Well after buying a set of unkown headers I discovered they were only 1 1/2 primaries. I took em back and oerdered a set of hedman full length 1 5/8 prim 3' collectors and ceramic coated. Got them last night I'm going for true duals and h or x pipe I got stage 8 bolts and getting dead soft alluminum gaskets I will let every one how it turns out fitment etc...... wish me luck!

 

Man i'm having a hard time finding an exhuast shop that is willing to put true duals on my car! They either say it can't be done or it's illegal to modify 81 and newer emmissions! AAARRRRGGG!

 

the only thing thats fun about true duals is the sound they make
single 3 inch would be better for ur car unless ur making over 350 hp or so! u will save more money with a single 3 inch and make more power cause u will have more back pressure!
jesse

 

The sound is exactly what I want
I don't plan on making more than 350 hp

 

Most exhaust shops won't run duals since it is illegal. What you can do is talk to one of the guys at the shop and have him do it on the side for cash. That's the easiest way around that. Keep us posted on how it goes.

 

Well I think I found a shop it's a long drive, (middle of Kansas) and i'm in the Kansas City area. But I will get this done!

I'm gonna go for the largest size pipe I get get that don't ruin my ground clearance. Hopefully an X pipe, or at least an crossover pipe.

While it's on the lift i'll take lots of pics before, during, and after install.

:lala:

 

Cool, keep us posted. As far as ground clearance goes, with true duals it's already ruined...

 

if anyone else says "you'll make more power because you'll have more back pressure" i'm gunna cram a hooker long tube straight up their poop-shoot. LESS back pressure makes MORE power.....only at the expense of LESS LOW RPM TORQUE. put that in your crack pipe and snort it

 

I'm with Fast3rdGen on that one. I just didn't mention it earlier so we didn't get into a flame war on this topic again like so many times, but oh well, too late now.

 

Sick of H Pipes X Pipes and Y Pipes?
Get the O pipe with 100% backpressure.
Stop them all dead in their tracks!
*NEW* "U" pipe for stock motors and manifolds!

 

hahahahah

 

I definately gotta get one of those. the back pressure will really boost my torque LMAO!!!!:hail: :lala:

 

Question what size true duals are you going with? I hope with something over 2 1/2" because if not then you are wasting money and ground clearence. A single 3" will out flow a dual 2 1/2". Granted you might make a little more power up to with the duals but how often are you going to drive it on the street compared to the track? If its going more street then track i would find a good flowing single 3" because torque is your friend on the street. More track then street then go the duals because top end power is your friend on track.

 

I'm going with 3" duals with H pipe and DynoMax WLK-24222 Bullet, 3 in. center inlet/outlet, muffler ... I am not building a Track car nor do I want 450 hp! Simply put I'm building my dream street cruiser that will sound the way I want and kick *** on a few street races when challenged.

I had a BB Mopar with 3" exhaust once loved the sound. I know it will sound diff on the IROC but i'm sure it'll sound great.

I doubt i'll lose enuff torque to worry about spinning my tires when I want.

Thanx for the replies. I wan't trying to be snippy.

 

Hurray the headers are going in SLOWLY! Last night we took off the stock iron. Then proceded to hacksaw thru the old pipe, to remove the exhaust system. We ran into a snag, not enuff room to hacksaw all the way thru . Today we're breaking out the saws all. I'm going to take pictures during the install to document fitment and ease/difficulty of install, will post em as soon as possible. then i';m headed to an exhaust shop! for my 3" TRUE DUAL exhaust. I'll take pictures of it on the rack, and on the ground, hopefully to show ground clearance. Well that's my update, stay tuned for more details.

oh ya can't wait till my O pipe comes in hahaha

 

" = inches
' = feet

 

Yes 3" pipe diameter i didn't put 3'


Oh i see it now in the subject

 

Bzzzt.. Wrong answer. If you have dual 2 1/4 they have slightly more space than a single 3 inside, but not enough to make a difference. With 2 1/2 and up there is enough to make a difference, plus if you have an x or h pipe your scaenging is better than a single exhaust.

Here is some of the math that was done by five7kid.

Flow area of 2x2.25" OD vs. single 3" od (assuming 3/32" wall thickness for both):

2.25" - 3/32" for walls = 3.652 square inches. Times 2 = 7.304 square inches.

3.00" - 3/32" for walls = 6.634 square inches.

Difference = 0.670 square inches (2-1/4" duals greater than 3")

If wall thickness is more, 2.25" flow area difference over 3" is slightly less (.6 square inches for 1/8" total wall).

Ben

 

Inside Diameter(I.D.) = Outside Diameter - (Wall Thickness x 2)

Inside Area = (1/2 I.D.)(1/2 I.D.)(pi)

so using your imaginary 3/32" pipe thickness, we get the following:

2.25" Duals
-----------
Inside Diameter
2.25 - (3/32 x 2) = ID
2.25 - (0.09375 x 2) = ID
2.25 - 0.1875 = ID
2.0625" = ID

Area
(1.03125 x 1.03125 x 3.1416) = Inside Area
3.34 in sq = Inside Area
but double that cuz they're duals so,...

6.68 in sq = Inside Area of 2.25" duals

2.5" Duals
----------
Inside Area = 8.40 in sq

3.0" Single
----------
Inside Area = 6.21 in sq

3.5" Single
-----------
Inside Area = 8.62 in sq

So the 2.5" duals have 0.47 in sq(or 7.5%) more inside area than the 3" single, and the 2.5" duals up that to 2.19 in sq(35 %). The 3.5" single just edges past 2.5" duals in inside area(the 2.5% gain is insignificant), but installs without compromising ground clearance, something you might consider if you plan to lower your car.

 

Pipe wall thickness is expressed as a gauge,

Gauge Wall Thickness

BWG-- Inches
20--- 0.035
18--- 0.049
16--- 0.065
14--- 0.083
12--- 0.109
11--- 0.120
10--- 0.134
9 ---- 0.148
8 ---- 0.165
7 ---- 0.180
6 ---- 0.203
5 ---- 0.220
4 ---- 0.238
3 ---- 0.259

14 ga is most commonly used for exhaust pipe, however some cheap sets can be found with 16 ga pipe.

 

Well things are not going well! It seems i may have to pull the motor or at least lift it a little to get these things in. I'm not sure if they will even clear the A arm. So now the [roject is on hold for a few days

 

I was told that it said in the papers that came with them that you would have to lift the motor a few inches to put them in.

Ben

 

just for your reference, dual 3" is way too big for your application. you will lose so much torque it wont even be funny. dual 2 1/2 is fine. i have friends in the 12's on dual 2 1/2. even majorly built 350's dont need dual 3" most of the time.

 

Ya i figured i try it without lifting first oh well
Maybe i'll just use this as an excuse to yank her out an refresh the bottom end

And maybe i'll go 2 1/2" instead

 

Ok drivers side went in after lifting the motor and removing the winshield wiper motor

Problem how do you get a torque wrench on the bolts? and how much torque?

 

you just get whatever you can in there and get em as tight as you can (respectively, dont overtighten em) i dont know if you will be able to get normal exhaust bolts on, i had to use allen bolts to get them past the primaries.

 

Ok As stated earlier the drivers side is in but not torqued down.

The second primary tube is touching the K member. I think a new motor mount will cure this...I hope It only needs 1/16" to clear.

The steering shaft clears easily as do the brake lines. so far only the k member is touching everything else clears by a mile!

I'll be taking pictures today, will wait till project is complete and then I'll post pics.

Oh and when lifting the motor had to remove pass side ex manifold to lift high enuff. More than a few inches!