how difficult (or expensive) is it to get an exhaust shot to make me a y-pipe to fit my existing manifolds?

I live in a very strick area, even for visual inspections, and I don't want to risk the headache of haivng to lose my air pump, so I'd like to look into hogging out my manifolds and building a y pipe.

 

Are you reuseing the stock manifolds?? I went to a junk yard and found a amazingly great y pipe for my car. It was off a 2.8L and i have a 3.1L. I paid 15$ for it. The o.d. of the pipe actually seemed larger but worked out great.

 

I ported my 2.8 exhaust manifolds when swapping in my 3.4, and there's no "hogging" to it. They're a relatively good design, not much needs to be removed, and that's good since they're so thin.
It looks like the hot ticket is to just cut a stock Y-pipe just behind the merge, and do your porting in there before carefully welding the parts back together.

 

yes, I have an extra set of manifolds, so I could experiment with them. If they really don't need hogging out, and the main violation is the "t-pipe" then I'll look into having one made.

I'm gearing up for a 3.4 swap by next summer. I've got a line on a 3.4 with 50K original miles that I'm getting for free

 

do u have a welder?
if so just 1 mandrel ubend and a 2 into one merge and redo were its a t,and install the nice merge

 

Flowmaster sells a nice Y, but it may be a bit large for even a 3.4L.
Still worth looking at: http://www.summitracing.com/parts/FLO-Y200250/

 

http://www.mandrel-bends.com/catalog...mild-1657.html

http://www.mandrel-bends.com/catalog...steel-740.html

 

Project89's second link. Because 2.25" is too big for the manifolds to the merge. WAY TOO BIG!

 

good eye i clicked the wrong one

here is the nicer merge in 2inch inlets 2.5 out
http://www.mandrel-bends.com/catalog...-mild-945.html

 

still gonna be an easier fit than that one I found.

 

I really like that idea. so how does this work? I buy one of those pipes, and then ask a muffler shop to use it instead of the stock setup?

any idea what that will cost, and what the benefit will be? I've heard the the stock setup on these cars is a terrible design

 

it really is a bad design.

u could buy that merge pipe and ask the muffler shop to cut out the stock t piece and replace it with the merge, more then likley they will want to build a whole new y pipe. and the reason being is some of the stock v6 ex are dbl walled,basically a pipe inside a pipe.also weldig on old rusty ex pipe flat out sucks.

if u supply the new merge it shouldnt cost much.
what i would do is print out a picture of the merge u are goin to use and then go down to ur local ex place and talk with them and let them know what u want and see if they will do it and how much before u buy any parts

 

I'd print out both styles of 2->2.5" that p89 found, let them decide which would work best. I'd expect the shop to put the car up on a lift, then hold up the printouts to eyeball it, even if they already have some familiarity with V6 third gens.

 

There is some decent info in this thread:

http://www.thirdgen.org/techboard/v6...st-do-you.html

Both TomP and Ked85 (RIP) used some merge pieces in place of the T.

RBob.

 

That thread reminded me that I did a bit of grinding and polishing to the stock iron donuts that go between the manifolds and the stock Y-pipe.

 

I'm going to place money on that you'll want a new crossover pipe from Walker or one made by the shop... My factory 87 pipe, a replacement from around the same time, and the pipe I pulled from the 91 donor car all have the double wall piping. My original was broken in half just before the T joint and was a PITA to patch to drive just before I got the replacement pipe.

 

i never understood why they put double walled pipe on these cars, thats usually used on motor homes and large trucks.

and yes that double walled pipe sucks to repair or even weld in a new section of pipe

the only explanation i can think of was to keep heat in the pipes for the oxegen sensor

 

Yep... When I cut through the crappy weld job PO or whomever had done on my original pipe to realign it (I don't think the guy did ANYTHING straight!) and I saw that garbage, my first thought was "WTF?" .

Replacement Walker pipes, the last time I looked, were around $180... Probably closer to $200 or over now. I'll bet they're single wall, but, not having seen one, I don't know for sure. Probably better off having the shop make a decent one.

 

Also to light off the cat sooner to reduce cold-start emissions.