Heres an interesting idea. It was asked by a friend and I didnt have an answer..

Go from the headers to a Dr. Gas 3" X pipe ( http://www.drgas.com/item.asp?id=23 ) and then to a Flowmaster merge colector (3.5 or 4" outlet) and then run it over the axle to a good flowing muffler (Hooker or Magnaflow) and then out. Youll have the gains of the X pipe without all the clearence or drone issues....

 

hmm what i understand is that you want to to a y pipe behind the x? i think u might as well go with a y-pipe 3.5" or 4" setup and just not use the x-pipe. i my self use a 3" true daul w/ x-pipe setup on my 68 conversion.

Kyle

 

i believe the primary reason why you get gains from x-pipes are because they equalize flow, with adding a y-pipe at the end that's just countering the effect....plus length issues...

 

An x-pipe is an improvement on a dual exhaust system. You'll find it does very little on a y-pipe setup.

 

I thought this had been discussed one or twice? running the x pipe and the flowmaster merge collector right after it......it negates the effect of scavaging exhaust b/c of the bottleneck(even tho 4" isn't much of one, still). however, since you are still using the x-pipe so close to the headers, it may work better than the other guy who wanted to run the x-pipe after the axle

you might want to call lane up, he'll probably have some thoughts on this.

 

Thats what I was thinking. Youll still get the scaaging effect of the X since its still close to the headers which is what makes the TQ. Anything after that is just a way for the exhaust to get out. Whats the bottle neck? A single 3.5 will flow as much as a dual 2.5" pipe. It was just an idea.

 

It's not just the overall flow. When you have *true* duals ( no x or h pipe ) you loose some scavenging because there are less cylinders pulsing per pipe. If you ultimately connect the two pipes into one after the x-pipe you have only created a more complicated/expensive stock style single exhaust.

 

Agreed

Kyle

 

So basically putting the y-merge in there, no matter the flow, will negate the scavanging effects of the x-pipe pipe? Thats how I see it?

 

X-pipe + Y-pipe = Useless

 

Yes. Another way to think of it is...an x-pipe doesn't build tq, it puts tq back into a true dual exhaust system that lost tq in the first place.

 

I understand the torque deal. I was just makin sure that I was correct on the y-merge negating the x's gains.

 

for the record, a true dual system will sit no lower than a 3" y pipe

the driver side pipe behind the header is the low spot ... if you use bullets the section of pipe behind the x or h can be twisted so that the bullets point slightly upward so that the bottom of the sits even with the rest of the system

 

Although I agree, that true duals can have the same clearance, many would not. Many people do not do what it takes to achieve that clearance, unfortunately. Since you made your own system, you had a slight advantage

 

It never made sense to me that GM didn't make room for duals when they designed the 4th gen. It's not like it would have been that hard. If/when the 5th gen comes out I'll be surprised if it has duals.

 

I think the best way to do it would be to make the ypipe equal lengths. According to the website, an equal length ypipe works as well as the xpipe. It would be easier to do than a combined xpipe, ypipe. An equal length ypipe might cure the rasp problems as well. Mac headers primaries are unequal length and are very raspy. This makes me think the rasp is caused by unequal length piping.

 

i don't see much of a way around unequal y-pipes with the current clearance and space issues. ????