Hunterdon County

 

Ok, I got some pics.

Who can I email here that could post them?

I am trying to learn, but right now it would be a great help if someone could just post them for me.

Thanks

 

damn it looks as if the pipes like pinch together...I mean if i just made it a true dual would that be good enough? lol cause if i do 2 inch pipes coming off the cat and just have themcome straight back and weld a big pipearound both and then just have it come down to fit the muffler i have now! would that work and solve the problem?

 

thats correct, where the two pipes come together is were the restriction is. by removing that section and putting a bigger y in you will gain power. if you want go straight duals back by removing the y completely, but you will need to put an x-pipe into help balance the exhaust. i just went with a larger piece were the two pipes connect. i have the 3 inch single catback which is good enough. by going larger y-pipe or true duals with headers you may lose some low end torque. keep it small 2 or 2 1/4 and you may be alright

 

So no one wants the pics of the stock y-pipe? It is all cut off and maybe 6" long.

This way you can see inside the thing very clearly and see how it is NOT a restriction. It is the f'n pipe size I tell ya. [sm=exactly.gif]

When someone ask me on another board for proof, I went and got it. Now no one wants to believe it. Hell I have offered to show people in person, yet no one takes me up on it?

 

how are u going to prove it, is the question, if superdak says he felt alot of gains when he put the new one in, then it was restrictive.........

 

First off, I am not saying the man did not feel it. I don't know his situation, so I can not comment on it.

What I can comment on is the testing I did, with help of my boss.

I work 2 jobs, one is as an engine assembler of race engines. We do drag engines only. With his help, we welded in bungs in many locations is the stock system.

Test were done on my 05 4.7 V8 w/less than 20k on the odo.

In each bung, we would take pressure measurements. This was down to a .10 of a PSI.

A little off path here....

Auto mans. today give numbers and locations to check such things. These are used to check for clogs in cats. So my numbers and testing method is nothing new, and accepted by "the big guys" who build millions of cars a year.

Now back to my tests.

Starting from the front, no numbers, only an overview of the results.

Y-pipe: By this I mean as a whole. From cats to the joining of the 2 into one at the slip fit location.
Restrictive
Pipes from cats are small, they measure out at 1.75" ID
Joined they measure 2.25" ID
Flow thru "Y" itself was good.
Flow thru each pipe as a unit of its own, too small for the engine.
Cut off "Y" and the numbers did not change more than a few .10 of a psi.


Will make another post so this one does not start acting up.

 

The stock mufflers, well not much to say except they do what they are intended to do, mufflel.

Any change in them will give positive results. Lets just say for now, don't buy into the whole "backpresure" thing. Simply, less is better...but it must be tuned for less. Or it may not help. Your cats provide enough backpressure to satisfy those who say they need it.

Change your mufflers, resonators, do as you wish. Just remember how they flow-

Baffles- ok. Some worse than stock
Louvers- better than baffles, but still restriction there.
Straight thru- no louvers, only perforations, best.

Stock pipes- SS but too small.

next post

 

What we found that works best, not including adding headers (another looong topic) is-

Cut off stock pipes as they exit cats.

Open up the exit to match the pipe size you wish to use. I used 2.5"

There right now is most of the "bad stuff" gone. So this leaves us at where do we go next?

Single or dual. Now when I say dual, I mean dual. None of this "true dual" ****. It either is dual, or not. Single into dual outlet is just that, dual outlet. So when I say dual, I mean dual pipe system, period.

So now we have 2 pipes from the cats, who want to start with a system from here? Dual? Single?

We can go on once someone tells me what they want. I will tell you what I have found from there.

 

look man i'm not gonna try to be a dick but i think you took that a little to far!! he was giving his best info on what he knows to be true. You know what SuperDak has done alot of motor work from what people have said and so that means he knows alot. not stating your wrong but dont' start calling people out and claiming your king of the rock over something that frankly isn't that important. granted you may be right you may be wrong...but what i'm gonna do is just simply leave it the way it is and get my headers put on and not mess with it. i figure it is good enough for me. I'm not going for massive power so it doesn't matter anywayyou know! so don't be burning bridges and making people look or try to make them look stupuid!! Just know that it's an opinion made by one of the other members and its just that an OPINION. so don't be making a big deal out of nothing man just keep it cool man!