OVT Dump Tube Thread

i am telling you man, the right exhaust on this NA motor is the second biggest thing you can do after OVT. go for it. most don't know the difference because they aren't willing to tear it all out and start fresh. any aftermarket catback or typical solution will not wake up this motor for certain, just some sound and a little throttle bump. but if you do it right the return is big.

round 3 is coming early next year. I'm about to tear it all out and do it again. these pics are round 2...



currently stock cats (after trying the catless tubes which leaked badly, then got the catted which ii haven't installed), URD mk2 Y pipe, reroute, two 3" Vibrants, a Spintech 3000XL and a J pipe. all of this will be replaced next year with custom tuned solutions. it's a massive performance improvement over stock, but I'm focused on inefficiency from the 3" mid and dual resonators, and i have a somewhat nasal sound, not bad just not my zone. sorry no sound clips atm.

 

I am not sure but will pay attention to idle. Also before changing the exhaust I would typically see about 10min of poor fuel economy at 12mpg and then a solid increase to 18 - 20mpg over the 20mile commute. Now I see sub 10mpg for ten minutes and the whole trip averages out to 15 - 17mpg.

I have never done logging before but would love to get it done and send you the data if you are willing to take a look at it. Can you point me to the procedure once its ready?

 

Yes, mine does idle higher for a bit longer. Was wondering why that was but makes sense now!

 

Guys I flashed the 2.0 4.88 decatted tune this morning and now get over 19mpg. Quick note, if you installed a full exhaust with rear cat delete and have catted dump tubes use the decatted tune! Dont be a fool like me and dont use the 1.05 tune with a full exhaust and end up with 13.5mpg

 

That U bracket is there to make it harder for people to steal your cats with a sawzall. It's not there to restrict movement of the exhaust during normal operation.

 

theres an order to things, and youre doing it backwards

 

You think its nasally that way? I am running the urd spec u with a really big MBRP resonator instead of and the muffler and one of those 3" vibrant super quiet reson lators and tbh its right about where I want it. Sounds a lot like a VQ to me. I suspect the length of my MBRP resonator has something to do with it, different shapes and sizes of resonator lead to different frequencies being cut out and I think the big one really helps with drone while the vibrant aided with drone but did the most for rasp

 

I’m thinking OV dump tubes, URD y-pipe, borla cat back, with possibly a vibrant resonator would sound great. Just my worthless opinion though.

 

i don't have rasp but i have 2 resonators. remove those and I'll have rasp. the resonators temper the nasal tone a lot, but they eat back pressure and make the system inefficient for open flow, although this is so far beyond stock. I'm getting this tuned Y pipe made and spec'd off the high flow cat tubes, so we're shooting to run 2.5" mid and no resonators at all. that should take care of the nasal, rasp, pressure loss, etc. hoping for solid gains in the middle with better sound and mileage. and expecting it.

 

I agree, with the URD Spec U it sounds a lot like a Nissan VQ -- I dig it. However, the drone with the spec-U was insane, and a Vibrant super quiet resonator didn't do much for it. You're happy with the MBRP resonator (26"? https://mbrpexhauststore.com/r1017-mbrp-resonator-3-inlet-outlet-22-body-26-overall-t304/) in place of the Magnaflow as far as drone goes?

Have you driven it on any long grades at highway speeds?

 

Just to let everyone know, we have had reports from 3 people that have issues with the dump tubes and URD Y pipe.
These issues only exist when using this combination, and using stock Y pipe there is no issue. (main issue is the exhaust won't seal)
So we will have our Y pipe ready soon that goes with our dump tubes.

I don't know why, I have no experience with the URD stuff.

 

equal length Y-Pipe?

 

I have a y pipe from DirtyDeeds and it comes with two midpipes which are separate from the y pipe so its not too hard to get it to lineup. But I do have a slight leak where the midpipe joins the stock dump tube and another leak at a weld joint on the y pipe. I bet the URD pipes may have similar issues. You can see in the pictures where the water starts dripping when i first start the truck.

 

Anybody running CATTED DUMP TUBES with everything else STOCK and pulling codes? I put my entire exhaust back to stock except the catted dump tubes and am still pulling PO420 and PO430 codes on stock tune, and catted dump tube 2.0 tune.

 

Still waiting for my catted dump tubes to ship... But will be installing them with stock y-pipes when they do get here so I can provide some feedback hopefully this year.

 

Try the decatted tune, I had codes with the catted tune, regular tune, 1.05 tune. Now with the decatted tune I get no codes and fuel economy is great. The catted dump tubes from OVTune are too high of a flow so it throws of the O2 sensor readings, something in the decatted tune as a secret sauce.

 

So why does he even have a CATTED tune if it still pulls codes...

he has said publicly that the catted tubes would not pull codes and that is just physically impossible. I think it’s comical that even with the catted tune he makes for those tubes, still pulls codes. Haha It’s pretty much false advertising. I would have just bought the catless tubes for less money and more power if I would have known ahead of time.

I understand the catless tune will keep it from pulling codes, but it’s frustrating cause that’s not what I paid for.

 

I think the only thing OVTune notes is that it didnt have any codes on his truck during testing but I dont know how many miles he drives. First time I got the CEL right away, then again after 700miles, and last time after 600miles. I now use the catless tune and havent had it come back but time will tell after a few weeks. I did go from 13.5mpg to 18mpg within 100miles so there has to be a significant difference between the catted and catless tunes. So far I got 400miles and its all good.

 

sigh... you've been frustrated with everything. Any answer we give you, anything we ask to check... your URD pipe with leaks... etc.
Send us the catted back I'll send you a decatted one and refund you back the difference if it's that big of a deal.

We made the catted option for people who have to have a cat. It's a high flow 200 cell cat. Look around at other exhaust manufacturers, they do similar things. It's still better than no catalyst at all as that is completely illegal for road use. Some trucks are popping up engine lights, some are not. It's hard to specifically "advertise" for the variations in this truck. That's exactly like the tune, we advertise what we see, test, and can confirm with our own truck. But then you have one person who loves it and one person who doesn't. Because the variance on these trucks are wide as hell.

For example, there are some trucks with non catted dump tubes that don't get a CEL on 1.05 or stock... and others that do. I cannot explain that variance either.


And It is surprising to see that exhausts from URD, Dirty Deeds, etc are leaking, have leak spots from a hole in the welds, etc. It's a little disheartening for people to try to blame our product when the welds, material and over-all quality its far and above what I have seen posted on here from other company exhausts.

 

I've graduated to 21.8 mph highway with the decatted dump tubes and the decatted 91 octane 4.88 tune (and running 285's with a little over 2" lift).
No CEL after 400+ miles.
Only one wish - that there could be a happy medium between the performance tip in acceleration most of us didn't like and the slightly sluggish acceleration of the 19800 tune. But that's nitpicking BS.

That said, I'm pretty damn pleased. Truck is the best it's ever been in this current configuration.