter what you pressure drop is, those gates should have opened long before 12 psi. The only thing that really makes sense is that the reference lines to the gates were not being pressurized for some reason. One way to test would be to disconnect the lines all together and see if they open sooner than they did before if they do then there was likely vacuum being pulled on the reference lines.
All of that said I am sure it doesn't matter anymore but inquiring minds...
If you have a 10psi restriction across the IC then everything is working of false pressures including the gates.
The only way your lines would not be pressurising, is if there was a leak somewhere, which is of course possible
And there is no way ever the w/g lines would see vacuum from your boost pipe. Never...ever.
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Verdad Gallardo Just a follow up, I switched my "test springs" (a really light set of springs i got from a guy at a starter rebuild shop out of some random starter solenoids) for brand new turbonetics 5-7 lb springs (blue).
I am now getting a rock solid 5 psi. My logs of my map sensor readings are right there at 5 as well, consistently.
Im not trying to argue with anyone, i just think the attachment onto the side of a column of air in my home made "boost tee" was a bad idea. If i did have a huge pressure drop thru the IC it would manifest itself in my gates opening further than what the engine sees and it is not.
I mainly post this follow up so anyone doing a search can find this helpful. a bad boost reference location even if you think its good can be bad when switching from vacuum to boost, IMO. Also, the waste gate install must not be too bad - they are regulating precise as can be at this time (might show to change as boost comes up but i doubt it)
thanks for the help everyone im glad we got it figured out!!
I am now getting a rock solid 5 psi. My logs of my map sensor readings are right there at 5 as well, consistently.
Im not trying to argue with anyone, i just think the attachment onto the side of a column of air in my home made "boost tee" was a bad idea. If i did have a huge pressure drop thru the IC it would manifest itself in my gates opening further than what the engine sees and it is not.
I mainly post this follow up so anyone doing a search can find this helpful. a bad boost reference location even if you think its good can be bad when switching from vacuum to boost, IMO. Also, the waste gate install must not be too bad - they are regulating precise as can be at this time (might show to change as boost comes up but i doubt it)
thanks for the help everyone im glad we got it figured out!!
I don't doubt if there could have been a leak. I don't mean there was going to be a pure vacuum signal coming from the ports , just a Venturi effect in the charge pipe that offset the amount of boost coming out of the tee