OK....personal truck time.....I have been batting this around in my head for the last few weeks.....

I want stacks....i will have stacks...and i am going to build my own set-up. I have all the stuff (OR access to it) needed to do it. What i want to know is this:

Should do the split for the stacks with 4" pipe (Y-Pipe) or just do a 2"x4" (I think this is as good as 4” pipe volume wise??? Yes?) square tubing manifold with the stacks welded to that? I can make it so the smoke is distributed equally no prob either way...

Is the square tubing rout going to be too restrictive (Going from round to square then back to round again....not good for flow).........or just look at it in the sence that stacks don’t flow very well anyway and just do it. (Lots of 90* Bends in the stack setup.) I think my losses would be very marginal...and i think that i can cover up the square tubing easier than the round pipe.....i don’t know...what are your thoughts? I have seen this done very cleanly…..but....i missed out on my class on Thermodynamics....so any with better knowledge chime in please!

If the gains of going to round pipe over square tubing is very marginal, I think I will do the square tubing………for ease of building……

 

I've built both, and the square/rectangular tubing is much easier to build, and I saw no difference in spool-up or EGT's

 

I don't think it'd be a big problem. I'd personally do a 4"x4" square tube instead of a 2"x4". Just to try and keep everything the same size. Also, are you doing 5" stacks or 4"? 4" is going to be to small and dorky looking. And don't worry about the smoke coming out equally, you don't have any anyways.

 

I have SOME!!! I do have 105 HP sticks in there! I was going to run 2" stacks........thought that would be unique ........what the heck do you think i am going to run! 5"! I dont know...but i think 4x4 would be too big.......cool off the flow too much.......

 

It can't be that big of a deal on cooling off. I'm running a 5" y-pipe to 5" stacks and it hasn't affected spoolup or EGT's. Dan, my truck puts out more smoke when I fire it up than yours has ever dreamed of.

 

2"x4" square tubing provides 8 square inches of cross sectional area while 4" round tubing provides 12.57 square inches of cross sectional area. Hydraulically speaking, that's a significant difference but since you'll be splitting the flow I couldn't see it being a big issue.... you'll be taking the full flow through the 4" (pre-split) and then you'd be taking around half the flow through the each side past the split. The 2"x4" is probably sufficient for that as long as you keep the flow on each side of the split to around 50% of the maximum flow. Anytime you abruptly change the cross section(4" round dead headed into 2"x4" square tube) you introduce expansion/contraction losses in your flow regime. Of course, it's probably not nearly as big of an issue when dealing with gases as it is with liquids.....

Thermodynamics probably wouldn't have helped as much as fluid mechanics....

 

Yeah....missed that class too.......

Blue.......

OK...i feel better......im just going a differant rout.......i useing caps too! haha.......*DING, DING, DING*

 

I'd be better off had I missed that class... I didn't learn much if anything from my teacher who couldn't speak english as I have since working as a bridge engineer and actually doing open channel modeling.

 

I used 3x6... the 5" pipe sat perfect on it

 

im going with forrest. i used 4x6 and the 5" pipe fit nice and square on it. you'd be dealing with a reducer if you went with a 2x4 or a 4x4.

 

I got a 4" to 5" reducer......didnt think that would hurt since the rest of the exhaust is going to be 4" anyway......

 

true. if you already have the reducer, it should be easy.

 

WELP...i guess i will go with the Tubing.......any suggestion on gauge....i thought about 1/4"...and then hit it with some BBQ Paint. Then get some Diamond plate broken to cover up the manifold, and to act as an heat sheild....i do have a drop in bed liner........huh....never gave that much thought.........

 

1/4"? Are you kidding me? Mine's like 1/16". The BBQ paint is a nice idea. It would help hide all of the burnt on stuff that my "friends" have put on. Mine haven't hurt my spray in liner.

 

My only issue with a lighter gauge metal....is that the flow is going to have "Hot Spots" with the Square tubeing....i can lessen these with some angle iron and such...but...still...i dont want to have any burn through......