Re: Banks housing and compressor wheel?
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The larger A/R won't help with the "whooosh" sound I get during upshifts? I thought my little housing was part of the cause?
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The Banks exhaust housing alone did not directly address compressor surge/stall issues. If anything, the combination of the larger exhaust housing and the Banks original Ottomind chip programming made the chirping of the turbo more evident, when under load... experienced often in my case at shift points while powering up hills.
Banks Engineering addressed this issue by subsequently including a new compressor wheel with their PowerPack systems, beginning in 2001. In my case, it was only after Banks put in the new compressor wheel did the surge (chirping/whooshing) go away. Prior to that, with only the Banks 1.0 A/R ratio exhaust housing, I had to monitor the throttle when I heard those sounds coming on.
The new Banks compressor wheel, which is said to be the same as the Ford factory 99 turbo wheel made prior to the 99.5 update, and is likely very near the same alternating blade cut as Riley's branded "Wicked Wheel", seemed to me to reduce boost response in my truck. I lived with this, as it seemed better than the known consequences of inducing surge/stall.
To be fair to Gale Banks, Gale personally assured me that his testing did not bear out any significant loss in boost performance... i.e. the type of loss that I seem to have noticed. In fact, his firm belief is that on balance, MORE POWER can be obtained with the new compressor wheel, because the surge curve is moved as a result. We tested my truck on his dyno, but could not adequately test the truck with the original compressor wheel because the truck would hit the surge/stall wall at a certain point, and naturally his dyno technician didn't want to destroy the turbo.
Having physically compared both wheels in hand and on the truck, I've noticed that the modified wheel allows more pressure relief, with every other blade curled short of extending all the way to the clearance distance tolerance of the housing, and as such, may be a little less efficient at compressing the air in the stock compressor housing. But that relief is welcome, when compared to the stress of driving uphill in fear of destroying the turbo if you need to get on it to pass a slower moving semi.
The newer ported housing from Garrett (and rebranded by ATS) might be a more elegantly designed solution, albeit more costly than just replacing the wheel. I have no information on how robust the newer compressor housings are.
As for the exhaust housing, larger doesn't necessarily mean more power. The velocity of the exhaust gasses racing through the scrolled housing are generally increased with the smaller housings. But of course, so then is the heat. Comparing 7.3L stock and Banks housings to larger displacement 6 cylinder diesels, such as the 466, the 530, the C8.3, the M11, etc, makes the latter seem downright tiny compared to the former.
The best solution (in my opinion) is a total engineered solution, tested, verified, and mapped (with a compressor map) to a specification for the displacement volume and boost expected. I'm not sure how the home hybridized solutions that are piece-mealed together from different aftermarket vendors have worked in the long run... because the motors of the people who try them end up getting windowed out of commission for some other reason.
Good luck getting your surging sorted. The wheel, not the exhaust housing, sorted mine. But had the exhaust housing not been changed, and had the programming not been changed, the surge would not likely have come on as soon as it had. Fortunately, Gale Banks addressed the issue in my case, as well as in all other cases subsequent to 2000 with the improved post-2000 PowerPack, with his fairly comprehensively tested housing/wheel combination.
However, it is quite likely that the original International compressor map was not flawed for the power levels originally intended, making a change in wheel unnecessary for a bone stock, non-reprogramed application.
2000 F-550 CC 4x4 7.3L 4R100 MSOF CNH4; Racor CCV3550-FRD-02, AIS, AIC, and NO deletes.
Banks Intercooler & Pipes, 3.5 down & out, Big Head, Quick Turbo & Wheel, and NO chips/programs.