Okay, I have two quick questions, one of which is a stupid one...

First, when they say 3 inch, is that outside diameter?

Second, does anyone know where I can get a intermediate pipe, the one that goes from the cat to the muffler?

thanks!

 

3" would mean the ID or inside diameter. Dynomax is the only one that I know of that makes an I pipe for our cars. It is 3". I am waiting to hear back from a memebr that ordered one for his car. I need to replace mine because I damaged the one on my hooker cat back.

 

I need one badly, mine has a hole right where it turns to go into the muffler. I patched it up once, but it is now burning/rusting through again.

If you have any information on where to order one, or if you hear back from that member that ordered a dynomax one, please let me know.

Thanks!!

 

I think this is him.
https://www.thirdgen.org/techbb2/sho...hreadid=217487

 

If only that were true...

Pipe is quoted as OD size. Connections (such as muffler inlet) are ID.

So, in order to calculate flow area you have to subract the wall thickness from the diameter.

 

Thanks for the correction. You learn something new every day. Water main pipe on the other hand are pretty consistant with ID's so I figured exhaust pipes would be the same. Learned that during one of my co-op stints. I have also seen things in Jegs advertised as 3" ID so I just figured as such. Thanks for keeping me straight.

 

I have Dynomax I-pipe and over axle they are 3" OD and they are grat aluminzed pipes but in my case the I-pipe had to be extended but thats cause i used a 3" universal cat and not a directfit cat.Here are #'s i used Prices are summit racing but you can get them at advanced auto for cheaper and no shipping!!

Dynomax 3” Intermediate Pipe WLK-44063 82.99
Dynomax 3” over Axle Pipe WLK-43248 48.99

 

So there are 2 pieces... think I could get away with just buying the over the axle pipe? The hole I have is right where the pipe turns and goes into the muffler, there are no other holes, could I just cut my existing one, and attach the over the axle pipe?

I will take a picture tomorrow, since I will be under there. but can anyone tell from my description?

 

from what you are saying probebly a good shop should be able to repair it for 40$ cut the pipe off the muffler and a little after the hole and bend a new pice and weld it on. have you trided this?

 

No I haven't tried that, as I hate going to any shops... but I actually did think of that, I think I should call around and see who gives free estimates, then have them look at it, might be worth it, think I need a new cat too, I'm getting some weird egg-ish smells lately, and I've been running rich for a while.

 

Went to the shop... they looked at it, and told me they couldn't weld it. They also found 2 more holes in it. They told me they could put a new 3" pipe in for 170 plus tax... is that a good price?

 

wow 170! how big is the pipe? and is it maderal bent?

 

Well if it is mandrel bent then you may have to bite the bullit and pay for it. This is one of those lose lose situations. However, you could always save a bit more and get a whole new cat-back of your choice. That may be the better bargin.

 

I called around and found it cheaper... the way I figured it, it was gonna cost me 132 for the pipe, plus shipping and handling, so it would be worth it if I could get a new pipe and get it installed for less than 150.

I called all the local muffler shops, and got a quote, for preferably 3" all the way back. Highest was 175, lowest was 100, so I opted to go to the place that said 100... got there, the guy I talked to on the phone wasn't there, but he told someone else about the 100 buck quote, and I got it done.

The guy put the car on the lift, and looked at the pipe, saw the same 3 holes, and noticed it was a 2 1/2 pipe, and said he didn't think he could fit 3", so he requoted me for 75 with 2 1/2 inch... then I insisted on 3" and he said he'd try and make it fit... turns out that it fit fine.

So 100 bux for the intermediate pipe, from cat to muffler. I figure the 3" will flow better than the 2 1/2, even tho it had a bit of a pinch where it had to go over the axle, not that bad tho.

Now just for some headers and a new cat (or hollowed out one, until smog time comes) and I will be completely set. My muffler is pretty much new (Flowmaster 50 series I believe), and my I-Pipe is new and bigger than before.

If anyone in the bay area needs muffler work done, go to Down Town Mufflers in Hayward, I highly reccomend them after what they did for me today!