Ive read all the threads and am a little confused. Im trying to make a 3" exhaust starting from the I-pipe.

Do I have to call a company and ask about selling their 2 or 3 piece i-pipe separate from the kit?

Do these pieces need to be welded together?

Is there a place to get a complete 3" i-pipe

if you contact walker/dynomax they offer a 2 peice 3in mandrel bent I pipe I got it up here in canada from Napa and my shop rate cost me about 170$ for it if I remember correctly fits perfectly but because its a bigger pipe it does hang a little lower than the factory 2 1/2 in baby pipe that was there before if you go

Thanks. So will I just have to get the extension for the cat?

that pipe will mount right up to your factory catalitic convertor pipe at the clamp.

also I apoligise for my oh my god never ending run on sentence....I need to remember to prouf read before I hit reply!

Summit sells the intermediate pipe by itself...same with the factory tail pipes.

I want 3" intermediate though and I couldn,t find one. I have an 84 H.O.

No worries, thanks.

Can either of you two guys help me with a link on which ones I should use? I want to make sure its the right ones. Thanks

Sorry, just went and looked....looks like all I see is 2.5" ones. I swore I saw one that was 3" when I was looking...but it must have been a 2.5" one and I assumed it was 3".

you're best bet is to go to a napa yourself and go trough the catalog that's how I found it they do not have a litsting online for it

The 3" intermediate pipe used to be WLK-44063, but I just checked Summit and it is unavailable.

Well, thanks for looking. Ill go to napa like hiemarch suggested. They're ***holes by me, but what ever, I want that pipe.

Just a heads up: The HO has one of the best Y-pipe/intermediate pipes available on our cars. Check post #7 of the following link for a side-by-side comparison. Furthermore, the OE intermediate pipe is 2.75--the darned thing was larger than the after market piece I' swapped in when I had the old LG4. The stock set-up, along with a high-flow cat, is really quite nice.

https://www.thirdgen.org/forums/exha...-question.html

JamesC

If you walk into a parts store and you ask for a 3" intermediate pipe, the guy behind the counter isn't going to know what you're talking about. Asking to see the book probably isn't going to get you very far either. Assuming they even have a book, they probably won't know how to use it. But, this is the information age, you can find it online if you know where to look.

Forget searching on Summit, unless you already know what you're after they're only marginally more helpful then the clueless counter-jockey. If you go to www.walkerexhaust.com you can go to the catalog and see what they offer for stock replacement exhaust, and the part numbers. You can go to Dynomax.com and see what they offer as far as cat-back exhausts, and their part numbers. Also you can go to Flowmastermufflers.com and do the same. Then take those part numbers to Summit's website and search for the systems that fit your car. When you pull them up on the website there's a link that says "instructions". When you look through the instructions, they will give the part numbers included in the kit. Then you can search those part numbers on Summit's site and see if they're available separate and the price.

There are a few things to keep in mind.
First, after about 1985 the exhaust systems changed. Your 84 H.O. has a 4 bolt connection at the cat, later cars have a 2 bolt ball flange. So unless you change the flange, a later 3" I-pipe isn't going to bolt up. So you really need a pipe intended for a 1984 HO.
Second, the stock setup is a 2.75" intermediate pipe that necks down to 2.5" where it enters the muffler. A standard Walker replacement is mandrel bent, and at most a half inch smaller at it's smallest point. Any muffler that's sold as a bolt on replacement is going to have that 2.5" inlet. So if you get an I-pipe for a cat-back, and a muffler that's supposed to fit your car, they might not match up, unless the catback necks down the same way.

Also JamesC makes a really good point... The stock HO exhaust is damn close to any aftermarket 3" system, so there isn't a lot to gain. Several aftermarket systems, like Dynomax's 17494 (which fits your car) have a pipe that's not much better (if at all) then stock. A true 3" system is going to be hard to find, and probably won't fit your current muffler, or the few crossflow mufflers that are designed to fit your car. You'd be further ahead to just buy a cat-back exhaust with everything you need that matches.

However, if you still want to piece it together... Flowmaster, if they make a 4-bolt cat adapter, is probably your best bet if you really want a true 3" in/out intermediate pipe. They make two different systems (single tail pipe, or dual tail pipe), with different adapters to fit different cats, so their I-pipes are 3 piece systems. Last time I priced them out it was cheaper to buy the 3 piece Flowmaster, then the 2 piece Dynomax, and I can't say that I've ever seen a 2 piece Dynomax that fits the 4 bolt cat. The 2 piece Dynomax I-pipe was a leftover from a system they discontinued 20 years ago, so it's not a stretch that they've discontinued the pipe altogether.

Should you wish a high-flow direct-replacement cat for your 84, check Summit for CTO-4116. Following is an old pic:

https://www.thirdgen.org/forums/atta...y-pipe-cat.jpg

JamesC

Sorry, I should have explained my plans; I had a thread where people helped me decide the best way for me to go. I want the stock setup but make it 3" all around and get rid of the cat. Later, ill buy headers and y-pipe to match

Ive read about the 2 and 3 piece intermediate pipes but do they have to be clamped or welded together?

They are clamped together. By the time you get the parts pieced together you could buy a complete catback. I bought a Hooker Aerochamber with the 2 1/2" factory tailpipes a few weeks ago. Hoping to sell the Hooker tips and tailpipes for 50 bucks or so to recoup my costs of the tailpipes. It looks stock but oooooh, it doesn't sound stock.

http://www.youtube.com/watch?v=OsZ2h...layer_embedded

The problem is that most people don't differentiate much between a stock HO setup (2.75" pipe with 2.5" inlet muffler) and an aftermarket true 3" pipe with 3" inlet muffler. You can't really mix and match without adapters, or very careful planning. That's just one of the reasons to buy a cat-back exhaust that includes what you want. The other good reason is the cost, as mentioned earlier you'll save money buying the kit.

Generally speaking, every cat-back that Dynomax sells uses a copy of the stock I-pipe, right down to the size of the inlet at the muffler. To get a 3" Dynomax I-pipe you have to find the part from a kit they discontinued years ago.

Flowmaster's I-pipes are multiple pieces. You can clamp or weld them, or clamp them in position then have them welded up and remove the clamps. If you want a one piece I-pipe, Dynomax's stock replacement is about the only option out there.

Most other companies don't sell I-pipes separately. But usually the cat-back price is about the same as buying an I-pipe and a muffler, so it's like getting the tail pipes and clamps, etc for free. Also with a kit you know it's all going to fit together and fit the car. If you dump the 4-bolt cat you can probably get away with using any cat-back for HO cars. Most of the later TPI cars have the same larger exhaust, just with a different cat flange.

I just dont like the 2.75" pipe with the 2.5" muffler; I wanted something that doesn't change in size.

If it ends up being to much then there is a walker system ive been looking at from rockauto.com part #17494. With the mail in rebate its only 200, but my concern is what happened to jamesC where his was smaller.

I dont really have a preference to a one piece or 2-3 piece i-pipe. I have a friend whose dad is a good welder and will do it for me for cheap.

Walker and Dynomax are the same company, Dynomax is just the "performance" side of the business. Check the instructions for their kit's and take note of the clamp sizes. All of their current kits use an I-pipe that necks down to 2.5" at the muffler. It's not a big deal, the performance difference probably isn't going to be measurable, but if you want a true 3" system, Walker/Dynomax doesn't make one. What they did make was a 3" I-pipe for one of the older kits, but Summit doesn't find the part numbers anymore.
WLK-44063 & WLK-43248 are the two part numbers for a single cat 3" I-pipe. Funny because the pics are still on Summit's server. Just leave off the WLK prefix and you have the part number most places use. Rock Auto shows they're still available. Walker Exhaust is carried by most auto parts chains, so places like Napa and other local stores might be able to order them.

Nice, thanks. So what, if any, problems would occur with this I-pipe? I wanted to buy a Hooker Aerochamber muffler, to go with, so would I most likely need an adapter for the inlet?

I just ordered and received the Walker 3" intermediate pipe for my 1988 GTA so it is definitely available from Summit. I was using it to replace the botched-up I pipe for my SLP 2-on-the-left cat back system and it is a perfect fit.

http://www.summitracing.com/parts/WLK-44063/

Glad to hear that. However, when I click the link it says its not available.

Which I-pipe? The one piece Walker I-pipes all neck to 2.5" so unless you use a 2.5" inlet muffler, you'd either have to expand the pipe to 3", or use adapters. The two piece would fit the 3" inlet muffler, but the cat-converter end is wrong for your existing catalytic converter. It's just a ball flange, so again you'd have to find a way to adapt it over.

If you want to use a Hooker Aerochamber muffler, why not just get the Hooker catback designed for your car? You'll have $150 invested in a Walker/Dynomax I-pipe, and another $100 in the muffler, Hooker's 16822 exhaust http://www.summitracing.com/parts/HOK-16822HKR/ is $340 and actually bolts up to your car, everything will fit, and includes tail pipes, tips, clamps, etc. If you don't like the tips, sell them and use something else.

Did you miss where it says N/A Not Available under price?

I want to get rid of the cat, so wont I just need a 3" pipe(I forgot what its called) to replace the cat?

I also wanted the 3" outlet for the muffler and that system appears to have the 2.5" outlet