This is going to be a long post so I will apologize now......SORRY!
Ok, now that's out of the way let's get down to my issue. Initially my exhaust setup was a set of Hooker Competition Long tubes 2210 with a modified Mufflex dual 3 in to 4 in y pipe and a Mufflex 4 in exhaust. Everything fit up nice and tight with the 5 speed in the car. Since then I have switched over to a built 700R4. I had to ditch the long tubes and mufflex y pipe, and ended up running a set of Dyno Don's 1 3/4 shorties and matching y pipe. The exhaust fits good as well, following the factory exhaust routing. My passenger front tire hits the exhaust tube when I go near full lock because I have 275/40/17's up front on a 9.5 in wide rim. The overall exhaust note of the car has changed though, and I don't like how raspy it sounds. So far, I have tried searching and could not find any conclusive information about if there are any true long tube headers specifically designed for the 82-92 f body that will fit with an automatic and give any REASONABLE ground clearance. This car is a daily driver/street/strip car. I do have other problems however such as these...

1. The car is lowered with a pro kit as well as the Spohn tubular adjustable front lower control arms with spring boxes that from what I gather also lower the car another 1/2 inch.

2. I have the Spohn tubular adjustable torque arm and transmission crossmember that as other TGO members have posted, can be a pain to work around, especially since the crossmember has these side gussets that hang down lower than the factory transmission crossmember.

3. The Spohn torque arm does not have a fixed mounting location as it attaches via a swinging arm bracket deal. Basically, no exhaust pipes can be routed on the drivers side at all without clearance issues, they won't fit in the tunnel next to the trans, and they cant go under the trans x member. Pretty much everyone here already knows this.



Some of the pros that I have going for me are...

1. I have the Spohn tubular K member. I have tons of room around the oil pan area and just tons of room in general.

2. I have the BMR panhard relocation bar for extra exhaust clearance when it goes up and over the axle.

I have thought about using squared or oval tubing, but I am not sure how well that stuff flows and I can imagine it might be more difficult to work with. So far I am coming up with nothing but compromises. I want long tube headers with 1 3/4 primaries and 3 inch collectors. I want a dual 3 in inlet to 4 in outlet y pipe, and I want to retain all of my ground clearance so I don't hit the exhaust off every pebble I come across while driving down the highway. Someone please tell me that there is an answer for me! I have been looking at the big block header that Hooker sells for our chassis (the 2226-1) and I wonder if they could use that same template but make it sbc style. Or have I completely gone out of the realm of off the shelf parts and will need to just sack it up and get the headers and y pipe custom made? Thanks for any insight on this.

 

I currently have Dougs long tubes and they scrape over everything taller than a painted crosswalk stripe. I went with 2.5" off the headers, and they were still very difficult to get around the transmission tunnel "subframe" and over the trans crossmember with the 700R4, I had to "ovalize" (Smash) the tubing going over the crossmember, so the area is somewhat compromised not far off the collectors.

Unless you are willing to hack and completely re-design the lower part of your car, or make custom long-tubes that went forward for a while before they came backward, I can't imagine how you will be able to do what you want to do. Our cars were never designed to have exhaust plumbing routed through the transmission hump area, so there is no room. There were some long-tubes made years ago that snaked through the stock exhaust route, but they were 1.5" and quite expensive, so they didn't sell well.

If you don't like the sound, try some different mufflers?

Good luck

TA

 

Well, I think that my only saving grace is the fact that I have the tubular engine crossmember that gives me extra room to work with. I am figuring that I will probably have to make my own headers at this point. I tried to visualize how they would look in my head. On the driver's side header, the primaries will come down and back like a normal header, but only about 5 or 6 inches or so before each primary gets bent back towards the front of the car. The collector will end up facing towards the front of the car, and the pipe that connects to the collector will be 3 inch and travel just in front of the oil pan where the sumped section is. The pipe will continue along the factory routing to the passenger side and come out just behind but outside the transmisson subframe.
The passenger side header will be a normal long tube header. I am thinking about square notching a section of the transmission subframe a couple of inches back from where the collector ends and routing another 3 inch pipe through that section.
In the end, both pipes will be 3 in, they will both be located on the passenger side under the floorpan, and being able to utilize my dual 3in into 4in y pipe, will hook right back up to the rest of my exhaust.

 

Your new exhaust is raspy because of the stock-type design of the y-pipe. That design doesn't promote efficient or equal gas flow from each header. The exhaust pulses "collide" with each other so to speak causing turbulence disrupting the velocity flow which is where your rasping comes from... Hawks makes a very high quality set of 1 3/4" long tubes with, from what i can see, a much better y-pipe design (not too many people have these so its hard to get feedback. see below for why). It seems as though they are definitely worth looking into.

Pros:
1 3/4" primaries
y-pipe has 3" collector
stainless construction (headers and the y-pipe)
excellent ground clearance

Cons:
extremely expensive ($1100 for a set)
did i mention they were expensive?

 

That hawks y-pipe wont fit around that Spohn monstrosity of a crossmember anyway. Anyone else could make that y-pipe and do the same thing with it.

This is an LS swap car, it's mw66nova's little brother (mw66nova made it), but it illustrates my point - you can't really run any kind of proper duals without cutting up the crossmember.







Now as far as the torque arm goes... Im not really familiar with that piece, so you may not be able to run it down the tunnel at all anyway, so that may not be much use to you.

 

i have long tubes and true duels ( strait piped atm) with 3" pipes and i never rub the pipes ill post some pics how i ran mine this weeking if i can figure out how to post them my lowest point is where the trans cross member is ill take a tape to it and see how far off the ground it is the only time i ever hit is if i go like 20mph over a speed bump

 

not as clean as your set up and the driverside has a hanger broke in this pic (its a old pic)

 

If you dont mind a lil cutting and welding on the subframe and trans xmember you can do this.
Eventually it will b a stainless 3" Ypipe into a 4" cat back thru a muffler with 3" pipes just like the TOTL


Dont look at the crappy welds. Its just a pattern exhaust and I ran out of gas 4 the welder and had to drive it home.


I pie cut the factory trans xmember on both sides so it hangs down in the center. Instead of the other way around.

 

Hooker p/n 2138 is a set of longtube headers that are designed to follow the factory exhaust routing. Primary size is a little small at 1.5" diameter. Last time I checked they still offered them and there was an article in PHR or Car Craft years ago where GM Performance did an LT1 swap on the prototype 25th anniversary Camaro and used these headers.