Cold-side boost control
#26
Old [Sch|F]ool
Usually used to stay on the stable side of surge line on the low flow side of the compressor map while staging drag cars. Massive power loss and temperature issues running the turbo flat out, generally not possible at stall rpm either on auto cars if the turbo is big enough to bother doing it.
European Rallycross cars do this too, so they can run a giant turbo that makes 600hp and not surge at low engine speed. They redirect the airflow to the exhaust manifold and closely control turbocharger speed with a combination of this and fueling/ignition timing so the engine can spool the turbo without melting it down, since they need to be able to have good response coming off of a corner.
It is similar to bang-bang antilag but much more subtle in how it works, it isn't just in operation when off throttle. The turbo is kept spinning at its best speed and the valve is controlled to bleed off pressure as necessary to keep flow up and away from the surge line while allowing as much as possible into the engine.
Last edited by peejay; 12-31-23 at 06:34 AM.
#29
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even the wastegates have wastegates!
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mr2peak (01-20-24)
#30
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Cool guy, he's got two first gens. The other is some crazy tube-chassis contraption that he made.
#32
Rotary Enthusiast
I wanna know what he's thinking. I'd usually say I'll have what he's smoking, but that looks a bit beyond what I'm willing to put in my body.
#33
if it’s T321 pipe rather than the usual T304 variety then it’s significantly stronger at higher temperature. Technically T321 16 Ga. tubing or Sch 5 pipe is strong enough compared to the Sch. 10 thickness that’s typically used for T304 pipe.
there are sound reasons for not trying to put anti-lag air that deep into the exhaust port compared to where it is on the manifold pipe. There technically isn’t anything wrong with what he did, but the anti-lag air supply lines could have been formed thin-wall tubing with NPT/tube fitting adapters on each end rather than welded pipe.
Welded pipe for those is overkill, but he likely had his own reasons for the choice. Likely it being self-supporting if I had to guess.
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there are sound reasons for not trying to put anti-lag air that deep into the exhaust port compared to where it is on the manifold pipe. There technically isn’t anything wrong with what he did, but the anti-lag air supply lines could have been formed thin-wall tubing with NPT/tube fitting adapters on each end rather than welded pipe.
Welded pipe for those is overkill, but he likely had his own reasons for the choice. Likely it being self-supporting if I had to guess.
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Last edited by TeamRX8; 01-20-24 at 02:50 PM.
#35
I suppose you must of never had to fabricate large diameter intake tubing where a standard radius either didn’t work or were a lot harder to fit without having to throw several expensive bends away getting it just right.
I don’t think he’s intending to build a show car that just sits and looks pretty on the the convention center circuit. How about cutting the guy some slack. There are some things going on there that are rarely if ever seen on this forum. Right inline with the thread topic even.
The extra DBW TB isn’t intended as a decoration any more than the pie cuts.
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I don’t think he’s intending to build a show car that just sits and looks pretty on the the convention center circuit. How about cutting the guy some slack. There are some things going on there that are rarely if ever seen on this forum. Right inline with the thread topic even.
The extra DBW TB isn’t intended as a decoration any more than the pie cuts.
.
#37
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Don't have anything (of value) to add to this discussion regarding manifold design and the like but some of you might get a kick out of this. Spoke with the person who owns the car/fabricated the manifold this past weekend when we were scanning my interior and the main reason for the addition of a turbocharger was to reduce noise as his previous N/A setup was loud enough to require ear plugs whilst driving as mufflers alone were not sufficient to achieve the desired noise level.
#38
Rotary Enthusiast
Pulled the engine to fix a front seal leak and fit the e-gate. Space is tight! Need to chop a bit out of the mount, and cut / re-route the oil drain to fit properly. Unsure how it will clear the RHD steering rack, it's going to be tight engine might come out again to get the clearances right. We measured and eye-balled it, so fingers crossed the mount is clocked correctly the first time. Might need to put a Z bend in the rod, the angle is close enough make me a little nervous but far from locking up on the arm.
Still no answer from Full Race for the amp draw. The wires are small so it shouldn't be an issue but a real answer would be nice.
Still no answer from Full Race for the amp draw. The wires are small so it shouldn't be an issue but a real answer would be nice.
#40
Rotary Enthusiast
Arm length is no problem, I have a few of them. Spacing out the mount just makes the oil drain issue worse.
Just realized I posted this in the cold side boost thread and not the e-gate thread.
Just realized I posted this in the cold side boost thread and not the e-gate thread.
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