2 inch exhaust with 300+ hp 5.7

[Anubis]

Hi Everyone, posting this question here as well as the tahoeyukon forum.

Is anyone running 300+ hp through 2 inch down pipes?


SO should I ship it back? It seems there are few other bolt on solutions.

Good call on shipping it back. I run a 96' LT1 Corvette engine in my Z71 with about 350 hp and a full length 2.5" dual exhaust system. It has always sounded like crap and it has a tendency to resonate and rap like a glass pack regardless of what mufflers I put on it. I plan to go with a 3" exhaust system all the way back which will be needed for the soon to be boosted LS anyway.
Go 3" now if you can. It will look better AND sound better not to mention flow.

 

[YukonKyle]

The 2500 trucks had bigger head pipes and bigger cats stock. They're about 2.5" at the manifold, but flare up to 3" leading into the cat and back down to 2.75" post cat.

Any chance you have a part number for those? I looked at Rockauto and there a re a bunch by Walker and another made by Borsal, but no pipe sizes are listed. should I assume they are all 2.5?

 

[YukonKyle]

Any chance you have a part number for those? I looked at Rockauto and there a re a bunch by Walker and another made by Borsal, but no pipe sizes are listed. should I assume they are all 2.5?

Just called Walker for the K2500 cat system part 50410. they are 2" WTF?

 

[Supercharged111]

And the junkyards won't sell you any. Check Craigslist for a truck being parted out? Stock will still be an upgrade. Are you opposed to a full custom exhaust with aftermarket cats and 4 O2 bungs?

 

[YukonKyle]

Ok, just realised I need to be looking at K3500 trucks. Just need to check the front (Walker 50454) and back (Walker 50316) parts will fit under my stubby 2 door Yukon.... if they do I'm good, but the cost is getting closer to a custom exhaust.

Supercharged111, I will check the U-pulls if they do fit. Thanks

 

[Supercharged111]

So there was a light and heavy 2500, it could be that the 2" 2500 pipe you found was a light duty piece.

 

[b454rat]

Summit and Jegs dont carry the bigger pipes, even when punched in the numbers for a 1 ton. Some parts stores can get it, but I priced it and was like 6-700 bucks....Also should be any 8 lug 3/4 ton. I had a 99 CCSB with a 5.7 and had the bigger pipes.

 

[L31MaxExpress]

Summit and Jegs dont carry the bigger pipes, even when punched in the numbers for a 1 ton. Some parts stores can get it, but I priced it and was like 6-700 bucks....Also should be any 8 lug 3/4 ton. I had a 99 CCSB with a 5.7 and had the bigger pipes.

The Express vans have the largest exhaust. I used the front exhaust piping from an 8.1 Van when I put an 8.1 in my Tahoe. My 350 van had the same 3" pipes. They are 3" not the odd sized 2.75" the 8 lug trucks used.

 

[Supercharged111]

The Express vans have the largest exhaust. I used the front exhaust piping from an 8.1 Van when I put an 8.1 in my Tahoe. My 350 van had the same 3" pipes. They are 3" not the odd sized 2.75" the 8 lug trucks used.

The 2.75 is post cat, pre cat is 3" except for the very first part by the manifold flange.

 

[YukonKyle]

The 2.75 is post cat, pre cat is 3" except for the very first part by the manifold flange.

So that leads to another question, what diameter is the 5.7 K1500 exhaust manifold? Are they also bigger on the K3500s and Express vans?