Does anyone have experience with purchasing and installing the 5Star Y-pipe? I am kicking the idea around but am wondering as to actual gains from removing the stock choker besides the "flutter". Also, what is the flutter and on a scale of 1-10 how annoying/unnerving is it?

 

OMG YES!!! This is the best mod I ever did to my 6.8 besides the SCT tuner. 5star tuning has a combo deal and it is amazing. Please please please get them together, it wakes the truck up and is like a new vehicle!

 

That's good to know. I hadn't seen a package deal, but I did notice that because I'm in the nanny state of CA that they won't ship me a tuner....
I'll check the website for the package and if I can't find a solution at least pick up the Y-pipe.

 

Charles, what year is your EX? Which factory Y pipe does it have? The early Ram's Horn design really wasn't that bad but the later necked down T shaped abomination is a real gem. (That NEEDS to be changed out for a full flow Y pipe!)
The reports of exhaust flutter following the upgrade from the T pipe to a full flow Y pipe are very rare. I run the Banks headers with full flow Y pipe and have never heard any flutter, I also run a selection of 5Star's custom tunes and I agree they do provide a very nice improvement.

 

 

I'm not a fan of exhaust upgrades but have to say from reading the responses that I'm almost convencened.

If you all could be a little more specific on what exactly this exhaust upgrade does I would appreciate it.

If I could get another 30 to 50 hp on my supercharged V10 due to a exhaust upgrade that would be really good.

 

Use a parcel forwarding service like "Shipit.to" or "Stackry". They have warehouses dotted around the country - you ship it to your choice of them, then they forward it to you (even internationally!)

 

 

 

I run a 12 psi pulley but rarely see over 7 or 8 psi because I'm under 3000 rpm 99% of the time. I have hit 10 plus psi during light towing but don't like towing with a supercharger.

The only other time I've hit 12 psi is during the tuning phase of installation at WOT.

I have seen the non ram horn wye pipe as 1 of my 3 excursions have it. My supercharged V10 has a ram horn.

I am not a fliud and pressure dynamics expert so I cannot say what affect the orifice type restriction has on the flow of exhaust. I suspect velocity of exhaust is key. This " restriction" may increase velocity of exhaust which can be important.

That's why I asked for more details. I do know the number of bends affects friction and the ram horn has 180 degree bends. A orifice may alow vacuum to pull exhaust out more efficient. .......I just don't know.

This motor is made for torque, and torque is peaked at about 3200 rpm.

So, I will ask this:
What affect does a modified wye pipe have on torque at 3200 rpm. Does it move peak torque to 3400 rpm? Or maybe 3000 rpm?

Does peak torque increase or maybe decrease and peak torque rpm stays the same?

My orifice type wye pipe shows no sigh of excessive black carbon buildup.

Ideally the manufacturer would provide a graph of hp and tq graphs so we can determine the benifit of the new wye pipe. I rarely see those for exhaust mods, I don't know why. But it makes me suspicious.

 

I have an 2003 6.8L stocker. I have slid under and noticed that I do have the chunky necked down version. Is the Y-pipe a straight weld in or will I need additional fab work?
As far as shipping, I am planning an out of state visit to a family member's place in about 6 weeks...not sure if I want to wait that long though...

 

 

Wow, I just went to 5Star website.

They claim 33hp and 35 ft lbs torque increase with their wye pipe.

They have 2 kinds, 1 for the ram horn and one for the orifice kind. Both claim 33hp and 35 ft lbs.

That is a total of 343 hp and 460 ft lbs. That's pushing injector and fuel pump limits, but within range.

That's alot of hp and TQ for a $100 mod. Basically claiming 10% on hp and 8% on TQ.

For me that's 50 hp and 60 ft lbs.

I guess I will waste $100 to see.

 

I am in the same boat. Before I started visiting here I had no idea about 5Star. I guess when we do the family vaca out of state with the X she will be carrying some new parts home

 

I put the 5 star in mine. It's a little tricky to weld it in, kind of tight quarters and awkward angles, but it can be done. I did notice improvement in performance, and I also notice the flutter. It doesn't bother me, but it is there at certain rpm.