Builds "Rednexus" - 2007 GX470 Build and Fabrication Thread (10 Viewers)

[Rednexus]

Since the exhaust and injector issues are (fingers cross) sorted for my GX, I finally upload the 87 octane Active Duty YotaWerx tune this morning. Initial impressions are that the midrange torque/throttle responsiveness are improved, full-throttle seems about the same. The difference is there but not dramatic, although I'll need to put some more miles on it to finish the ECU learning process. I was worried about how the transmission tune would play with my Nomad valve body, but they seem to work fairly well together. It definitely holds gears even longer than before (in a good way).

I bought the OBDII to USB adapter and a VF Tuner license allowing me to DIY change tunes and experiment. The actual tune process was really easy and took maybe 15 minutes. We have a camping trip planned later this month so I'll see how much towing is improved. I'll also try the 91 octane tune sometime in the future.

 

[BigNick]

For rock protection, you could have a muffler shop remove the rear resonator and add in a turndown in the similar location as the Magnaflow. That should be a $50-100 job and would provide more clearance.

Reviews on the Magnaflow are all over the place....some say zero drone, others say it's unbearable.

Tbh, I love how it sounds.. sounds like v8 power no matter where and is not unbearable to me. And what's more if I want to hear something else, Mr Levinson has something to say.

 

[Rednexus]

Tbh, I love how it sounds.. sounds like v8 power no matter where and is not unbearable to me. And what's more if I want to hear something else, Mr Levinson has something to say.

Drone/sound is super-personal and varies person-to-person. The 55 mph drone on my Borla drove me crazy, but didn't actually bother my wife that much.

I put around 150 miles on the GX today with the tune/Dirty Deeds exhaust. Now that things are getting settled it's really, really fun to drive. Midrange power has definitely improved and it pulls really well. It also downshifts less on the highway. Between the better midrange, throttle response, and sound, it actually feels quick.

Sound wise it is louder at lower speeds but pretty non-intrusive and quiet cruising. I forgot it had an exhaust at 75-80 mph on the interstate. With the less-deep tone of the Dirty Deeds, the added low-speed volume is less annoying than the deep drone of the Borla.

The tune did have some weird behavior when I used cruise control - which seemed to be transmission related. I'll see if it goes away and it not reach back to to YotaWerx, as it seems likely that it's due to my Nomad valve body (they indicated the transmission tune was easy to adjust remotely and they'd be willing to do such).

 

[McDuff123]

Drone/sound is super-personal and varies person-to-person. The 55 mph drone on my Borla drove me crazy, but didn't actually bother my wife that much.

I put around 150 miles on the GX today with the tune/Dirty Deeds exhaust. Now that things are getting settled it's really, really fun to drive. Midrange power has definitely improved and it pulls really well. It also downshifts less on the highway. Between the better midrange, throttle response, and sound, it actually feels quick.

Sound wise it is louder at lower speeds but pretty non-intrusive and quiet cruising. I forgot it had an exhaust at 75-80 mph on the interstate. With the less-deep tone of the Dirty Deeds, the added low-speed volume is less annoying than the deep drone of the Borla.

The tune did have some weird behavior when I used cruise control - which seemed to be transmission related. I'll see if it goes away and it not reach back to to YotaWerx, as it seems likely that it's due to my Nomad valve body (they indicated the transmission tune was easy to adjust remotely and they'd be willing to do such).

Really glad you’re enjoying the DirtyDeeds exhaust. I installed one about 2 years ago, and agree with everything you mentioned…low-RPM sound is throaty, classic V-8 yet there is no drone on the highway.
Keith at DD is the man…probably knows more about these engines and flow characteristics than most.
Someday I’ll hit you up for pointers on the headers and tune!

 

[Rednexus]

Really glad you’re enjoying the DirtyDeeds exhaust. I installed one about 2 years ago, and agree with everything you mentioned…low-RPM sound is throaty, classic V-8 yet there is no drone on the highway.
Keith at DD is the man…probably knows more about these engines and flow characteristics than most.
Someday I’ll hit you up for pointers on the headers and tune!

I think it was you and/or someone else on another thread talking about how great the DD was....some more research on Tundra forums confirmed it as well, so that is the direction I went! It's interesting that a small shop like Keith's can make a muffler like that in-house that sounds better than Borla, Flowmaster, etc make.

My wife finally rode in it today - didn't really notice the difference much (which is positive). My 5-year old loves the new sound. The big test will be how annoying it is or isn't towing, when the sound bounces off the front of the camper and back into the rig.

 

[DRANGED]

With your stubby downturn before the axle I bet there won't be much echoing back..

 

[DRANGED]

Thanks for the advice! Although the rocks are starting to pound on my tailpipe.

Shorten that puppy up!

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[Rednexus]

With your stubby downturn before the axle I bet there won't be much echoing back..

I set up the tailpipe with a slipjoint to allow the Borla tip to come off and a turndown to easily go in and direct exhaust off to the side (similar to the Magnaflow Overland). I ran it with the old Borla a time of two off-roading and it was actually a bit louder, but didn't tow with it. Will try it both ways with the camper and see how it works!

 

[Rednexus]

Hit up a short and sweet local trail today. The video does not do it justice. It's super steep and washed out. 3 years ago I could take a Subaru up it, now it requires a real 4x4. Also still loving the Dirty Deeds exhaust. Adds another dimension to wheeling.

 

[Rednexus]

Towed our camper ~220 miles this weekend. Regarding the tune....wow...way more power pulling the camper up hills. We took some crazy steep and twisty highways (15%+ grades in places) and I never once wanted for more power. It pulled like a freight train in 2nd or 3rd gear at 3000-3500 rpm. Even my wife remarked that the hills weren't bogging down the rig at all. Low-end torque (1500-2200 rpm) is really about the same as before, maybe a bit better. Now it has extra power on tap when revved. Gas mileage was 13 on the way out and just over 12 on the way back, which was about the same as normal.

Regarding exhaust noise, the Dirty Deeds is better than before but didn't solve the fundamental problem of sound bouncing off the front of the camper with a rear exit exhaust. So it's still louder than ideal towing. Since I have a slip joint at the back I'll build a 90-degree side exit piece for towing use. I ran the turndown but it just bounced sound off the road and back up instead.

 

[Rednexus]

Made some more exhaust tweaks today. I'd love to say this is the last but now that I have all of these fabrication tools it probably won't be .

First off was removing the Helmholtz resonator I had built before in near the end of this tailpipe. This resonator had a 6" long 1.5" O.D.. neck and a 5.875" long 4" O.D. chamber. It was targeted to ~130 Hz and did a great job cancelling that frequency but not much at all for lower frequencies. The Dirty Deeds has a integrated quarter-wave resonator that's also tuned to this frequency, so it really wasn't doing anything, and I was getting the small (but not insignificant) drone from 1,500-2,100 rpm or so (around 117 Hz).

Although it's been almost 20 years since I finished my last college physics course, I did have a theory that the overall design of the Helmholtz was not the best as it used 1) a neck that was too long and narrow and 2) too small of a chamber. I think the long/narrow neck just doesn't allow for a lot of sound attenuation for a bigger engine like a V8....it might cancel out some of the frequency but is limited in how many dB it can reduce. So I played around with the Helmholtz spreadsheet and built a new version that was 9" long (4" O.D. chamber) with a shortened 4" (1.5" OD) neck. This was tuned right to the 117 Hz drone I was having. It was also the absolute biggest I could fit in this area - and had almost no clearance between the rear AC lines, exhaust hanger, frame, and fender. I had to install it at a weird angle to get it to fit.

After installing - wow, huge difference. Cruse at 70 mph is now 57 dB or so - basically stock quiet on the highway. At light throttle it's almost always below 60 dB, but you do hear a faint V8 rumble in the background (more pleasing sound that stock). 55 mph (~1,700 rpm) is ~62 dB, so a tiny tiny drone but maybe 2 dB louder than stock. Very, very happy with how this turned out. It did reduce some of the rowdiness of the Dirty Deeds sound, but it still sounds mean and fairly aggressive above part throttle (can obviously tell inside and out the exhaust is not stock). It still sounds better than the Borla I had. If I do want some sound back for some reason., I can pull off the Helmholtz and add a solid plate over it in around 10 minutes.

I also built a rear 90-degree piece to shoot the exhaust straight out the side of the GX for use when towing to reduce the sound bounding off the front of our camper. I sliced up a 90 degree and 45 degree 304 SS elbow to make this - fabrication skills are not great but improving. Having the much nicer Hobart welder helps too.

And I still have my turndown for improving clearance when off-roading.

For anyone else who reads this and is considering a Helmholtz, I'd suggest going with an even bigger tube neck (say 2" O.D.) and chamber (say 5" O.D.). This would make for a bigger resonator but provide more attenuation.

 

[HomersCanyonero]

Hit up a short and sweet local trail today. The video does not do it justice. It's super steep and washed out. 3 years ago I could take a Subaru up it, now it requires a real 4x4. Also still loving the Dirty Deeds exhaust. Adds another dimension to wheeling.

I can hear the exhaust on this video.

 

[Rednexus]

I can hear the exhaust on this video.

It's a bit quieter now but still there .

Threw this on as a trial tonight. Made it even quieter - didn't exceed 60 dB other than half-throttle. Should make long hauls with the camper more pleasant as the exhaust shouldn't boumce back into the cabin. But it will come off right after since it's kind of ugly.

 

[HomersCanyonero]

It's a bit quieter now but still there .

Threw this on as a trial tonight. Made it even quieter - didn't exceed 60 dB other than half-throttle. Should make long hauls with the camper more pleasant as the exhaust shouldn't boumce back into the cabin. But it will come off right after since it's kind of ugly.
View attachment 3412811

Nice job improving your welding skills to be able to play around with the muffler sounds….im sure you’ll figure out a more aesthetically pleasing solution….I’ve always liked the exhaust coming through the side bumper…but that’s just me

 

[Rednexus]

I'd been having some issues with rear brake noise recently, which I finally isolated to the parking brakes. I pulled the rotors and cleaned the brakes, only to have the issue re-appear. So tonight I pulled them off and found they needed some more adjustment, and that one of the retaining springs/clips had failed. Pretty easy fix, and now the parking brakes work perfectly.

But....when I pulled off the DS rear tire, the entire inside of the wheel and outside of the backing plate were soaked in brake fluid. I had pulled our camper around 135 miles yesterday and noticed an odd smell (almost like burning rubber) that I couldn't isolate. This must have been it. The leak was coming from one of the PowerStop SS lines, at the fitting between the SS line and hard line going into the caliper. I had pulled the calipers when I initially pulled the rotors and cleaned the parking brakes, so that must have caused a failure in the line (which should not have happen as I worked not to kink it). I called PowerStop and filed a warranty return.

Super glad I mis-adjusted the parking brake the first time and had to pull the wheel off tonight, or I might not have noticed this until the brake light turned on. Also very glad I didn't lose brakes while towing yesterday. Hopefully PowerStop comes though and overnights me a new line under warranty, since the GX is now an ornament in my driveway.

 

[aztoytec]

Wow.. good catch. That could have been really bad especially towing!

 

[HomersCanyonero]

I'd been having some issues with rear brake noise recently, which I finally isolated to the parking brakes. I pulled the rotors and cleaned the brakes, only to have the issue re-appear. So tonight I pulled them off and found they needed some more adjustment, and that one of the retaining springs/clips had failed. Pretty easy fix, and now the parking brakes work perfectly.

But....when I pulled off the DS rear tire, the entire inside of the wheel and outside of the backing plate were soaked in brake fluid. I had pulled our camper around 135 miles yesterday and noticed an odd smell (almost like burning rubber) that I couldn't isolate. This must have been it. The leak was coming from one of the PowerStop SS lines, at the fitting between the SS line and hard line going into the caliper. I had pulled the calipers when I initially pulled the rotors and cleaned the parking brakes, so that must have caused a failure in the line (which should not have happen as I worked not to kink it). I called PowerStop and filed a warranty return.

Super glad I mis-adjusted the parking brake the first time and had to pull the wheel off tonight, or I might not have noticed this until the brake light turned on. Also very glad I didn't lose brakes while towing yesterday. Hopefully PowerStop comes though and overnights me a new line under warranty, since the GX is now an ornament in my driveway.
View attachment 3426860
View attachment 3426862
View attachment 3426861

Keep us posted if the warranty claim works in your favor.

I replaced all my brake hardlines and softlines with Toyota oem….just because they were 20 years old. Kept the old ones as spares.

 

[Rednexus]

The hose is O.O.S. with PowerStop until 9/20. I can get a new rubber one from NAPA for $28 tomorrow as a temporary stop-gap. I requested that PowerStop reimburse me for the stop-gap hose; we'll see if they do (if not I'm scratching their brake rotor/pad upgrade from my list and will get it from someone else).

Regarding the hoses, I originally had a OEM hose go bad in the front after swapping a caliper (must have gotten pinched), so I replaced everything with the PowerStop kit on the presumption that they'd be tougher and longer lasting than the 14-year old OEM-style rubber hoses, and that the braking performance would be improved. Plus the kit was only $90 from RockAuto, and I got it overnighted to get my rig back on the road. In hindsight, I would have just ordered all OEM hoses (as @HomersCanyonero did), but from Partsouq to save on the cost. The SS lines didn't make an appreciable difference in brake pedal feel/power. Unfortunately I had pitched the old ones too - should have thrown them in the old parts pile in the shed.

EDIT: PowerStop is not wanting to play ball on the nominal $28 credit, plus a replacement SS line, based on me needing to buy a the stop-gap temporary hose due to it being OOS for a few more weeks. Maybe they'll come around, but if not I'm not going to spend a bunch of time arguing back and forth with them over $28. Instead, when I do get around to a GX460 brake upgrade, I'll try a set of Aussie DBA kangaroo pad rotors and EBC green pads instead.

 

[RG7]

Man that’s a really good save. Glad you caught it when you did

 

[HomersCanyonero]

The hose is O.O.S. with PowerStop until 9/20. I can get a new rubber one from NAPA for $28 tomorrow as a temporary stop-gap. I requested that PowerStop reimburse me for the stop-gap hose; we'll see if they do (if not I'm scratching their brake rotor/pad upgrade from my list and will get it from someone else).

Regarding the hoses, I originally had a OEM hose go bad in the front after swapping a caliper (must have gotten pinched), so I replaced everything with the PowerStop kit on the presumption that they'd be tougher and longer lasting than the 14-year old OEM-style rubber hoses, and that the braking performance would be improved. Plus the kit was only $90 from RockAuto, and I got it overnighted to get my rig back on the road. In hindsight, I would have just ordered all OEM hoses (as @HomersCanyonero did), but from Partsouq to save on the cost. The SS lines didn't make an appreciable difference in brake pedal feel/power. Unfortunately I had pitched the old ones too - should have thrown them in the old parts pile in the shed.

EDIT: PowerStop is not wanting to play ball on the nominal $28 credit, plus a replacement SS line, based on me needing to buy a the stop-gap temporary hose due to it being OOS for a few more weeks. Maybe they'll come around, but if not I'm not going to spend a bunch of time arguing back and forth with them over $28. Instead, when I do get around to a GX460 brake upgrade, I'll try a set of Aussie DBA kangaroo pad rotors and EBC green pads instead.

I hope the do you good at least with the warranty. you can always carry the Napa one as a trail spare.

I did get my brake hoses from partsouq…it’s a benefit when you can replace them at your own timeline as preventive maintenance rather on emergency.