Exhaust for 1998 L29

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EKOBS

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Here's the 454 thread; have a look around and see what you think.
Vortec 454 Thread
Personally, I'm putting JBA shorties on my truck (got them for practically free!) for ease of installation. You might have to fight with the long tubes a little in order to get them to fit, especially since your truck is a 4x4
Thanks for your response and that tip to the excellent Vortec thread. By the way I should have been more explicit in my description, my truck is actually a rear drive only version.
 

Supercharged111

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The Burns Merge collectors are impressive but on a stock engine they might not make much difference, But every little bit helps!

If there is a Tri-Y header I always recommend that. Any engine under 8000 RPM will see gains with that type over a 4 into 1 header.

180 degree headers are even better but good luck getting them to fit!

I recommend a proper Y or at least an X pipe. The gains can be dramatic.

For this I would do dual 2.5" into a single 3" Y pipe

https://www.summitracing.com/parts/flo-y250300s

with a WLK-17769 muffler

https://www.summitracing.com/parts/wlk-17769

and the biggest glass-pack after as a resonator.

This tail pipe kit


That would be optimum for 300 to 400 hp.

Single 3" for a big block? You sure about that? I used a 4" Diamondeye tailpipe. It comes in 2 pieces you weld together and weld on your own hangers too.
 

Frank Enstein

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Yes. For 300 to 400 horsepower. Above that go bigger. Flowmaster has some good info on this. Walker/Dynomax too.
 

Piratehunter

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Here's the 454 thread; have a look around and see what you think.
Vortec 454 Thread
Personally, I'm putting JBA shorties on my truck (got them for practically free!) for ease of installation. You might have to fight with the long tubes a little in order to get them to fit, especially since your truck is a 4x4
where did you find them at, looking for the same, out of stock everywhere.. thanks
 

yevgenievich

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where did you find them at, looking for the same, out of stock everywhere.. thanks
Summit has jba shorties either in stock or drop ship. I have a set that I am not sure if will be using as changing plans
 
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Piratehunter

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Summit has jba shorties either in stock or drop ship. I have a set that I am not sure if will be using as changing plans
Thanks I found them…was searching with the wrong part number….I wonder why they charge more for the non-air headers than the the Air fitted headers, almost $200
 

TexasAggie

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I was getting ready to start this exact thread for my '99 K2500 Suburban with 454. I'm pulling the trigger on a set of JBA long tubes (wish Thorley Tri-Ys were still available). Stock engine, other than a Blackbear tune (will get re-tuned after exhaust). I am thinking of going with a dual 3" setup through new high flow cats, x pipe, and twin mufflers of some type. Looking for a nice deep sound that is loud, but not obnoxiously so.

One thing I was wondering about is the collectors on these headers - they are 3" at the end of the header, but the piece that bolts on is 2.5". Do I need to find a set that is 3" in order to maximize the 3" dual exhaust?

Any thoughts on this setup? Likes/dislikes?
 

Erik the Awful

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For a big block, I think your plan of running a 3" exhaust all the way out is fairly spot-on. If you're looking at the JBA's 6822S headers, it looks like the 2.5" is just a reducer that comes with it - I'd call and ask. If so, leave it off and build your 3" exhaust from there.
 

TexasAggie

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Any thoughts on specific cats or mufflers?

I think you're right about the reducer... I'll just have the shop make some new ones to bolt up with 3" pipe.
 
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