The Build Thread of my Rocky !!!

very very disappointed with this dyno run ...

return of power was 4hp & 1ft lb of torque.

I might re do another dyno run after doing an oil change in a week or two... Just to verify the dyno reading...

but I'm very very disappointed with the hp to dollar ratio...


maybe if I can borrow a set of stockies to dyno with ... would be awesome

Seems about right to me for exhaust mods, unless you're going to long tube headers and even then on a 4.0L I'm not sure I would expect much. Where to told that it would provide a certain increase? The ground clearance seems to be the bigger benefit. My experience with intake and exhaust mods has always been a bigger improvement on the but dyno since it sounds like much more aggressive (with the exception of my turbocharged car).
 
First of All I must apologize for the people following my thread. I did you guys an injustice by jumping to conclusions on the y pipe without reviewing the data. I sincerely apologize.

But after further review of the data sheet. I didnt make peak power but the power & torque under the curve gained alot more ... As much as 26.6whp & 43.4 ft lb of torque

please review on your own :
23826586801_4ea4c81bc7_b.jpg



for those too lazy... I did the math and will show you the gains:

23827117611_c8596deaf9_b.jpg
 
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First of All I must apologize for the people following my thread. I did you guys an injustice by jumping to conclusions on the y pipe without reviewing the data. I sincerely apologize.

But after further review of the data sheet. I didnt make peak power but the power & torque under the curve gained alot more ... As much as 26.6whp & 43.4 ft lb of torque

please review on your own :
23826586801_4ea4c81bc7_b.jpg



for those too lazy... I did the math and will show you the gains:

23827117611_c8596deaf9_b.jpg


To be fair you truncated off 2900 and 3000 rpm showing significant losses. I don't think you have a great comparison until maybe 4000 rpm and then you have an extra ~3% which isn't bad.
 
To be fair you truncated off 2900 and 3000 rpm showing significant losses. I don't think you have a great comparison until maybe 4000 rpm and then you have an extra ~3% which isn't bad.

We cant replicate dyno runs under 3000rpm due to traction control stepping in below that and we had to roll into the power instead of going WOT right away. So both test are done the same way ( actually all of them are). And because of that any data you see below 3000rpm isn't legible...

So the loss you see isn't right.
 
Kind of surprised the gains were not more up top. I would give it another pull or two. The gains down low are almost too much. It points to something being off a bit maybe.

I did it for the clearance, but the gains surprised me and I'm pretty sure I have a very accurate butt dyno LOL. Maybe it is just more tq down low though since it was already pretty good up top.

It does not really matter... It's no race truck either way. It does feel much better. Plus, the clearance is the main benefit.

Thanks for doing the dyno though... It's cool to get that info. Most people don't even know how to read one and just focus on the peak numbers....
 
Amazing

Such an AMAZING build, this is exactly how I envisioned my own 4runner. I have a 2015 SR5 in Nautical Blue. Unfortunately mods will wait until I no longer have 3 car seats in the 2nd row!
 
We cant replicate dyno runs under 3000rpm due to traction control stepping in below that and we had to roll into the power instead of going WOT right away. So both test are done the same way ( actually all of them are). And because of that any data you see below 3000rpm isn't legible...

So the loss you see isn't right.

If you hold the traction control button down for several seconds while you are stopped, my understanding is that it will turn off the traction control completely and not let it come back on when you reach a certain speed. [MENTION=118444]flyinhawaiian01[/MENTION] can confirm if I am wrong.
 
If you hold the traction control button down for several seconds while you are stopped, my understanding is that it will turn off the traction control completely and not let it come back on when you reach a certain speed. [MENTION=118444]flyinhawaiian01[/MENTION] can confirm if I am wrong.
yes. while completely stopped, with engine running, hold down the TRAC button in overhead console for ~3 secs and it will disable both TRAC and VSC. yellow lights on the instrument panel will confirm both systems are off, and they will remain OFF until you turn off the ignition.
 
yes. while completely stopped, with engine running, hold down the TRAC button in overhead console for ~3 secs and it will disable both TRAC and VSC. yellow lights on the instrument panel will confirm both systems are off, and they will remain OFF until you turn off the ignition.

I've known this because this is the same procedure for my FRS. There's an actual track mode frs but thas totally different than just holding traction control for 5 seconds.

But something happens on the dyno. The rollers does something and traction control kicks on or it would shift down... I've seen this happened each and every time on the dyno with my 4runner.
 
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I've known this because this is the same procedure for my FRS. There's an actual track mode frs but thas totally different than just holding traction control for 5 seconds.

But something happens on the dyno. The rollers does something and traction control kicks on or it would shift down... I've seen this happened each and every time on the dyno with my 4runner.

I wonder what reaction either disconnecting the front wheel speed sensors may have, or a jumper at the OBD port similar to zero point cal (g sensors). I truly have no clue but you're not the only one to experience the same dilemma.
 
[MENTION=116156]TheWraith[/MENTION] I installed the y-pipe last night and only then realized that there is nothing to fill the second O2 sensor bung on the passenger side of the pipe. Am I missing something, or did you just pick up a plug for it? My 4R sounds pretty rinky dink right now so I'm definitely going to try to find a fix today.

Any help is greatly appreciated!
 
[MENTION=116156]TheWraith[/MENTION] I installed the y-pipe last night and only then realized that there is nothing to fill the second O2 sensor bung on the passenger side of the pipe. Am I missing something, or did you just pick up a plug for it? My 4R sounds pretty rinky dink right now so I'm definitely going to try to find a fix today.

Any help is greatly appreciated!
[MENTION=120994]SalsaRed[/MENTION]
It should have came with 2 bolts and gaskets to fill the 3rd hole... look in the box
 
[MENTION=120994]SalsaRed[/MENTION]
It should have came with 2 bolts and gaskets to fill the 3rd hole... look in the box

Yea, there should be a plug for the extra sensor bung. It's there for people to run a dedicated wide band if desired. Would be real useful if there was ever a way to tune these motors.
 
Thanks! I went through my box and all of the packaging and found no plug. Luckily I found an oil fill plug that fit perfectly for now. I emailed URD about getting the proper one.

The sound is incredible with this and my Magnaflow 12256 muffler. The tone got surprisingly deeper and the gurgliness increased at low RPM's. At high RPMs the sound really comes out and definitely has more of a rasp to it now. The sound is pretty much the same at normal driving levels.

Power definitely increased and is exactly what I was looking for.

Unfortunately I sheared a stud on the header during the install. It's causing a barely audible leak, so I'll have to hunt down a replacement stud and drill it out.

Does anyone happen to know what size stud I need? I'm having trouble finding that info.
 
Thanks! I went through my box and all of the packaging and found no plug. Luckily I found an oil fill plug that fit perfectly for now. I emailed URD about getting the proper one.

The sound is incredible with this and my Magnaflow 12256 muffler. The tone got surprisingly deeper and the gurgliness increased at low RPM's. At high RPMs the sound really comes out and definitely has more of a rasp to it now. The sound is pretty much the same at normal driving levels.

Power definitely increased and is exactly what I was looking for.

Unfortunately I sheared a stud on the header during the install. It's causing a barely audible leak, so I'll have to hunt down a replacement stud and drill it out.

Does anyone happen to know what size stud I need? I'm having trouble finding that info.

Do you mean one of the studs on the primary cat flange? The are threaded.... So you should be able to twist it out from the other side after removing the entire things from the vehicle.


When installing the Y pipe I had to drill out one of the flange holes slightly bigger to get it to slip onto the stud without causing damage.
 
Yep those are the ones! I'll have to give that a try tomorrow if I have time.

I probably should have drilled out one of the holes on mine too, it was pretty tight on the other side. Luckily I caused minimal damage to the threads on that one and was able to get the nut on with no problem.
 
[MENTION=116156]TheWraith[/MENTION] Hey man when are you going to dome some more performance mods and dyno them? Maybe some shorty headers (since you're in CA) or the URD MAF calibrator. Many posts of people buying the MAF calibrator, but not a single one has reported back with results.
 

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