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I have an old log-style Toyomoto manifold. The turbo and manifold have to come out as one piece, and it requires all of the manifold studs to be removed from the head. Not my favorite approach.

I also spent time coming up with a good stud/nut arrangement. I ended up choosing a fresh set of OEM studs, ARP 8740 12-point nuts with integrated flange/washer. Then I cerakoted all of them, which will hopefully prevent rust.
 

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Discussion Starter · #42 ·
I have an old log-style Toyomoto manifold. The turbo and manifold have to come out as one piece, and it requires all of the manifold studs to be removed from the head. Not my favorite approach.
I got some shorter studs so I can pull the manifold and turbo off without getting the studs out. But yeah it’s quite the pain in the ass. I’ve almost tipped over into the car trying to drag the assembly out several times. It’s the only manifold that happens to fit this turbo unfortunately. I’ve seen a iwg turbo tubular manifold for a Supra and there’s barely any space left next to the shock tower. It’ll definitely smash into the shock tower in the Lexus.

I expect some power loss with this manifold. Just nature of the beast. Depending on how good the spool is versus the power loss, I might weld up my own tubular manifold to fit the turbo car combo. The downpipe routing is the best thing about this manifold though. It’s so easy and so spacious. Only 2 45 degree bends and it lines up perfect with the rest of the exhaust. I also like how it looks in the engine bay but that’s just me.
 

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Discussion Starter · #43 ·
The coolant lines and oil lines are finally done. I had to add new coolant since I drained most of it for the coolant return line rework. I went with Prestone Platinum instead of the Toyota red. It’s compatible with HOAT anyways and the coolant in it right now is mixed red/green anyways. Most of it is drained regardless. I also changed the oil and added some in dye to it. The oil leak needs to get chased down. I’m pretty sure it’s the FMS. Hopefully it’s not both the front and rear main seals.
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I also added some aluminum heat shield backed by ceramic fiber, with fiberglass wrapping around it. Hopefully the fiberglass won’t melt.

Tried to start the car but it won’t fire. Fuel pump didn’t turn on. How I thought the relay was wired and how it was actually wired was completely different. The ground for it got removed during the wiring rework. I decided to run a new power line to the relay and used the Haltech as a switched ground. I’m pretty sure this is how it’s meant to be wired.

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The car cranked right up and idled perfect. Without the resonator, the exhaust wasn’t all that loud on the outside. However, it’s emoting a very low noise that’s especially noticeable on the inside. Some people like low, bassy exhaust but I hate it. It’s not that much worst than before but I have plans to get rid of it.

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At idle, the VE hasn’t changed much at all. Makes sense I suppose, it’s not that major of a setup change at low airflow. Vacuum is same as before so no (major) leaks most likely. One thing that’s changed quite a bit was transient throttle. It needed 50% more transient fueling to smooth out the response.

Still needs a lot of work before it can start rolling around again. It’s all small stuff but it adds up. The one major pain right now is the wiring still. The power steering reservoir and the wiring harness is occupying mostly the same space. I need to get another ecu enclosure from the junkyard as well as getting the PS reservoir to fit nicely somewhere.
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Discussion Starter · #44 ·
The UV dye was very helpful. Oil is leaking out of the rear portion. Probably rear main seal. There’s also some oil on the front edge of the oil pan. This one is confusing. Maybe it’s leaking from the corners of the oil pan. It doesn’t look like it’s the FMS or the turbo oil drain.
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I also took the car out for a few rips. Ignition timing is turned down and target boost is set to 100kpa instead of what I normally run. Rolling off from stop is worst than before but I haven’t been driving the Lexus for a while and my other car is very different clutch wise. I didn’t run it past around 4500rpm, just some light duty testing. One big surprise was how quiet the car was when on throttle. The recirculated wastegate really took the tone down. While idling and cruising around, the car is a little bit louder than before. Not a huge surprise since it has one less
resonator/muffler. The turbo still makes the typical spooling noises and the integrated BOV still makes a great amount of noise but a lot less than the TIAL BOV dumping to atmosphere.
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In terms of how the new turbo feels, it’s a lot better than before. In 3rd gear while the wastagate is held close, the old s362sxe spools the same as the new bigger EFR turbo. (Red is new, green is old in datalog) The turbo also know makes boost in 1st and 2nd gear at ~4000rpm. Before it would hit all at once around ~5000rpm and roast the rear tires. It’s much more linear more. (The old turbo had no pre-turbo leaks that I can see when I pulled it off). Transient response is also VASTLY improved. The engine doesn’t feel like it’s falling on its face every shift. Transient throttle fueling still needs work so it’ll only get better from here.
 

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Discussion Starter · #45 ·
It turns out a lot of the new drivability problem at low rpm was due to how the vvti was behaving. The previous PID settings were way to sensitive with the new setup and the angle would oscillate 20 degrees at low rpm. After that was improved, low speed is way better now. I also got around to tuning the mid boost part of the car and found some old data to compare to. Boost in 3rd gear is way better than the old S363 with like for like VVT targets. Another thing I noticed was that the wastegate on the new setup is opening WAY earlier. This means the EFR turbo can push more boost at lower rpm vs the
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I also tried to do some VVT tuning on the street. It’s a little janky since there’s so many uncontrolled variables but major changes gives consistent results. It’s good for having a rough map but a dyno is definitely needed for fine tuning. The car really likes ~30 degree of VVT under ~4500rpm WOT.
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The power steering reservoir still needs to get relocated. I bought the PHR fitting so that should make it much easier than weld, cut, reposition, re-weld. I also found out my fuel pump connector is melting a little bit. No more BoostAPump usage until I get a new connector. I’ll probably need to find a better solution for pushing 25 amps per pump.
 

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Discussion Starter · #46 ·
The PHR suction fitting got here. Unfortunately, the bolt only works in 1 of the 2 mounting holes for the inlet, the top one. This limits the fitting to two possible orientations which entirely defeats the directional adjustment nature. What’s worse is out of the two positions, only one location will let a hose through without going straight into other rigid components. It also puts the hose in a weird bend. I ended up making another mounting clamp out of a random piece of steel to use the other hole. Seems like an oversight in design to me given how easily and cheaply it can be fixed. A lot of this is specific to my setup and there isn’t really another option out there however.
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I will have to print a mounting bracket for that reservoir. It’s currently zip tied. The reservoir is from a Acura TL. Brand new for $15 from Dorman and works great. The stock one was pouring fluid out the top, through the cap. Not sure how that works.

Without the annoying whine from the steering pump, the car is way quieter at idle. Comparable to some stock cars. The drone from 2600-2900rpm however is still horrendous and atrocious.

I had an issue with the boost control solenoid. Mostly a plumbing problem. The pierburg 3 port works opposite of how I expected it to. 100% duty cycle means air is vented and 0% means air not vented. My MAC 3 port and most EWG is plumbed the opposite way. Just switching the ports also doesn’t work. Well it does but it’ll overboost due to how I’ve plumbed It.
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I’ll have to crawl under the car to access the IWG actuator and a line to the bottom port. Alternatively, I can poke a hole in the line to the top port and that’ll also work but I don’t think that hole will give very consistent results with regards to duty cycle over the operating range of the car.
 

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Discussion Starter · #47 ·
The new air filter got here. It ended up being too long to fit. I’ll have to redo the intake pipe at some point to get the filter to fit. For now, the spectre filter will be fine.
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I went to a junkyard to grab a ecu box. It ended up not fitting in many ways. Even with angle grinding, it’s not going to work with the XS Power FFIM. And despite all the wiring rework, the harness is still too clunky, stiff, and massive to get a good mounting spot for the ecu. So, I ended up chopping the parallel harness from Haltech off and doing a lot more wiring changes.
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Creating a spreadsheet with where everything is was absolutely necessary to keep track of everything. It’s was quite the pain to dig through the wiring diagrams but it was worth the effort.
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For now, connectors EA2 and EA3 are completely gone. There isn’t any more wires to pull at this point. I also happened to weigh all the wires I yanked out. It was barely 700grams, though I didn’t pull any wire that passed through the firewall. Not that weight reduction matters all that much anymore.
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Discussion Starter · #48 ·
The center console where the shifter sticks up into was mostly open to the element. I used some CLD butyl rubber sheets and Mylar bubble wrap to help with insulation. Thermal-wise it worked great but a lot of noise still comes through. I got some closed cell foam insulation and a generic rubber boot to close up shifter hole.
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It removed so much noise that it felt like my ears were stuffy/congested. The clacking of the transmission, clutch, wind noise, and etc was practically all gone. What wasn’t gone was the drone. However, it did seem to help a little bit, and the spectrum output from Audacity seemed to indicate a 2-3 db drop around the drone zone though what that translates to in term of actual measurements, I don’t know. I was still missing a trim piece for the shifter so I went to a junkyard to grab something for it. I also grabbed a gs300 ecu box, hoping that it would fit. The ecu box experiment was a failure since the is300 ecu was wider than the gs300 one but the actual problem was the oil dipstick and DBW throttle is competing for space where the ecu box attempts to sit. The gs300 ecu box should be a little more compact vs the stock one so it looks like I’ll need make something to mount the ecu instead. The shifter trim piece worked out great though. I’ll need to make some covers for the missing buttons but that’s easy enough
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I also finally made a mount for the power steering reservoir. Worked out pretty well, it clears the hood and injector harness. I actually make the clamp/bracket severely undersized due to me using my thumbs to guess the diameter. It’s probably 5-10mm off. The adapter I made to avoid reprinting it then made the thing oversized by holding it open more than necessary. Still works, not great but meh.
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The roof of the car had some clear coat peeling in the front portion. I got some paint and clear to cover it up. I had to sand the paint to get rid of the bad clear coat first. I also had to scuff up the rest of the roof to get the new clear to stick.
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Just that tiny portion of the roof required a full can of base coat but the entire roof used only a can of clear. After about a day of curing, I did some light wet sanding to reduce as much orange peel as I cared to.
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The paint after some polishing action came out looking pretty okay. From 10 feet, it looks factory and I don’t care enough to make it better than that.
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Another minor thing was a new antenna. the old one was dry rotted at the base. even though I don’t have the radio hooked up, I liked the look of the antenna.

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Discussion Starter · #49 ·
Finally got this bad boy. Still not hooked up yet and haven’t finalized a position to mount it yet either. I want it to be prominent but not in your face.
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I have to admit I was expecting the Borg Warner EFR’s recirculating BOV to be quite quiet. It turned out to be louder than my dump to atmosphere Tial 50mm BOV for some reason. I think the main problem is that it’s having some compressor surge problems. It’s making the stututu sounds rather than the pshhh sounds. (Very scientific and descriptive…). In a hilarious contrast to the fake BOV noise generator, I ended up making a Helmholtz resonator for the intake to suppress the real BOV.
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The Helmholtz resonator is 3d printed out of ASA. Not very pretty but it’s a prototype. I also used very common tube dimensions so making one out of metal would be easy. (1.5” diameter for the chamber. Target frequency is 330Hz) As to whether or not it works, I’m not sure. I’ll need to record some audio on a road I’ve previous recordings off to make an actual comparison. In terms of subjective analysis, it seems to be working a little bit. The sound of the BOV seems to quieter on the 2nd and 3rd pulse of the “stututu”.
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I also added a turbo speed sensor finally. It’s practically mandatory with the EFR series. I don’t expect to reach the rpm limits but boost leaks are a thing. Immediately after viewing a few logs with the turbo speed sensor (TSS) I got concerned with boost leaks. Given the gauge pressure at the intake manifold (if they were correct) the turbo was over spinning for the expected mass flow by quite a bit (3-5k rpm). Had to make a boost leak tester out of some 3” ID pressure rated PVC caps (which are ~4” OD). I was only able to test from turbo to throttle body opening due to having to use a bike pump. Found a few minor leaks like a pinhole where I welded the IAT sensor bung…and at the TSS where the wires were coming out… unfortunately I was only able to test to 15psi before the pvc cap blew off. I tried to seal the TSS with some RTV which is why there’s painters tape around it in the pic above. Unfortunately I don’t think anything will stick to that wiring sheath.
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My model year (05) had a threaded PCV. I know it’s not 1/2 npt ( and why would it be anyways) although it’s very close and it was what I was using before. I purchased a m16x1.5 banjo fitting after doing some measurements. I don’t know if it’s suppose to be m16x1.5 or some other thread size that’s practically identical but it fits perfect (in my car at least). It did require a number of copper washers to fit with the hose but it’s not under any real pressure. It cleaned up the routing a lot.
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I also moved the horns from the front to the sides. A very minor thing but I’m planning to mount the fake BOV thing up front and I didn’t want to block too much of the airflow.
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Speaking of airflow, I also starting on making a funnel/ram air inlet where the hole next to the fog lights are. I’m not covering the entire inlet up since I don’t know if the fog light housings need the cooling. It’s still in the prototype phase but it’s already very close. It’s hard to see but there’s an unused mounting tab in there as well for some reason. It’s sized for a 1” ID hose since that’s what I’ll be using. (I wonder if I can attach solidworks and STEP files here) the inlet is for fresh air directly to the air filter. It can also be repurposed for the brakes if I ever felt the need for additional brake cooling.
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I managed to find a 4” stainless cap on Amazon to speed up the fab for the exhaust Helmholtz resonator. It’s a lot beefier and heavier than I thought given how cheap it was. It’ll be a nice surface to weld a hanger to though. No need to worry about melting the thin exhaust tubes. I’ve done the basic calculations to size the resonator. I’m assuming that the exhaust gas will be somewhere around 100-125C ( where the resonator. Not post turbo obviously). Hopefully that’s not far off since EGT will change the resonant frequency by quite a bit. The good thing about a Helmholtz resonator (HR) as opposed to a 1/4 wave resonator is that the HR more of a band pass filter than a notch filter like the 1/4 wave. Also in contrast to the 1/4 wave resonator, a HR only works at one frequency band. The 1/4 wave resonator works at the fundamental frequency and every harmonic thereafter. I’m rather a fan of the higher frequency sounds of the engine and just want the drone gone.
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I also got a little resonator. The diameter of the body is 4” which should fit versus the old (and out of the car) vibrant ultra quiet which was 6” at the widest. The vibrant needed just a tiny bit of clearance to not touch the driveshaft so this should work.

There’s also a tiny issue with the power steering reservoir that’s entirely on me. I used heater hose for the return line.Heater hose and ATF does not mix. ATF is seeping out along the entire hose slowly. I can’t even say it was just to make it work. I had power steering hose when I installed the PS reservoir. I still have it. Need to change it out at some point.
 

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Discussion Starter · #50 · (Edited)
Made some more progress on the fog light intake (inlet? Not sure what to call it) It fits pretty well right now. It’s printed in vase/spiral mode so the slots for the bumper and the hole for the bolt has to be manually added in.
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It doesn’t sit very flush where it’s suppose to mount however so I ended up creating another version with the holes and slots in the model this time. It sits much more flush with the mount this time. Unfortunately I made a minor mistake with the dimensions so it’s a little skinny.
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It’s a very minor fix. I forgot to double a dimension. What’s not going to work however is printing the additional features but that’s entirely due to my setup. My 3D printer doesn’t have a parts cooling fan and I don’t intend on ever adding one so small parts come out very blobby. The vase/spiral print is much nicer and feels much stronger. I think the bad print has a wall thickness of 2.4mm vs the 2.0mm of the single wall vase mode print. (Though that’s easy enough to change). The only bad thing about the vase mode one is that the printer spends more time waiting for the layers to cool then actually printing.
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Link to CAD/STL files if any one wants them: IS300 Fog Light Air Inlet by rbkUE8nK4Y8T
 

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I am curious, why are you making the inlet diameter so small? It looks like you have a lot of room so why not make it bigger.

Depending on the shape if it is too small the air can build up in front of it instead of flowing through it.
 

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Discussion Starter · #52 ·
I am curious, why are you making the inlet diameter so small? It looks like you have a lot of room so why not make it bigger.

Depending on the shape if it is too small the air can build up in front of it instead of flowing through it.
I’m using a 1” hose since that’s what I had. The inlet diameter is very easily changed anyways. The length is determined by clearance to my intercooler piping.
 

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Discussion Starter · #53 ·
More minor updates.

I made another version of the fog light inlet with a 2in hose outlet. With my car at least, the passenger side is a no-go but driver side is fine. This is mostly to shove cold air to the air filter in an attempt to increase efficiency. IATs are perfectly fine as is. They are only 3-5C over ambient at full boost but making the car work less hard for the same horsepower is always a good thing in my opinion. I could always repurpose this as a brake cooing duct.
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I also did some leak tests on the BOV/BPV. It did have a leak, albeit a small pinhole one where the 1/8 NPT barb threads in. A little RTV later and it's fine. I was half hoping that the small leak was responsible for the turbo flutter sounds. I could not tell if it made a difference or not. From a bunch of googling though, it seems that the EFR's integrated BPV is just prone to make the "Stututu" noises rather than a clean "Pshhh."

The waste gate actuator preload also got changed. Turbosmart recommended a 1mm preload and that's what I used. I had a lot of problems with the turbo "overboosting" then drop to just above gate pressure when the boost controller starts doing its thing. I had to hold 100% duty cycle after the boost peaks just to get the pressure to climb. If I let off and go WOT again, the pressure usually reaches target unlike going WOT from lower rpms. After a lot of googling over weeks, I ended up adjusting the preload to 2.5mm. It's behaving much better now. The boost controller actually held target steady in 2nd gear which I never managed on the old S362 ( it apparently was not a S363SXE like I thought but a S362SXE and specifically a 8380). It's quite hard to find people's experiences on internal wastegates since most just go for EWG. I'm still a fan of the packaging and noise advantages of the IWG setup despite the troubles so far.
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Discussion Starter · #54 ·
Had an unfortunate encounter with some highway debris (how the hell does someone just drop a crash bar/bumper support?) right before a freeway exit. I was going too slowly to swerve into an open lane and didn’t want to do heavy braking since I don’t trust people not to rear end me. So I lined it up and went right over it. Some of it hit the bumper and the bits that went below hit the exhaust. Took the exit and dragged it 3 blocks home…
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After a session with the plastic welder, the bumper is mostly fixed. I did manage to lose the tire air deflector though. It’s about ~$25 online and took me a solid 30minutes to find since the manual listed it as a “pad” for some reason. I’ll just make my own. Scrap plastic sheets are basically free. I hope polycarbonate will hold up in this application.

The exhaust will take a little longer to fix. There’s a leak where the exhaust band clamp is. It’s a simple dent that’s easy enough to fix but I’ve been meaning to redo my exhaust setup anyways. Finally putting the tiny resonator to use.
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It also allowed me to reuse my vibrant ultra quiet. The bottle resonator pushed everything back enough that the vibrant now clears the driveshaft. There’s a metal bar welded to the bottom of the vibrant for skid plate purposes. The car is 1” lower (I think) but that’s enough to scrape the driveway every time.
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I did fire the car up with only those two resonators connected. I thought for a second that it might be enough to make it work. It’s definitely not unfortunately. Though to be fair it’s only a bit louder than the big oval muffler. It’s quieter than most IS300s running around with modified exhaust (that I’ve seen at least). I might be able to make it work with a Helmholtz resonator and 1/4 wave resonator. Speaking of the HR, it’s coming along finally. 4” chamber with 2.5” neck. Length still TBD depending on space constraints
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The car is also having other issues. The thermostat is dead and I’m almost certain that there is a boost leak somewhere. Either there’s a boost leak or there’s a 7-10 psi drop across the intercooler… I’ll be welding bungs for pressure sensors/thermocouples on the intake pipes so I suppose I'll find out. Obviously, I will try to find boost leaks as well. The car is also refusing to heat up to full operating temp. I thought it was because of the 55F ambient but it’s been 75f last few days and it’s still running 65-70C after normal driving. It normally hits 75-85C.

On a positive note, the additional wastegate preload has helped a lot in controlling the boost boost. The boost actually picks back up to target after the initial dump. With 160kpa in 4th gear, it’ll do 60-80kph in 1.3-1.4 seconds. But it’s still off from the previous setup with a 1.1-1.2 (though that was with 170-180kpa).
 

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Discussion Starter · #55 ·
The exhaust is finally back in one piece. I ended up welding a 1/4 wave resonator while I was there even though I was initially hesitant to do so. The length I came up with was somewhere around 26.5" to target drone at ~2750rpm or ~133Hz. I'm still planning on Adding a Helmholtz resonator. The 1/4 wave took care of a lot of the drone but there's still quite a bit left and right of 2750rpm.
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I reused the old Dynomax muffler that was always in the car. No sense in buying something else. The exhaust ground clearance is also slightly improved now. There's still maybe 1" or so of ground clearance I could reclaim if I really tried.
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The drone around 2750rpm is dramatically lessened. Not really a surprise. 1/4 wave resonators aren't exactly magic. However, there is still a large annoying drone with a frequency of ~120Hz and ~140Hz. The 1/4 res is also a little long. It seems to be around 129Hz rather than the target 133Hz. It's easy enough to chop a portion off and make it adjustable to get the length just right. Even with it being slightly off, the improvements are very noticeable.
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My decision to reuse the dynomax was rather sub-optimal as I've found out. The new turbo setup with this muffler creates a staggering amount of drone at idle. I can't really hear it inside the car but on he outside, it's pretty bad. There's a giant peak at 94-98Hz and another one ~49Hz. A 1/4 wave res for 49Hz will be ~71". That won't be easy to fit. I could target the 98Hz instead but a 1/4 res at 49 Hz will work at 49,98,147, and so on with decreasing effectiveness. Interestingly enough, with only the vibrant ultra quiet on, there is no peak at 100Hz whatsoever. I bet if I swap out the big dynomax, the 98Hz spike will be gone.
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I still plan on adding a Helmholtz resonator. Tentatively, I'm going to target the 120Hz area which is around 2500rpm. That's a large portion of my cruising rpm. Made a quick,little plot to reference the dimensions I will need rather than googling the Helmholtz calculator every single time. This assumes EGT at the HR is 150F which I'm pretty sure is a little low for where I plan to put it.
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I think I'll swap out the big dynomax muffler for something else before sizing the HR. No sense in building one for 120Hz if a new muffler solves that drone band.
 

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Discussion Starter · #56 ·
Back to the more exhaust work. I’ve had one of these bad boys sitting around for a little while. To the untrained eye, it looks exactly like a generic espresso puck screen. I prefer to think of it as a plate with very small perforated holes.

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After eyeballing a convenient location along the exhaust, I drilled out a hole that’s fairly smaller than the espresso puck. 38mm in my case. The brown sludge is solar flux B. I don’t have the equipment to backpurge so this is a good replacement for that. It doesn’t mix all too well with isopropyl so I’ll probably have to try methanol next time. It seemed to work well enough in this case though.
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I don’t have a picture of it fully welded up but just imagine a full weld around the screen to the exhaust pipe. The screen melts very easily. 30amps is enough vs 50+ for the actual exhaust pipe so I had to “pre-bead” the edges. It’s also why I used a 38mm hole instead of something closer to the size of the espresso puck screen. That’s all there is to this exhaust mod.

If you thought that this is stupid and won’t do anything or cause an exhaust leak, you’d be wrong.

Using the same phone as before in roughly the same place ( 1-2” difference in position maybe), there’s an enormous change in the exhaust note. The first one is the espresso puck screen+ 1/4 wave resonator. The second one is the 1/4 wave resonator only. Both runs are ~2000-3000rpm, the cruising and drone range, and both runs are at operating temps.
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The espresso puck screen shows a solid -6dB from 118-135Hz. That’s the meatiest and most annoying band for drone during cruise. The difference below 2300 and above 2800rpm is minimal but thankfully the exhaust isn’t very loud outside this range.

To my surprise, Google yielded no results of people trying to use espresso puck screens as resonators. As much as I would like to be the first one to come up with this concept. The concept here is neither novel nor new. A plate with very small perforated holes is just me trying to not say that it’s a micro-perforated panel (plate) or MPP for short.

A espresso puck has many micro-perforations with mine having a mesh size of 100 micrometers and fairly thick at 1.7mm, which should help it survive exhaust gas. It’s also supposed to be 316 stainless (it is an espresso puck after all so lots of water contact and no one has indicated rusting yet). So it stands to reason that an espresso puck would work as a MPP resonator. And the data indicates that it does. Subjectively, it also works which adds validity to the data.

As great as this is, longevity of this solution is still unknown. And while it performed very well, it is still fairly suboptimal. The position of the “Espressonator” involved me eyeballing roughly 75% back from the turbo. The MPP (and the 1/4 wave resonator) works best at the anti-node of the target frequency. I have no idea what frequency the MPP is targeting. That being said, it’s not horrendous sensitive. Adding more would also help. GM uses 3 in quick succession and two sets of them per exhaust pipe. Yeah, like I said, not a novel nor new idea.

Just a side note if it isn’t clear, using a MPP as a resonator in an automotive exhaust is patented by a OEM supplier. While you could in theory patent something something similar but different enough to warrant a new patent, plainly commercializing this will probably run you afoul of a multibillion dollar company.
 

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Throw a flowmaster on in the stock location and it a day bro- the super 10 or 44 would be a little loud but the original one would work good with a straight thru resonator or 300 cell race cat - chambered muffs kill some power but adding power on a turbo car is not difficult- seems like your making a simple thing really hard haha
 

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I’ll probably need to find a better solution for pushing 25 amps per pump.

The new air filter got here. It ended up being too long to fit. I’ll have to redo the intake pipe at some point to get the filter to fit. For now, the spectre filter will be fine.
Somehow, I've not been keeping up with this thread... Some cool info here.

I don't know how you've got your fuel pump wiring arranged, but you need 12AWG for the big pumps that can draw 25A. And be careful on connectors, because not many can handle that kind of current. For mine, I chose the Delphi Metri-pack GT280 series, which are rated for 28 amps.

Regarding your air filter... If you're willing to ditch your passenger side foglamp, you can fit a really big filter in the cubby between your inner fender liner, chassis, and front bumper cover.

Take a look at post #58 in this thread for more detail:

Throw a flowmaster on in the stock location and it a day bro- the super 10 or 44 would be a little loud but the original one would work good with a straight thru resonator or 300 cell race cat - chambered muffs kill some power but adding power on a turbo car is not difficult- seems like your making a simple thing really hard haha
I think it's pretty clear our OP enjoys geeking out on the exhaust note - and sounds in general that his car makes.
 

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Discussion Starter · #59 ·
Throw a flowmaster on in the stock location and it a day bro- the super 10 or 44 would be a little loud but the original one would work good with a straight thru resonator or 300 cell race cat - chambered muffs kill some power but adding power on a turbo car is not difficult- seems like your making a simple thing really hard haha
I wouldn’t call upwards of 50+hp loss a small amount. Efficiency is the name of the game. And this endeavor so far has been fairly basic. I didn’t have to use any math beyond simple algebra and even then i googled most calculators I needed.

The only comprises I want to make with this exhaust is for clearance and cost. So far, it’s as loud as a stock mustang/Camaro (v8 that is) at idle (I can get it even quieter without obstructing the flow path). It’s probably as loud (or quiet depending on how you look at it) as a stock mustang/Camaro at cruising as well. It’s much, MUCH louder when I get on it. It’s a straight through exhaust after all.
 

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Discussion Starter · #60 ·
Somehow, I've not been keeping up with this thread... Some cool info here.

I don't know how you've got your fuel pump wiring arranged, but you need 12AWG for the big pumps that can draw 25A. And be careful on connectors, because not many can handle that kind of current. For mine, I chose the Delphi Metri-pack GT280 series, which are rated for 28 amps.

Regarding your air filter... If you're willing to ditch your passenger side foglamp, you can fit a really big filter in the cubby between your inner fender liner, chassis, and front bumper cover.

Take a look at post #58 in this thread for more detail:



I think it's pretty clear our OP enjoys geeking out on the exhaust note - and sounds in general that his car makes.
Nice Provent 200 you got there. Those 1” hoses were suck a pain to make work.

Regarding the fuel pump connector, it turned out to just be some shoddy crimping on my part that caused the connector to melt. Though the connector itself I’ve found out is quite beefy. It’s the Aptiv Apex 2.8. The sealed version that I’m using is rated for 25A with 12gauge. There’s is an unsealed version for accepts 10 gauge and is rated for 40A.

If I pushed the pump to the max, it’ll pull 22.8A max at 20V, not sure how much over that I should size the connector for. I don’t plan to push it that hard but I’m sizing for worst case. I suspect I’ll be fine now that I’m using 10 gauge wires and really made sure the crimps are good this time. I’d probably rewire the entire thing with 12 gauge ptfe wires. The 10 gauge gxl wires are chunky and stiff.

Unfortunately cutting a 4” hole for the intake is not something I want to do. It’s a hell of a true cold air intake though. And while the filter “doesn’t” fit, it’ll fit with some re configuring (probably).

Acoustics is not something I’m versed in. But getting the sound just right required me to do a little more than just swapping out mufflers and hoping for the best. The tires are as loud as the exhaust during cruising right now (though to be fair, they are 200TW tires) and I plan on making it quieter still. The car can wail all it wants at WOT.
 
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