Doug Thorley headers for 5TH Gens

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Now that you guys have had your Doug Thorley headers on, any issues? Have you had to smog your 4R yet in CA?

also here in SoCal but newer 5th Gens shouldnt worry about smog just yet. Its 6 yrs after the date of manufacturing... Mines a 2014 and wont have to worry about smog till 2020; thats when the warranty for the factory cats expire.
 
also here in SoCal but newer 5th Gens shouldnt worry about smog just yet. Its 6 yrs after the date of manufacturing... Mines a 2014 and wont have to worry about smog till 2020; thats when the warranty for the factory cats expire.

yea that is true! But I'd rather not have to use o2 simulators and have the car run normally.... less wire splicing etc etc...

Does anyone know if the bullydog works with the 2015's? A buddy of mine has his on his Xterra (i know its a different platform).

Also what headers fit the 2014 / 2015?? Trying to find a link...
 
yea that is true! But I'd rather not have to use o2 simulators and have the car run normally.... less wire splicing etc etc...

Does anyone know if the bullydog works with the 2015's? A buddy of mine has his on his Xterra (i know its a different platform).

Also what headers fit the 2014 / 2015?? Trying to find a link...

Check out urdusa.com. Waiting for the spec u headers but I am tempted to pick up a set of jba 304 stainless... Tubing, flanges, everything is 304 stainless on the jba's for a very reasonable price.
 
yea that is true! But I'd rather not have to use o2 simulators and have the car run normally.... less wire splicing etc etc...

Does anyone know if the bullydog works with the 2015's? A buddy of mine has his on his Xterra (i know its a different platform).

Also what headers fit the 2014 / 2015?? Trying to find a link...

nope no such piggy back ecu will work on a toyota ecu ... it works as a fancy gauge
 
Bringing this back to life, anybody heard about/ used these?

THY-518-LS-C Thorley Header, 2013+ FJ Cruiser, 4Runner V6 w/air

304 Stainless long tubes.. buddy had Doug Thorley shorties on his FJ a few years back and was not impressed.. hoping someone has better news with these.

Don't want to keep peeking back at that supercharger thread :peep:

edit: oh and for you early headers adopters here, care to share an update on how its been?
 
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I just purchased a set of DT Headers for my 2018 4R OFP and am trying to make sure I understand everything I need to do to SAFELY install them with no long term problems. I got the long tube headers from Doug Thorley, and per their instructions bought a URD O2 Simulator. I planned on bringing those pieces of hardware to a professional performance shop to install. I got specific instructions from the Sales Manager from Doug Thorley but I am trying to get a good gauge to know if there is anything I missed. If I install the headers, with an O2 SIM is that all I need for it to be safely installed for the long run? I had heard from a local shop (which contradicts Doug Thorley directions) that an O2 sim isn't sufficient for the long term and I need to get it tuned. Does anyone have some thoughts on all of this and give some advice as to how I should proceed?
 
I just purchased a set of DT Headers for my 2018 4R OFP and am trying to make sure I understand everything I need to do to SAFELY install them with no long term problems. I got the long tube headers from Doug Thorley, and per their instructions bought a URD O2 Simulator. I planned on bringing those pieces of hardware to a professional performance shop to install. I got specific instructions from the Sales Manager from Doug Thorley but I am trying to get a good gauge to know if there is anything I missed. If I install the headers, with an O2 SIM is that all I need for it to be safely installed for the long run? I had heard from a local shop (which contradicts Doug Thorley directions) that an O2 sim isn't sufficient for the long term and I need to get it tuned. Does anyone have some thoughts on all of this and give some advice as to how I should proceed?

A pre cat O2 sim is a really bad idea. The ECU uses the data from the pre cat O2’s to determine fuel mixture. Likely no amount of tuning is going to matter as the air/fuel mixture is constanly monitored and adjusted. Until our ECU’s can be decoded and a proper tuning controller can be used I would not use these at all.
 
I had heard from a local shop (which contradicts Doug Thorley directions) that an O2 sim isn't sufficient for the long term and I need to get it tuned. Does anyone have some thoughts on all of this and give some advice as to how I should proceed?

The Toyota ECU's are effectively locked and can't really be tuned like most other vehicles. I think I heard Magnuson was reprogramming some ECU's at their facility for their superchargers. Aside from that the only other thing that comes to mind is URD's UCON-EMS box, which Gadget says will eliminate the need for an O2 Sim and allow for self tuning. It's what he shipped out with the URD/Whipple supercharger. I had the shop install the URD Spec-U Equal Length LT headers when they did the SC install. I did have the CEL come on for catalytic converter issues about 2 days after I got it back. I cleared it and am waiting to see if it returns (been a week).
 
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Orange Tuning was able to crack the 3rd gen tacoma ECU, I'm guessing they can do ours as well. I traded my taco in for this 4 runner so I dont visit the forum any longer but they said the gains were not much, unless you opened up the exhaust. The big deal for those engines was akinson issues, which we don't have. If I remember correctly they said the gains were mainly driveablity was enhanced everywhere including low end which the 3rd gen has none.
 
Do you remember what codes u had?

I don't recall, it was late when I did it. When I saw catalytic converter I dumped them, because they were removed with the headers. I did add a cat to the mid-pipe, but it's well downstream of all the O2 sensors. If they come back I'll post them back up, and let you all know what Gadget says.
 
Thanks for the quick responses and I appreciate the information. I will most likely wait to get them installed until more is developed and there is tuning available for the 2018's. DT suggested URD or Magnum Tuners for an O2 Sim and just to be clear, the sim was downstream of the headers. I'm getting too many mixed reviews and suggestions from manufacturers, people, forums, shops and all the other places I've asked for advice from. I thought it was simple enough as DT outlined to install the headers (deleting the 2 upstream cats) and put in an O2 Sim with the O2 Sensor and call it a day. I've heard that this solution isn't enough and you will ultimately need to tune the vehicle, and that these are not able to be tuned yet, etc. I cannot get a resounding answer that this will work for sure and not cause me to have any issues down the line. I got these for an amazing deal from DT just to put them on the truck so they could say they work 100% on an 18, which is what gave me the incentive to buy them in the first place. I suppose they will sit in the box until I can sort this whole thing out =(
 
Orange Tuning was able to crack the 3rd gen tacoma ECU, I'm guessing they can do ours as well. I traded my taco in for this 4 runner so I dont visit the forum any longer but they said the gains were not much, unless you opened up the exhaust. The big deal for those engines was akinson issues, which we don't have. If I remember correctly they said the gains were mainly driveablity was enhanced everywhere including low end which the 3rd gen has none.

I've been talking to Mat over at OVT, and he is going to start work on our 5th gen 4runners. He said when he get's things caught up, he would send me a handheld. We will see where this goes.
 
Thanks for the quick responses and I appreciate the information. I will most likely wait to get them installed until more is developed and there is tuning available for the 2018's. DT suggested URD or Magnum Tuners for an O2 Sim and just to be clear, the sim was downstream of the headers. I'm getting too many mixed reviews and suggestions from manufacturers, people, forums, shops and all the other places I've asked for advice from. I thought it was simple enough as DT outlined to install the headers (deleting the 2 upstream cats) and put in an O2 Sim with the O2 Sensor and call it a day. I've heard that this solution isn't enough and you will ultimately need to tune the vehicle, and that these are not able to be tuned yet, etc. I cannot get a resounding answer that this will work for sure and not cause me to have any issues down the line. I got these for an amazing deal from DT just to put them on the truck so they could say they work 100% on an 18, which is what gave me the incentive to buy them in the first place. I suppose they will sit in the box until I can sort this whole thing out =(

Meh, partially true. If you throw on the headers and install the 02 sims, everything will work just fine and you'll see some gains, and you certainly won't hurt anything. To get the FULL potential out of the install, yes you would need a proper tune. But still, the vehicle's computer will adjust a bit, and again, you'll see an improvement whether you tune it or not. No need to keep them sitting around, send it my way if you don't want it!
 
Do you remember what codes u had?

Code came back this morning while driving to work:
P0420 Bank 1 Catalytic Converter Inefficiency

The first time there were 4 codes, but I had been driving it harder right after the SC was installed and was still having issues with the catch can as well. I emailed Gadget, but probably won't hear back until Monday afternoon. In the mean time I erased the code and kept on trucking.
I'm hoping that Gadget can provide an updated file for the UCON-EMS that will tell it to ignore the catalytic converter codes. Although I'm starting to think that without cats between the sensors, I might have to replace those rear sensors more often than OEM spec.
 
Code came back this morning while driving to work:
P0420 Bank 1 Catalytic Converter Inefficiency

The first time there were 4 codes, but I had been driving it harder right after the SC was installed and was still having issues with the catch can as well. I emailed Gadget, but probably won't hear back until Monday afternoon. In the mean time I erased the code and kept on trucking.
I'm hoping that Gadget can provide an updated file for the UCON-EMS that will tell it to ignore the catalytic converter codes. Although I'm starting to think that without cats between the sensors, I might have to replace those rear sensors more often than OEM spec.

Yep thats your secondary (post cat) o2 sensor code. Wont affect drivability at all. Main problem now will be you wont know when other codes pop up.
 
Yep thats your secondary (post cat) o2 sensor code. Wont affect drivability at all. Main problem now will be you wont know when other codes pop up.

I'm not a fan of a Christmas tree for a dashboard. So I grabbed my cheapest OBD2 reader/eraser and threw it in the center console, now I can clear codes at will. Cleared that code while I was filling the tank this morning. Hoping Gadget has a more permanent solution.
 
I'm not a fan of a Christmas tree for a dashboard. So I grabbed my cheapest OBD2 reader/eraser and threw it in the center console, now I can clear codes at will. Cleared that code while I was filling the tank this morning. Hoping Gadget has a more permanent solution.

I'm sorry if this is sounds uninformed, there are parts to this code process that are new to me. If I get a scanner/eraser and I drop in the headers and sims and the code comes up I can just erase it? If I continue to erase it should it arise then the engine will run just fine and it will just become a problem if I leave the check engine (from the tripped code) on? Im looking at the following scanner:

Lemur Vehicle Monitors
BlueDriver Bluetooth Professional OBDII Scan Tool for iPhone, iPad & Android (for wireless connection with my phone)

ANCEL AD310 Classic Enhanced Universal OBD II Scanner Car Engine Fault Code Reader CAN Diagnostic Scan Tool - Black (if I wanna go simple I suppose)

When I get one of these and a code comes up I just plug it in real quick and erase the code to set everything back to normal? Thanks for all the help in this issue, I like to try to understand what Im doing before I go ahead and do it.
 
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